330M Komatzu PDF

DG728
330M A10190 Thru

330M A10211
Unsafe use of this machine may cause serious injury or death.
Operators and maintenance personnel must read and understand
this manual before operating or maintaining this machine.
This manual should be kept in or near the machine for reference,
and periodically reviewed by all personnel who will come into
contact with it.
This material is proprietary to Komatsu Mining Systems, Inc. and is not

to be reproduced, used, or disclosed except in accordance with written
authorization from Komatsu Mining Systems, Inc.
It is the policy of the Company to improve products whenever it is possibl
and practical to do so. The Company reserves the right to make changes
or add improvements at any time without incurring any obligation to install
such changes on products sold previously.
Because of continuous research and development, periodic revisions
may be made to this publication. Customers should contact their local
distributor for information on the latest revision.
CALIFORNI
Proposition 65 Warning
Diesel engine exhaust and some of its constituents are known to
the State of California to cause cancer, birth defects and othe
reproductive harm.
FOREWORD
This Manual is written for use by the service technician and is designed to help the technician become
fully knowledgeable of the truck and all its systems in order to keep it running and in production. All
maintenance personnel should read and understand the materials in this manual before performing
maintenance and/or operational checks on the truck. All safety notices, warnings and cautions should
be understood and followed when accomplishing repairs on the truck.
The first section covers component descriptions, truck specifications and safe work practices, as
well as other general information. The major portion of the manual pertains to disassembly, service
and reassembly. Each major serviceable area is dealt with individually. For example: The disassem-
bly, service and reassembly of the radiator group is discussed as a unit. The same is true of the
engine and engine accessories, and so on through the entire mechanical detail of the truck.
Disassembly should be carried only as far as necessary to accomplish needed repairs.
The illustrations used in this manual are, at times, typical of the component shown and may not
necessarily depict a specific model.
This manual shows dimensioning of U.S. standard and metric (SI) units throughout and all references
to "Right", "Left", "Front", or "Rear" are made with respect to the operator’s normal seated position,
unless specifically stated otherwise.
Standard torque requirements are shown in torque charts in the general information section and
individual torques are provided in the text in bold face type, such as 100 ft.lbs. (135 N.m) torque.
All torque specifications have ±10% tolerance unless otherwise specified.
A Product Identification plate is normally located on the truck frame upright in front of the left side
front wheel and designates the Truck Model Number, Product Identification Number (vehicle serial
number), and Maximum G.V.W. (Gross Vehicle Weight) rating.
®
The HAULPAK Model designation consists of three numbers and one letter (i.e. 330M). The three
numbers represent the basic truck model. The letter "M" designates a Mechanical drive and the letter
"E" designates an Electrical propulsion system.
The Product Identification Number (vehicle serial number) contains information which will identify
the original manufacturing bill of material for this unit. This complete number will be necessary for
proper ordering of many service parts and/or warranty consideration.
The Gross Vehicle Weight (GVW) is what determines the load on the drive train, frame, tires, and
other components. The vehicle design and application guidelines are sensitive to the total maximum
Gross Vehicle Weight (GVW) and this means the total weight: the Empty Vehicle Weight + the
fuel & lubricants + the payload.
To determine allowable payload:
Service all lubricants for proper level and fill fuel tank of empty truck (which includes all accessories,
body liners, tailgates, etc.) and then weigh truck.
Record this value and subtract from the GVW rating. The result is the allowable payload.
NOTE: Accumulations of mud, frozen material, etc. become a part of the GVW and reduces allowable
payload. To maximize payload and to keep from exceeding the GVW rating, these accumulations
should be removed as often as practical.
Exceeding the allowable payload will reduce expected life of truck components.
A00019 Introduction A-1

This “ALERT” symbol is used with the signal words,
“CAUTION”, “DANGER”, and “WARNING” in this man-
ual to alert the reader to hazards arising from
improper operating and maintenance practices.
“DANGER” identifies a specific potential hazard

WHICH WILL RESULT
in either INJURY OR DEATH
if proper precautions are not taken.
“WARNING” identifies a specific potential hazard

WHICH MAY RESULT
in either INJURY OR DEATH
if proper precautions are not taken.
“CAUTION” is used for general reminders

of proper safety practices
OR
to direct the reader’s attention to avoid unsafe
or improper practices which may result
in damage to the equipment.
A-2 Introduction A00019

TABLE OF CONTENTS
SUBJECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SECTION
GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A
STRUCTURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B
ENGINE, FUEL, COOLING AND AIR CLEANER . . . . . . . . . . . . . . . . . . . . . . . . . C
ELECTRIC SYSTEM (24 VDC. NON-PROPULSION) . . . . . . . . . . . . . . . . . . . . . . D
TRANSMISSION AND TORQUE CONVERTER . . . . . . . . . . . . . . . . . . . . . . . . . F
DRIVE AXLE, SPINDLES AND WHEELS . . . . . . . . . . . . . . . . . . . . . . . . . . . G
SUSPENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H
BRAKE CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J
AIR SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K
HYDRAULIC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L
OPTIONS AND SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M
OPERATOR’S CAB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N
LUBRICATION AND SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P
ALPHABETICAL INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Q
SYSTEM SCHEMATICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . R
A00019 Introduction A-3

KOMATSU 330M HAULPAK TRUCK
A-4 Introduction A00019

SECTION A
GENERAL INFORMATION
INDEX
TRUCK COMPONENT DESCRIPTION & SPECIFICATIONS . . . . . . . . . . . . . . . . A2-1
GENERAL SAFETY AND TRUCK OPERATION . . . . . . . . . . . . . . . . . . . . . . . A3-1
WARNINGS AND CAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A4-1
CHARTS AND TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A5-1
STANDARD MAINTENANCE VALUES . . . . . . . . . . . . . . . . . . . . . . . . . . . A6-1
A01004 Index A1-1

NOTES
A1-2 Index A01004

MAJOR COMPONENTS AND SPECIFICATIONS
ENGINE POWER STEERING

The 330M Truck is powered by a Komatsu diesel The 330M is equipped with full hydraulic power steer-
engine. ing. The system includes an electric motor driven
pump which automatically provides emergency power
if the steering pump hydraulic flow is reduced below
an established minimum.
TRANSMISSION
The TORQFLOW transmission consists of a 3-ele- BRAKE SYSTEM
ment, single-stage, two-phase torque converter and a
Depressing the brake pedal actuates front and rear
planetary gear, multiple disc clutch transmission which
air-over-hydraulic service brakes. The front service
is hydraulically actuated and force-lubricated for opti-
brakes are caliper disc type. The rear service brakes
mum heat dissipation.
are oil-cooled, multiple-disc brakes (acts also as re-
The TORQFLOW transmission is capable of seven (7)
tarder).
forward speeds and one (1) reverse gear. Automatic
shifting is controlled by electronic shift control with
automatic clutch modulation in all gears. A lockup
system consisting of a wet, double-disc clutch, is acti-
vated in F1–F7 gears for increased fuel savings.
RETARDER
The operator can manually apply the rear oil-cooled,
FINAL DRIVE ASSEMBLY multiple-disc retarder brakes by moving the retarder
contol lever which is mounted on the steering column.
The final drive consists of a plug-in differential with These brakes are automatically activated when the
planetary wheel drive. engine speed exceeds the rated revolutions of the shift
position.
OPERATOR’S CAB
The Operator’s Cab is spacious and comfortable and
includes wide windows all around for excellent visibil- SUSPENSION
ity. All pedals, controls and instruments are arranged
Hydro-pneumatic suspension cylinders are used at
for maximum efficiency and ease of operation. The
each wheel to reduce shock and provide riding comfort
electronic display/monitoring panel keeps the operator
for the operator and machine stability.
informed of the truck’s operating systems. Audible
alarms and lights warn the operator of system malfunc-
tions.
A02039 Major Components and Specifications A2-1

330M MAJOR COMPONENTS
A2-2 Major Components and Specifications A02039

SPECIFICATIONS
ENGINE SERVICE CAPACITIES
Komatsu . . . . . . . . . . . . . . . SA12V140Z-1 . . . . . . . . . . . . . . Liters . U.S. Gallons
Engine . . . . . . . . . . . 147 . . . . . . (39)
Number of Cylinders . . . . . . . . . . . . . . . 12 (Includes Lube Oil Filters)
Operating Cycle . . . . . . . . . . . . . . 4-Stroke Cooling System . . . . . . 256 . . . . . . (66)
Fuel Tank . . . . . . . . . . 1250 . . . . . (330)
Rated 783 kW (1050 SAE Brake HP) @ 2000 RPM Transmission . . . . . . . . 125 . . . . . . (33)
Flywheel . . 753 kW ( 1010 SAE HP) @ 2000 RPM And Torque Converter
Steering & Hoist System . . . 248 . . . . . (65.5)
Maximum torque 4631 N.m (3415 lb-ft) @ 1400 RPM Tank Only . . . . . . . . 145 . . . . . (38.3)
Brake Cooling System . . . 366 . . . . . (96.6)
Tank Only . . . . . . . . . 248 . . . . . (65.5)
TORQFLOW TRANSMISSION Final Drive Case . . . . . . . 250 . . . . . . (66)
Differential & both planetaries
Automatic Electronic Shift Control
. . . with Automatic Clutch Modulation In All Gears. HYDRAULIC SYSTEM
Lockup Clutch . . . . . . . . . Wet, Double-disc, The steering/hoisting and retarder cooling circuits are
. . . . . . . . . . . . . . Activated in F1–F7 gears. independent circuits. Load sensing steering system
controls the flow to the steering circuit in accordance
Torque Converter . . . . 3-Element, Single-stage, with demand.
. . . . . . . . . . . . . . . . . . . . . Two-phase
Hydraulic Pumps . . . . . 2-Separate Gear Pumps
Transmission . Planetary Gear, Multiple Disc Clutch,
Steering/Hoist Functions
. . . . . Hydraulically Actuated, Force-lubricated Flow rated at . . . 636 l/min. (168 U.S. gal/min.)
Speeds . . . . . . . . . . . 7 Forward, 1 Reverse Retarder Cooling
Flow rated at . . 1001 l/min. (264 U.S. gal/min.)
Max Travel Speed . . . . . 61.9 Km/h (38.5 MPH)
Hoist Control Valve . . . . . . . . . . . Spool Type
Positions . . . . . Raise, Hold, Float, and Lower
FINAL DRIVE ASSEMBLY Hydraulic Cylinders
Final Drive . . . . . . . . . . . Plug-in Differential Hoisting . . . . . . . 2-Stage Telescoping Piston
. . . . . . . . . . . . . with Planetary Wheel Drive Steering . . . . . . . . . . . Double Acting Piston
2
Reduction Ratios: Relief Valve Setting . . . . 210 kg/cm (3,000 psi)
Bevel Set . . . . . . . . . . . . . . . . . . 3.47:1 SERVICE BRAKES
Planetary Final Drive . . . . . . . . . . . . 6.50:1
Total Reduction . . . . . . . . . . . . . . 22.54:1 Actuation: . . . . . . . . . . . . Air-Over-Hydraulic
Front . . . . . . . . . . . . . Caliper Disc Brakes
Rear . . . . . . . . . . . Oil-Cooled, Multiple-Disc
ELECTRIC SYSTEM . . . Act as both Service and Retarder Brakes
Batteries . . . . . . . . . . 4 x 12V / 200 Amp Hr. Retarder Brakes:
. . . . . . . . . . . . . 1450 Cold Cranking Amps Normally Applied . . . . Manually By Operator.
Alternator . . . . . . . . 24 Volt, 75 Ampere Output Automatically Actuated . . . . . . . . . . . . .
when engine speed exceeds the rated revolu-
Lighting . . . . . . . . . . . . . . . . . . . 24 Volt tions of the shift position for the transmission.
Parking Brake: . . . Spring-loaded, Caliper Disc
Starter . . . . . . . . . . . . . . . . . One 24-Volt . . . . . . . . . . . . . Actuates On Drive Shaft
Emergency Brakes:
An emergency relay valve actuates the brakes
AIR SYSTEM automatically should air pressure in the air tank
3 drop below a pre-set value.
Compressor . . . . 0.85 m /min . . . . (30 cfm) Manual operation is also possible.
A02039 Major Components and Specifications A2-3

STEERING WEIGHT DISTRIBUTION
3 3
Min Turning Radius . . . . . . . . . . 9.9 m (32’ 6") Based on SAE 2:1 Heaped . . . . 60 m (78 yds )
(w/Komatsu Engine; and 27.00R49 Tires)
Automatic Emergency Steering . . . . . Standard
TIRES EMPTY . . . . . . . . Kilograms . . . Pounds

Front Axle . . . . . . . 33 145 . . . . 73,080
Rock Service (E-3) . . . . . . . . . . . . Tubeless
Rear Axle . . . . . . . 35 905 . . . . 79,170
Standard . . . . . . . . . . . . . 27.00R49XRBT Total . . . . . . . . . . 69 050 . . . 152,250
Rim Size . . . 50 cm X 124.4 cm (19.5 in. X 49 in.)
. . . . . . . . . . . . . . . . Separable Tire Rims LOADED (100 Ton PAYLOAD)
. . . . . . . . . . . . . Kilograms . . . Pounds
DUMP BODY CAPACITY (Standard) Front Axle . . . . . . . 54 080 . . . 119,280
3 3 Rear Axle . . . . . . 112 320 . . . 247,720
Struck . . . . . . . . . . . . . 38.6 m (50.5 yds )
Total * . . . . . . . . 166 400 . . . 367,000
3 3
Heaped @ 2:1 (SAE) . . . . . 60.1 m (78.7 yds )
* Not to Exceed 166 400 kg (367,000 lbs.).
Including Options, Fuel & Payload
OVERALL TRUCK DIMENSIONS

Loading Height . . . . . . . . . . . 4.29 m (14’ 1")
Minimum Clearance Height (Empty) 5.27 m (17’ 3")
Overall Length . . . . . . . . . . 10.47 m (34’ 4")
Maximum Width . . . . . . . . . . . 5.68 m (18’ 7")
OVERALL TRUCK DIMENSIONS

All dimensions shown are with 27.00-49 tires.
A2-4 Major Components and Specifications A02039

GENERAL SAFETY
This safety section also contains precautions for optional equipment and attachments.
Read and follow all safety precautions. Failure to do so may result

in serious injury or death.
SAFETY RULES
• ONLY trained and authorized personnel can operate and maintain the machine.
• Follow all safety rules, precautions and instructions when operating or performing maintenance on the machine.
• When working with another operator or a person on worksite traffic duty, be sure all personnel understand all
hand signals that are to be used.
SAFETY FEATURES
• Be sure all guards and covers are in their proper position. Have guards and covers repaired if damaged. (See
Walk-Around Check, Page 3-17 )
• Learn the proper use of safety features such as safety locks, safety pins, and seat belts, and use these safety
features properly.
• NEVER remove any safety features. ALWAYS keep them in good operating condition.
• Improper use of safety features could result in serious bodily injury or death.
CLOTHING AND PERSONAL PROTECTIVE ITEMS

• Avoid loose clothing, jewelry, and loose long hair. They can catch on controls or in moving parts and cause
serious injury or death. Also, do not wear oily clothes because they are
flammable.
• Wear a hard hat, safety glasses, safety shoes, mask or gloves when
operating or maintaining the machine. Always wear safety goggles, hard
hat and heavy gloves if your job involves scattering metal chips or minute
materials--this is so particularly when driving pins with a hammer and
when cleaning the air cleaner element with compressed air. Check also
that there is no one near the machine.
UNAUTHORIZED MODIFICATION
• Any modification made without authorization from Komatsu can create hazards.
• Before making a modification, consult your Komatsu distributor. Komatsu will not be responsible for any injury
or damage caused by any unauthorized modification.
A03011 4/98 General Safety and Operating Instructions A3-1

STANDING UP FROM THE SEAT
• To prevent any accident occurring if you should touch any control lever that is not locked, always carry out the
following before standing up from the operator’s seat.
• Place the gear shift lever at neutral and set the parking lever to the PARKING position.
• Lower the dump body, set the dump lever to the HOLD position, then apply the lock.
• Stop the engine. When leaving the machine, always lock everything. Always remember to take the key with you.
If the machine should suddenly move or move in an unexpected way, this may result in serious bodily injury or
death.
MOUNTING AND DISMOUNTING

• NEVER jump on or off the machine. NEVER get on or off a moving machine.
• When getting on or off the machine, face the machine and use the handhold and steps.
• Never hold any control levers when getting on or off the machine.
• Always maintain three-point contact with the handholds and steps to ensure that you support yourself.
• When bringing tools to the operator’s compartment, always pass them by hand or pull them up by rope.
• If there is any oil, grease, or mud on the handholds or steps, wipe it off immediately. Always keep these parts
clean. Repair any damage and tighten any loose bolts.
• Use the handrails and steps marked by arrows in the diagram below when getting on or off the machine.
A: For use when getting on or off the machine from the left door.
B: For use when getting on or off the machine from the engine hood or right door.
FIRE PREVENTION FOR FUEL AND OIL

Fuel, oil, and antifreeze can be ignited by a flame. Fuel is particularly FLAMMABLE and can be HAZARDOUS.
• Keep flame away from flammable fluids.
• Stop the engine and do not smoke when refueling.
• Tighten all fuel and oil tank caps securely.
• Refueling and oiling should be made in well ventilated areas.
• Keep oil and fuel in the determined place and do not allow unauthorized persons to enter.
A3-2 General Safety and Operating Instructions A03011 4/98

PRECAUTIONS WHEN HANDLING AT HIGH TEMPERATURES
• Immediately after operations, the engine cooling water, engine oil, differential and final drive case oil, and
hydraulic oil are at high temperature and are under pressure. If the cap is removed or the oil or water is drained
or the filters are replaced, there is danger of serious burns. Always wait for the temperature to go down, and carry
out the operation according to the specified procedure.
• To prevent hot water from spurting out:
1) Stop the engine.
2) Wait for the water temperature to go down.
3) Turn the cap slowly to release the pressure before removing the cap.
• To prevent hot oil from spurting out:
1) Stop the engine.
2) Wait for the oil temperature to go down.
3) Turn the cap slowly to release the pressure before removing the cap.
ASBESTOS DUST HAZARD PREVENTION

Asbestos dust can be HAZARDOUS to your health if it is inhaled.
If you handle materials containing asbestos fibers, follow these guidelines as given
below:
• NEVER use compressed air for cleaning.
• Use water for cleaning to keep down the dust.
• Operate the machine with the wind to your back, whenever possible.
• Use an approved respirator if necessary.
PREVENTION OF INJURY BY WORK EQUIPMENT

• Never enter or put your hand or arm or any other part of your body between movable parts such as the dump
body and chassis or cylinders. If the work equipment is operated, the clearance will change and this may lead
to serious bodily injury or death.
FIRE EXTINGUISHER AND FIRST AID KIT

• Be sure fire extinguishers have been provided and know how to use them.
• Provide a first aid kit at the storage point.

• Know what to do in the event of a fire.
• Be sure you know the phone numbers of persons you should contact in case of
an emergency.

PRECAUTIONS WHEN USING ROPS
• If ROPS is installed, the ROPS must never be removed when operating the machine.
• The ROPS is installed to protect the operator if the machine should roll over. If is designed not only to support
the load if the machine should roll over, but also to absorb the impact energy.
• The Komatsu ROPS fulfills all of the regulations and standards for all countries, but if it is rebuilt without
authorization or is damaged when the machine rolls over, the strength will drop and it will not be able to fulfill its
function properly. It can only display its performance if it is repaired or modified in the specified way.
• When modifying or repairing the ROPS, always contact your Komatsu distributor.
• Even if the ROPS is installed, it cannot show its full effect if the operator does not fasten the seat belt properly.
Always fasten the seat belt when operating.
PRECAUTIONS FOR ATTACHMENTS

• When installing and using an optional attachment, read the instruction manual for the attachment and the
information related to attachments in this manual.
• Do not use attachments that are not authorized by Komatsu or your Komatsu distributor. Use of unauthorized
attachments could create a safety problem and adversely affect the proper operation and useful life of the
machine.
• Any injuries, accidents, and product failures resulting from the use of unauthorized attachments will not be the
responsibility of Komatsu.

PRECAUTIONS DURING OPERATION
BEFORE STARTING ENGINE
SAFETY AT WORKSITE
• Before starting the engine, thoroughly check the area for any unusual conditions that could be dangerous.
• Examine the road surface in the jobsite and determine the best and safest method of operation.
• Choose an area where the ground is as horizontal and firm as possible before carrying out the operation.
• If you need to operate on a road, protect pedestrians and cars by designating a person for worksite traffic duty
or by installing fences around the worksite.
• Check the river bed condition, and depth and flow of water before crossing shallow parts of river. NEVER be in
water which is in excess of the permissible water depth.
• The operator must check personally the work position, roads to be used, and existence of obstacles before starting
operations.
• Always determine the travel roads in the worksite and maintain them so that it is always safe for the machines
to travel.
FIRE PREVENTION
• Thoroughly remove wood chips, leaves, paper and other flammable things accumulated in the engine compart-
ment. They could cause a fire.
• Check fuel, lubrication, and hydraulic systems for leaks. Have any leaks
repaired. Wipe up any excess oil, fuel or other flammable fluids.
• Be sure a fire extinguisher is present and working.
• Do not operate the machine near any flame.
IN OPERATOR’S CAB
• Do not leave tools or spare parts lying around in the operator’s compartment. They may damage or break the
control levers or switches. Always put them in the tool box on the right side of the machine.
• Keep the cab floor, controls, steps and handrails free of oil, grease, snow, and excess dirt.
• Check the seat belt, buckle and hardware for damage or wear. Replace any worn or damaged parts. Always use
seat belts when operating your machine.
VENTILATION FOR ENCLOSED AREAS

• If it is necessary to start the engine within an enclosed area, provide adequate ventilation.
Exhaust fumes from the engine can KILL.

KEEP MIRRORS, WINDOWS, AND LIGHTS CLEAN
• Remove any dirt from the surface of the windows or lights to ensure good visibility.
• Adjust the rear view mirror to a position where the operator can see best from the operator’s seat, and keep the
surface of the mirror clean. If any glass should break, replace it with a new part.
• Check that the machine is equipped with the head lamps and working lamps needed for the operating conditions.
Check that all the lamps light up properly.

OPERATING MACHINE
WHEN STARTING ENGINE

• Walk around your machine again just before mounting it, checking for people and objects that might be in the
way.
• NEVER start the engine if a warning tag has been attached to the control.
• When starting the engine, sound the horn as an alert.
• Start and operate the machine only while seated.
• Do not allow any person other than the operator in the operator’s compartment or any other place on the machine.
• For machines equipped with a back-up alarm buzzer, check that the alarm buzzer works properly.
CHECK WHEN TRAVELING IN REVERSE

Before operating the machine or work equipment, do as follows:
• Sound the horn to warn people in the area.
• Check that there is no one near the machine. Be particularly careful to check
behind the machine.
• If necessary, designate a person to check the safety. This is particularly
necessary when traveling in reverse.
• When operating in areas that may be hazardous or have poor visibility,
designate a person to direct worksite traffic.
• Do not allow any one to enter the line of travel of the machine. This rule must
be strictly observed even on machines equipped with a back-up alarm or rear view mirror.
TRAVELING
• When traveling on rough ground, travel at low speed. When changing direction, avoid turning suddenly.
• Lower the dump body and set the dump lever to the FLOAT position when traveling.
• If the engine should stop when the machine is traveling, the steering wheel will not work, and it will be dangerous
to drive the machine. Apply the brakes immediately and stop the machine.
TRAVELING ON SLOPES
• Traveling on slopes could result in the machine tipping over or slipping.
• Do not change direction on slopes. To ensure safety, go down to level ground before turning.
• Do not travel up and down on grass, fallen leaves, or wet steel plates. These materials may make the machine
slip on even the slightest slope. Take all possible steps to avoid traveling sideways, and always keep the travel
speed low.
• When traveling downhill, use the retarder brake to reduce speed. Do not turn the steering wheel suddenly. Do
not use the foot brake except in an emergency.
• If the engine should stop on a slope, apply the brakes fully and apply the parking brake, also, to stop the machine.

ENSURE GOOD VISIBILITY
• When working in dark places, install working lamps and head lamps, and set up lighting in the work area if
necessary.
• Stop operations if the visibility is poor, such as in mist, snow, or rain, and wait for the weather to improve to a
condition that allows the operation to be carried out safely.
OPERATE CAREFULLY ON SNOW

• When working on snowy or icy roads, there is danger that the machine may slip to the side on even the slightest
slope, so always travel slowly and avoid sudden starting, turning, or stopping.
• Be extremely careful when carrying out snow-clearing operations. The road shoulder and other objects are buried
in the snow and cannot be seen.
• When traveling on snow-covered roads, always install tire chains.
AVOID DAMAGE TO DUMP BODY

• When working in tunnels, on bridges, under electric cables, or when entering a parking place or any other place
where there are height limits, always drive extremely carefully and lower the dump body completely before driving
the machine.
DO NOT GO CLOSE TO HIGH-VOLTAGE CABLES

• Going close to high-voltage cables can cause electric shock. Always maintain the safe distance given below
between the machine and the electric cable.
Voltage Min. Safety Distance

6.6 kV 3m 10 ft
33.0 kV 4m 14 ft
66.0 kV 5m 17 ft
154.0 kV 8m 27 ft
275.0 kV 10 m 33 ft
• The following actions are effective in preventing accidents:

1) Wear shoes with rubber or leather soles.
2) Use a signalman to give warning if the machine approaches too close to the electric cable.
• If the work equipment should touch the electric cable, the operator should not leave the operator’s compartment.
• When carrying out operations near high voltage cables, do not let anyone come close to the machine.
• Check with the electricity company about the voltage of the cables before starting operations.

WHEN DUMPING
• Before starting the dumping operation, check that there is no person or object behind the machine.
• Stop the machine in the correct position, and check again that there is no person or object behind the machine.
Give the determined signal, then slowly operate the dump body. If necessary, use blocks for the wheels or position
a flagman.
• When carrying out dumping operations on slopes, the machine stability will become poor and there is danger
that it may tip over. Always carry out such operations extremely carefully.
• Do not travel with the dump body raised.
WORKING ON LOOSE GROUND

• Avoid operating your machine too close to the edge of cliffs, overhangs, and deep ditches. If these areas collapse,
your machine could fall or tip over and result in serious injury or death. Remember that the soil after heavy rain
or blasting is weakened in these areas.
• Earth laid on the ground and the soil near ditches are loose. They can collapse under the weight or vibration of
your machine.
• When operating in places where there is danger of falling rocks or danger of the machine turning over, always
install ROPS and a seat belt.
WHEN LOADING
• Check that the surrounding area is safe, stop the machine in the correct loading position, then load the body
uniformly.
• Do not leave the operator’s seat during the loading operation.
PARKING THE MACHINE

• Choose a horizontal road surface to park the machine. If the machine has to be parked on a slope, always put
blocks under all the wheels to prevent the machine from moving.
• When parking on public roads, provide fences and signs, such as flags or lights, on the machine to warn
pedestrians and other vehicles. Be sure that the machine, flags, or lights do not obstruct the traffic.
• Before leaving the machine, lower the dump body fully, set the parking lever to the PARKING position, stop the
engine, then lock everything. Always take the key with you.

BATTERY
BATTERY HAZARD PREVENTION

• Battery electrolyte contains sulfuric acid and can quickly burn the skin and eat holes in clothing. If you spill acid
on yourself, immediately flush the area with water.
• Battery acid could cause blindness if splashed into the eyes. If acid gets into the eyes, flush them immediately
with large quantities of water and see a doctor at once.
• If you accidentally drink acid, drink a large quantity of water or milk, beaten egg or vegetable oil. Call a doctor or
poison prevention center immediately.
• When working with batteries ALWAYS wear safety glasses or goggles.
• Batteries generate hydrogen gas. Hydrogen gas is very EXPLOSIVE, and is easily ignited with a small spark of
flame.
• Before working with batteries, stop the engine and turn the starting switch to the OFF position.
• Avoid short-circuiting the battery terminals through accidental contact with metallic objects, such as tools, across
the terminals.
• When removing or installing, check which is the positive (+) terminal and negative (-) terminal.
• Tighten the battery cap securely.
• Tighten the battery terminals securely. Loosened terminals can generate sparks and lead to an explosion.
STARTING WITH BOOSTER CABLES

• ALWAYS wear safety glasses or goggles when starting the machine with booster cables.
• When starting from another machine, do not allow the two machines to touch.
• Be sure to connect the positive (+) cable first when installing the booster cables. Disconnect the ground or negative
(-) cable first when removing them.
• If any tool touches between the positive (+) terminal and the chassis, it will cause sparks. This is dangerous, so
be sure to work carefully.
• Connect the batteries in parallel: positive to positive and negative to negative.
• When connecting the ground cable to the frame of the machine to be started, be sure to connect it as far as
possible from the battery.

TOWING
WHEN TOWING, FIX WIRE TO HOOK

• Towing in the wrong way may lead to serious personal injury or damage.
• When using another machine to tow this machine, use a wire rope with ample strength for the weight of this
machine.
• Never tow a machine on a slope.
• Do not use any towing rope that has kinks or is twisted.
• Do not stand astride the towing cable or wire rope.

• When connecting a machine that is to be towed, do not let any one come
between the towing machine and the machine that is being towed.
• Set the coupling of the machine being towed in a straight line with the towing
portion of the machine, and secure it in position.
(For towing method, see page 3-28.)

PRECAUTIONS FOR MAINTENANCE
BEFORE CARRYING OUT MAINTENANCE
WARNING TAG
• If others start the engine or operate the controls while you are performing service or lubrication, you could suffer
serious injury or death.
• ALWAYS attach the WARNING TAG to the control lever in the operator’s cab to alert others that you are working
on the machine. Attach additional warning tags around the machine, if necessary.
• These tags are available from your Komatsu distributor. (Part No. 09963-03000)
PROPER TOOLS
• Use only tools suited to the task. Using damaged, low quality, faulty, or makeshift tools
could cause personal injury.
PERIODIC REPLACEMENT OF CRITICAL PARTS

• Periodically replace parts used to insure safety or prevent accident. (See "PERIODIC REPLACEMENT OF
COMPONENT PARTS FOR SAFETY DEVICES", Section 4.)
• Replace these components periodically with new ones, regardless of whether or not they appear to be defective.
These components deteriorate over time.
• Replace or repair any such components if any defect is found, even though they have not reached the time
specified.
STOPPING THE ENGINE BEFORE SERVICE

• When carrying out inspection or maintenance, always stop the machine on firm flat ground, lower the dump body,
then stop the engine.
• If the engine must be run during service, such as when cleaning the radiator, always set the transmission lever
to the neutral position and the parking brake lever to the PARKING position. Always carry out the work with two
people. One person should sit on the operator’s seat so that he can stop the engine if necessary. NEVER move
any controls you do not need to operate.
• When servicing the machine, be careful not to touch any moving part or get your clothes caught.
• Put blocks under the wheels.
• When carrying out service with the dump body raised, always place the dump lever at the HOLD position, apply
the lock, and insert the safety pins securely.

DURING MAINTENANCE
PERSONNEL
• Only authorized personnel can service and repair the machine. Extra precaution should be used when grinding,
welding, and using a sledge-hammer.
ATTACHMENTS
• Place attachments that have been removed from the machine in a safe place so that they
do not fall. If they fall on you or others, serious injury could result.
WORK UNDER THE MACHINE

• Always lower all movable work equipment to the ground or to their lowest position before
performing service or repairs under the machine.
• Always block the tires of the machine securely.
• Never work under the machine if the machine is poorly supported.
KEEP THE MACHINE CLEAN
• Spilled oil or grease, or scattered tools or broken pieces are dangerous because
they may cause you to slip or trip.
Always keep your machine clean and tidy.
• If water gets into the electrical system, there is danger that the machine may not
move or may move unexpectedly.
Do not use water or steam to clean the sensors, connectors, or the inside of the
operator’s compartment.
RULES TO FOLLOW WHEN ADDING FUEL OR OIL

• Spilled fuel and oil may cause you to slip, so always wipe it up immediately.
• Always tighten the cap of the fuel and oil fillers securely.
• Never use fuel for washing any parts.
• Always add fuel and oil in a well-ventilated place.

RADIATOR WATER LEVEL
• If it is necessary to add water to the radiator, stop the engine and allow the engine
and radiator to cool down before adding the water.
• Slowly loosen the caps to relive pressure before removing the caps.
USE OF LIGHTING
When checking fuel, oil, coolant, or battery electrolyte, always use lighting with
anti-explosion specifications. If such lighting equipment is not used, there is
danger or explosion.
PRECAUTIONS WITH BATTERY

• When repairing the electrical system or when carrying out electrical welding,
remove the negative (-) terminal of the battery to stop the flow of current.
HANDLING HIGH-PRESSURE HOSES

• Do not bend high-pressure hoses or hit them with hard objects. Do not use any bent or cracked piping, tubes or
hoses. They may burst during use.
• Always repair any loose or broken fuel hoses or oil hoses. If fuel or oil leaks, it may cause a fire.
PRECAUTIONS WITH HIGH PRESSURE OIL

• Do not forget that the work equipment circuits are always under pressure.
• Do not add oil, drain oil, or carry out maintenance or inspection before completely releasing the internal pressure.
• If oil is leaking under high pressure from small holes, it is dangerous if the jet of high-pressure oil hits your skin
or enters your eyes. Always wear safety glasses and thick gloves, and use a piece of cardboard or a sheet of
wood to check for oil leakage.
• If you are hit by a jet of high-pressure oil, consult a doctor immediately for medical attention.

PRECAUTIONS WHEN CARRYING OUT MAINTENANCE AT HIGH TEMPERATURE OR HIGH PRESSURE
• Immediately after stopping operations, the engine cooling water and oil at all parts
are at high temperature and under high pressure.
In this condition, if the cap is removed, or the oil or water are drained, or the filters
are replaced, it may result in burns or other injury. Wait for the temperature to go
down, then carry out the inspection and maintenance in accordance with the
procedures given in this manual.
ROTATING FAN AND BELT

• Keep away from rotating parts and be careful not to let anything get caught in them.
• If your body or tools touch the fan blades or fan belt, they may be cut off or sent flying,
so never touch any rotating parts.
WASTE MATERIALS
• Never dump waste oil in a sewer system, rivers, etc.

• Always put oil drained from your machine in containers. Never drain oil directly
on the ground.
• Obey appropriate laws and regulations when disposing of harmful objects such
as oil, fuel, coolant, solvent, filters, batteries, and others.

TIRES
HANDLING TIRES
If tires are not used under the specified conditions, they may overheat and burst or be cut and burst by sharp stones
on rough road surfaces. This may lead to serious injury or damage.
To maintain safety, always keep to the following conditions:
• Inflate the tires to the specified pressure. Abnormal heat is generated particularly when the inflation pressure is
too low.
• Use the specified tires.
The values given in this manual for the tire inflation pressure and permissible speed are general values. The actual
values may differ depending on the type of tire and the condition under which they are used. For details, please
contact your Komatsu distributor or tire maker.
If the tires become hot, a flammable gas is produced, and this may ignite. It is particularly dangerous if the tires
become overheated when the tires are under pressure. If the gas generated inside the tire ignites, the internal pressure
will suddenly rise, and the tire will explode, and this may lead to serious personal injury. Explosions differ from
punctures or tire bursts, because the destructive force is extremely large. Therefore, the
following operations are strictly prohibited when the tire is under high internal pressure:
• Welding the rim
• Building fires or carrying out welding near the wheel or tire.
If you do not understand the proper procedure for carrying out maintenance or replacement of the wheel or tire, and
you use the wrong method, the wheel or tire may burst and cause serious injury or damage. When carrying out such
maintenance, please consult your Komatsu distributor or tire maker.
STORING TIRES AFTER REMOVAL

• As a basic rule, store the tires in a warehouse which unauthorized persons cannot enter. If the tires are stored
outside, always erect a fence around the tires and put up "No Entry" and other warning signs that even young
children can understand.
• Stand the tire on level ground, and block it securely so that it cannot roll or fall over.
• If the tire should fall over, get out of the way quickly. The tires for construction equipment are extremely heavy,
so trying to hold the tire may lead to serious injury.

OPERATING INSTRUCTIONS
PREPARING FOR OPERATION

The safest trucks are those which have been properly Local work practices may prevent an operator from
prepared for operation. At the beginning of each shift, performing all tasks suggested here, but to the extent
a careful check of the truck should be made by the permitted, the operator should follow this or similar
operator before attempting to start the engine. routine.
Vehicle breakdowns and UNSCHEDULED downtime
1. Start at left front of truck (see illustration, next
and loss of production can be reduced.
page). While performing the walk around inspec-
tion, visually inspect all lights and safety equip-
SAFETY IS THINKING AHEAD
ment for external damage from rocks or misuse.
Prevention is the best safety program. Prevent a Make sure lenses are clean and unbroken.
potential accident by knowing the employer’s safety
2. Move behind the front of the left front tire, inspect
requirements and all necessary job site regulations, as
the hub and brake assemblies for leaks and any
well as use and care of the safety equipment on the
abnormal conditions. Check that the air system
truck.
cooler is clean and not covered with mud, etc.
Only qualified operators or technicians should attempt
to operate or maintain the truck. Check that all suspension attaching hardware is
secure and inspect for evidence of wear. Check
Safe practices start before the operator gets to that the suspension extension (exposed piston
the equipment! rod) is correct, and that there are no leaks.
• Wear the proper clothing. Loose fitting clothing, 3. Inspect fan and air conditioner belts for correct
unbuttoned sleeves and jackets, jewelry, etc., can tension, obvious wear, and tracking. Inspect fan
catch on a protrusion and cause a potential haz- guard for security and condition.
ard.
4. Look overhead at bottom of cab and check for
•Always use the personal safety equipment pro- leakage of the steering control valve and/or
vided for the operator such as hard hat, safety hoses.
shoes, safety glasses or goggles. There are some
5. Move outboard of the front wheel, and inspect
conditions when protective hearing devices
attaching lugs/wedges to be sure all are tight and
should also be worn for operator safety.
complete. Check tires for cuts, damage or “bub-
• When walking to and from the truck, maintain a bles” and that inflation appears to be correct.
safe distance from all machines even if the opera-
6. Move behind the rear of the front wheel, inspect
tor is visible.
for leaks at hub or brakes or any unusual condi-
tions. Inspect suspension hardware to be sure it
is all in place. Inspect the tie-rod pivots and
At The Truck - Ground Level Walk Around
steering cylinder for proper greasing, and for se-
Inspection
curity of all parts. Inspect for any hydraulic leaks.
At the beginning of each shift, a careful walk around
7. Check pumps on front of transmission for leakage
inspection of the truck should be made before the
and that all parts are secure.
operator attempts engine start-up. A walk around in-
Also check the transmission filter for leaks.
spection is a systematic ground level inspection of the
truck and its components to insure that the truck is safe
8. Inspect sight glass
to operate before entering the operator’s cab.
for transmission oil
Start at the left front corner of the truck (see illustration, level. With engine
next page), and move in a counter-clockwise direction, stopped, hydraulic
front-to-rear, across the rear, and continuing forward fluid should be be-
up the opposite side of the truck to the original starting tween the upper
point. If these steps are taken in sequence, and are two marks.
repeated from the same point and in the same direction (Refer to decal on
before every shift, many potential problems may be transmission oil
avoided. pan.) Notify main-
tenance if oil ap-
If problems or potential problems are found during
pears to be low.
the “walk-around”, be sure to notify maintenance.

START HERE
330M "WALK-AROUND" INSPECTION
NOTE: Engine Oil and Transmission Oil levels are checked

most accurately when engine is running and all systems are
at normal operating temperatures.
Refer to Section 4, LUBRICATION & SERVICE, 10 Hour (Daily)
Inspection for these procedures.

9. Move to the 17. Move on around the right dual tires, inspect be-
side of the hy- tween the tires for rocks, and for condition of the
d rau li c ta nk rock ejector, inspect the tires for cuts or damage,
and check the and for correct inflation.
hydraulic fluid
18. Perform same inspection for wheel lugs/wedges,
levels for both
wheel cover latches, and for leaks that was done
the Steering &
on the left hand dual wheels.
Hoist tank (1) and the Brake Cooling Oil tank (2).
Oil should be visible in each sight glass with 19. Move in front of right dual tires, and inspect the
engine stopped and body down. hoist cylinder the same as was done on the left
side.
10. Move on around the hydraulic tank and in front of
the rear dual tires, inspect the hoist cylinder for 20. Move on around the fuel tank, inspect the attach-
any damage and leaks, also that lower guard is ing hardware for the fuel tank at the upper sad-
in place. Inspect both upper and lower hoist cyl- dles, and then at the lower back of the tank for the
inder pins for security, and for proper greasing. security and condition of the mounts.
11. Before leaving this position, look to see that there
is no leakage or any other unusual condition with
transmission or drive shaft.
12. Move on around the dual tires, check to see that
all lugs/wedges are in place and tight. Inspect
wheel for any leakage that may be coming from
inside the wheel housing that would indicate
planetary leakage. Inspect the fuel gauge (2) and note the quantity
Check dual tires for cuts, damage or “bubbles” indicated. Compare this indication later against
and that inflation appears to be correct. Inspect the fuel gauge reading in the instrument panel of
for any rocks that might be lodged between dual the operator cab.
tires, and that rock ejector is in good condition and 21. Move in behind the right front wheel, and inspect
straight so that it can not damage a tire. the tie-rod pivots and steering cylinder for proper
13. Inspect left rear suspension for damage and for greasing, and for security of all parts.
proper inflation, and that there are no leaks. Be sure the suspension protective cover is in
Inspect also for proper greasing, and that covers good condition. Check suspension attaching
over the chromed piston rod are in good condi- hardware and suspension extension, as well as
tion. greasing and attaching hardware for the steering
cylinder.
14. Check final drive housing breather. Replace
breather if obstructed. Check for leakage around 22. Move out and around the right front wheel, inspect
final drive housing and oil disc brake housings that all lugs/wedges are in place and tight.
and the hoses connected to the housings. 23. Move in behind the front of the right front wheel,
15. While standing behind final drive housing, look up check hub and brakes for leaks and any unusual
to see that rear lights are in good condition, along condition. Inspect the engine compartment for
with back up horns. Inspect linkage rods to see any leaks and unusual condition. Inspect the fan
that they are getting proper greasing in all pin guard, and belts also for any rags or debris behind
locations. Also look at both body hinge pins for radiator.
greasing and any abnormal condition. 24. With engine stopped, check engine oil level.
The dipsticks of some engines may be marked on
Drain moisture from both sides;
rear brake air tank by one side marked “With Engine Stopped”, and
pulling chain (1) on other side marked “With Engine Running”.
moisture drain valve. Normal check is with engine running, and at
operating temperature.
Refer to Section 4, Lubrication & Service, 10 Hour
(Daily) Inspection.
16. Perform the same inspection on the right rear Check that the engine oil filters or oil lines to filters
suspension as done on the left. are not leaking.

25. Move on around to the right front of the truck. 32. Check air cleaner
indicator (1).
26. When moving in front of the radiator, inspect for
If the RED area is
any debris that might be stuck in front of the
showing in the in-
radiator and remove it. Check for any coolant
dicator, the air fil-
leaks. Inspect all headlamps and fog lights.
t er must be
27. Before climbing ladder to first level, be sure cleaned/replac
ground level engine shutdown switch is “ON”. ed before operat-
(If truck is equipped with this feature.) ing truck.
28. Climb ladder to main deck. Always use grab rails 33. Clean cab windows and mirrors; clean out cab
and ladder when mounting or dismounting from floor as necessary. Insure steering wheel, con-
the truck. Clean ladder and hand rails of any trols and pedals are free of any oil, grease or mud.
foreign material, such as ice, snow, oil or mud.
34. Stow personal gear in cab so that it does not
interfere with any operation of the truck. Dirt or
trash buildup, specifically in the operator’s cab,
should be cleared. Do not carry tools or supplies
Always mount and dismount ladders facing the in cab of truck or on the deck.
truck. Never attempt to mount or dismount while 35. Adjust seat and steering wheel so that it is com-
the truck is in motion. fortable for use.
29. When checking coolant 36. Be familiar with all control locations and functions
in radiator, use coolant BEFORE operating truck.
level sight gauge (2). Read this “Operation - Section 3" COMPLETELY
Check that water level and be certain to understand all discussions in the
is between FULL and OPERATOR CONTROLS AND INSTRUMENT
LOW. If water is low, PANEL section.
add water though water
filler (1) to FULL level.
If engine has been running, allow coolant to cool,

before removing the fill cap or draining radiator.
Serious burns may result if coolant is not allowed
to cool.
If it is necessary to remove radiator cap, shut down
engine (if running), and relieve coolant pressure
SLOWLY before removing radiator cap. After add-
ing water tighten cap securely.
30. Inspect battery box
cover for loose-
ness or damage.
Check the brake
c h am be rs fo r
leaks, damage,
etc. Check brake
fluid level (2).
31 . Drain moisture
fro m tank s by
pulling chains (1)
on moisture drain
valves. Check air
tanks and lines
for leaks.

ENGINE START-UP SAFETY PRACTICES
Safety rules must be observed upon engine start-up. • Check that the Central Warning Lamp and
all monitor lamps and
gauges, light up for
approximately 3 sec-
onds and that the
Insure adequate ventilation before start-up, if the alarm buzzer sounds
truck is in an enclosure. for approximately 2
Exhaust fumes are dangerous! seconds.
1. Insure all personnel are clear of truck before • The speedometer should display “88".
starting engine. • If the air pressure is below normal operating
Always sound the horn as a warning before actu- pressure, the central warning lamp should
ating any operational controls. flash and the buzzer should sound.
2. Check and insure Transmission Range Selector
is in the “Neutral” position before starting. • If the Shift Lever is not at the “N” position,
the central warning
3. In cold weather, if truck is equipped with auxiliary
lamp will flash and
heaters, do not attempt to start engine while
the alarm buzzer
heaters are in operation. Damage to coolant heat-
will sound intermit-
ers will result, due to lack of circulation.
tently. When the
4. The key switch has three positions: Off, On, Start. shift lever is moved
to the “N” position,
When the key switch is rotated one the lamp will go out and the buzzer will stop.
position clockwise, it is in the “On
(run)” position and all electrical cir-
cuits (except “start”) are activated. • When checking the
monitor, check all
Before Starting The Engine caution lamps and
pilot lamps at the
same time.
Press Lamp Check Switch -
During the following safety checks, if the alarm or Check to see that all caution lamps or pilot
red warning lamp does not turn “On” as required, lamps are illuminated.
OR, if the actuation or release of any emergency • Check the Manual Emergency Steering.
control, brake, or steering circuit does not appear With the key switch
normal, shut engine down immediately and notify in the ON position,
maintenance personnel. turn emergency
Do not operate truck until the circuit in question is steering switch ON
fully operational. (red light ON), and
ch eck t hat t he
steering wheel can
Perform the following checks to be certain that the be operated. If the
central warning system, alarm buzzer, and all steering wheel cannot be operated, notify
machine monitors and lamps are functional: maintenance personnel.
Do Not Operate truck.
• Turn the key switch to the “ON” position. • Check the Auto Emergency Steering.
(Do Not Start Engine). With the key switch in
t he O N posi ti on,
NOTE: If the engine has been running, and then move Parking Brake
is stopped, the monitor cannot be checked until lever to the “OFF”
at least 30 seconds have passed. (unlocked) position.
Wait 1.5 seconds and
check that the emer-
gency steering is actuated and the steering can
be operated.

STARTING THE ENGINE
• Rotate key switch fully clock-
wise to “start” position (with
Transmission Range Selec- Electric starters and engine grid heaters can be a
tor in “Neutral”) and HOLD significant electrical drain on vehicle batteries.
this position until engine The vehicle battery charging system should be
starts (see NOTE below). monitored and maintained at all times, especially
“Start” position is spring during cold weather operation.
loaded to return to “On” when When temperature is below 3oC (38oF), do not
key is released. leave key switch “ON” (engine not operating) for
extended periods of time (i.e. troubleshooting).
NOTE: This truck is equipped with an engine prelube
system. With this feature, a noticeable time delay may
• The truck cannot be push started.
occur (while engine lube oil passages are being filled
Transmission lube and control systems are not
and pressurized) before engine cranking will begin.
operational when engine is not running.
• When getting a battery assist from one truck to
STARTING THE ENGINE IN COLD WEATHER another, use the following procedure to avoid
the possibility of causing sparks near the bat-
The truck is equipped with an Automatic Cold Start Aid tery where explosive gases may be present.
which senses intake manifold temperature and auto-
a. All switches must be “Off” prior to making any
matically turns electric grid heaters in the engine intake
connections.
manifold “On/OFF”.
b. Be certain to maintain correct polarity.
• When the key switch is turned “ON” and the
o o NOTE: 330M trucks are equipped with four 12
manifold temperature is below 3 C (38 F), the
Automatic Cold Start system will energize the volt batteries connected in series and parallel
engine intake manifold grid heaters. to provide 24 volt output. Be certain to maintain
Auto grid heater activation time (t) is: correct voltage and polarity when connecting
booster cables.
o o Damage to electrical components may result if
t1 = 15 sec @ 3 C (38 F) voltage and polarity are not correct.
o o
t2 = 30 sec @ -12 C (10 F)
c. Connect one lead of booster cable to 24V
• The heater pilot lamp positive (+) post of battery needing assist, and
(instrument panel, to right other lead of the booster cable to the 24V
of steering column) will illu- positive (+) post of auxiliary battery (power
minate during heating cy- source).
cle.
d. Connect one lead of second booster cable to
• When the light goes “out”, turn the key switch 24V negative (-) post of auxiliary battery (power
to the “Start” position and hold this position source) and then connect other lead of the
until engine starts. (See prelube NOTE above.) booster cable to a good frame ground on the
disabled truck away from the battery needing
CAUTION: Do not crank engine with an electric
assist.
starter for more than 30 seconds. Severe damage
to starter motor can result from overheating.
Allow two minutes for starter motor cooling before
attempting to start engine again.
• If engine does not start, turn key switch “Off”,

wait for at least two minutes, and repeat the
above procedure.
• Under normal conditions, there is no need to
use the Manual Cold Start Switch.
(Refer to “Instrument Panel and Indicators”,
this Section.)
If it is very cold, and the prelube runs a long
time, the manual switch can be used to main-
tain pre-heating.

AFTER ENGINE HAS STARTED
• After starting engine, operate engine at ap- 4. Check Parking Brake capacity.
proximately 1000 rpm, until engine lubricating • With the machine on flat ground, check that the
oil temperature and coolant temperature air pressure gauge is indicating “normal”
gauges are indicating “normal” (green) range. (green) range.
• Check also that the air pressure gauge is indi- • Move the Parking Brake Valve Lever to the
cating “normal” (green) range. PARKING (“locked”) position.
• Become thoroughly familiar with steering, Mo ve t he Shift
braking, and emergency controls. Lever to any posi-
tion other than “N”,
and check that the
central warning
During the following safety checks, if actuation or lamp flashes.
release of any steering, brake, or emergency con-
• Set shift lever to
trol circuit does not appear normal, shut engine
the D position, and gradually raise the engine
down immediately and notify maintenance person-
speed to 1770 rpm.
nel.
Check that the machine does not move.
Do not operate truck until circuit in question is fully If machine moves, notify maintenance person-
operational. nel to adjust parking brake.
Do not operate truck until parking brake is
fully operational.
1. Test the truck steering in extreme right and left
directions.
5. Check for normal actuation of the Emergency
Brake.
2. Check for normal actuation of the foot brake.
• With the machine on flat ground, check that the
• With the machine on flat ground,
air pressure gauge is indicating “normal”
depress Foot Brake pedal.
(green) range.
• Move Shift Lever • Move the Emergency Brake Lever to the
to the D position, BRAKE (“unlocked”) position.
and gradually raise
• Set Shift Lever to
the engine speed
the D position, and
to 1680 rpm.
gradually raise the
engine speed to
Check that the machine does not move. full throttle. Check
that the machine
does not move.
3. Check for normal actuation of the retarder. If machine moves, notify maintenance person-
• With the machine on flat ground, pull Retarder nel immediately to repair brakes.
Lever (1) fully. Do not operate truck until emergency brake
is fully operational.
• Set Shift Lever
(2) to the D posi-
tion, and gradu- 6. Check gauges, warning lights and instruments
al l y rai se t he before moving the truck to insure proper system
engine speed to operation and proper instrument functioning.
1240 rpm. Give special attention to braking and steering
circuit warning lights. If warning lights come on,
Check that the machine does not move.
shut down the engine immediately and notify
maintenance personnel to determine the cause.
7. Insure headlights, worklights and taillights are in
proper working order. Good visibility may prevent
an accident. Check operation of windshield wiper
and washer.

8. When truck body is in dump position, do not allow 5. Observe all regulations pertaining to the job site’s
anyone beneath it, unless body-up retaining de- traffic pattern. Be alert to any unusual traffic pat-
vice is in place. tern. Match the truck speed to haul road condi-
tions and slow the truck in any congested area.
9. Do not use the fire extinguisher for any purpose
Obey the spotter’s signals at shovel and dump.
other than putting out a fire! If extinguisher is
discharged, report the occurrence so the used 6. Do not allow engine to run at “Idle” for extended
unit can be refilled or replaced. periods of time.
10. Do not allow unauthorized personnel to ride in the 7. Check parking brake periodically during working
truck. Do not allow anyone to ride on the ladder shift. Use parking brake for parking and at
or on the deck of the truck. shovel and dump only.
Do not attempt to apply parking brake while truck
8. Do not leave truck unattended while engine is
is moving!
running. Shut down engine before getting out of
cab. 8. Proceed slowly on rough terrain to avoid deep ruts
or large obstacles. Avoid traveling close to soft
edges and the edge of fill area.
MACHINE OPERATION SAFETY 9. Truck operation requires concentrated effort by

the driver. Avoid distractions of any kind while
PRECAUTIONS
operating the truck.
After the truck engine is started and all systems are
functioning properly, the operator must follow all local
safety rules to insure safe machine operation.
LOADING
1. Pull into the loading area with caution. Remain at
a safe distance while truck ahead is being loaded.
If any of the red warning lights come “On” or if any 2. Do not drive over unprotected power cables.
gauge reads in the red area during truck operation, 3. When approaching or leaving a loading area,
a malfunction is indicated. Stop truck as soon as watch out for other vehicles and for personnel
safety permits, shut down engine if problem indi- working in the area.
cates and have problem corrected before resum-
ing truck operation. 4. When pulling in under a loader or shovel, follow
“Spotter” or “Shovel Operator” signals. The truck
operator may speed up loading operations by
1. Always sound the warning horn before moving the observing the location and loading cycle of the
truck. When backing the truck, give back-up sig- truck being loaded ahead, then follow a similiar
nal (three blasts on air horn); when starting for- pattern.
ward, two blasts on air horn. These signals must
be given each time the truck is moved forward or 5. Operator should remain in truck cab with engine
backward. Look to the rear before backing the running while truck is being loaded. Place Trans-
truck. Watch for and obey ground spotter’s hand mission Range Selector in “Neutral” and apply
signals before making any reverse movements. Parking Brake lever.
Spotter should have a clear view of the total area
at the rear of the truck.
2. Operate the truck only while properly seated with
seat belt fastened. Keep hands and feet inside If operator must leave truck cab during loading,
the cab compartment while truck is in operation. engine must be shut down and parking brake ap-
Keep a firm grip on steering wheel at all times. plied. DO NOT use emergency brake for parking.
Remain far enough away from truck to avoid being
3. Check that all mirrors are not damaged, clean,
struck by flying material.
and are properly positioned for optimum view.
4. Check gauges and instruments frequently during
operation for proper readings. 6. When truck is loaded, pull away from shovel as
quickly as possible, but with extreme caution.

HAULING
1. Always stay alert! If unfamiliar with the road, drive If the Brake Oil Temperature exceeds this limit,
with extreme caution. move the transmission range selector lever to a
lower gear and use the foot-operated service
2. Govern truck speed by the road conditions, brakes to reduce the truck ground speed. This will
weather and visibility. allow the transmission to shift to the next lower
3. Operate truck so it is under control at all times. gear range for more efficient cooling.
4. Use extreme caution when approaching a haul If the Brake Oil Temperature continues to exceed
road intersection. Maintain a safe distance from 248°F (120°C), select a safe area out of the way
oncoming vehicles. of other traffic, stop the truck, move the transmis-
sion range selector lever to the Neutral (N) posi-
5. Obey all road signs. tion, and operate the engine at approximately
6. Always dim headlights when meeting oncoming 1200 RPM until the Brake Oil Temperature gauge
vehicles. registers in the "green" range.
7. Maintain a safe distance when following another For better control under dry road conditions, the
vehicle. Never approach another vehicle from the optional front wheel brakes may be turned on.
rear, in the same lane, closer than 15 m (50 ft).
When operating on a down grade, stay at least 30
m (100 ft) away.
8. During normal operation, the retarder control
lever should be used to control the speed of the
truck and to stop the truck instead of using the
foot-operated service brake pedal. Use of this
lever allows the operator to apply the REAR
oil-cooled brakes only, thus extending the life
of the front caliper disc pads while still maintaining
maximum control of the truck. The foot-operated
brake pedal should be used when maneuvering
in tight places, at the shovel and dump, and when
quick stops or severe braking is required.
Retarder Operation
Before starting down a grade, maintain a speed
that will insure safe driving and provide effective
retarding under all conditions.
Refer to the "Retarding Capacity" decal which is
applied to the upper left-hand corner of the cab
windshield. This decal is designed to help the
operator maintain a safe vehicle speed while
descending a grade with a loaded truck.
For efficient retarder operation, the operator
should: 9. When operating truck in darkness or when visibil-
• Preselect a ground speed and gear range for a ity is poor, do not move truck unless headlights
known grade that will permit continous retarder are on. Do not back truck if back-up horn or lights
operation within the LIMITS OF THE CHART. are inoperative.
• Maintain engine RPM between 1800 — 2400 10. When backing the truck, give back-up signal
RPM, and (three blasts on air horn); when starting forward,
two blasts on air horn. These signals must be
• Observe the Brake Oil Temperature gauge to given each time the truck is moved forward or
make certain the Brake Oil Temperature does not backward.
exceed 248°F (120°C).

11. Do not stop or park on a haul road unless unavoid- To Raise dump body:
able. If you must stop, move truck to a safe place,
apply parking brake, shut down engine, block
wheels securely and notify maintenance person-
nel for assistance.
12. If the “Emergency Steering” light and/or “Low Air The dumping of very large rocks (10% of payload,
Pressure” warning light come on during opera- or greater) or sticky material (loads that do not flow
tion, steer the truck immediately to a safe stop- freely from the body) may allow the material to
ping area, away from other traffic if possible. move too fast and cause the body to move RAP-
Refer to item 11 above. IDLY and SUDDENLY. This sudden movement may
jolt the truck violently and cause possible injury to
13. Report haul road conditions immediately. Muddy the operator, and/or damage to the hoist cylinders,
or icy roads, pot holes or other obstructions can frame, and/or body hinge pins. If it is necessary to
present hazards. dump this kind of material, refer to the CAUTION
14. Cab doors should remain closed at all times while in the following procedure:
truck is in motion or unattended.
15. Check for flat tires periodically during shift. If truck 4. Pull dump lever up to the
has been run on a “flat”, it must not be parked “RAISE” position and release
in a building until the tire cools. lever.
PASSING
5. Raise engine RPM to accelerate hoist speed.
1. Do not pass another truck on a hill or blind curve! Refer to the CAUTION below. When body is near
2. Before passing, make sure the road ahead is the maximum angle, reduce engine RPM (reduce
clear. If a disabled truck is blocking your lane, foot pressure on the accelerator pedal) to reduce
slow down and pass with extreme caution. shock load to the hydraulic system and hoist
cylinders.
3. Use only the areas designated for passing.
DUMPING
1. Pull into dump area with extreme caution. Make
If dumping very large rocks or sticky material as
sure area is clear of persons and obstructions,
decribed in WARNING above, slowly accelerate
including overhead utility lines. Obey signals di-
engine RPM to raise body.
rected by the spotter, if present.
When the material starts to
Avoid unstable areas. Stay a safe distance from move, move hoist lever to
edge of dump area. “HOLD” position. If material
Position truck on a solid, level surface before does not continue moving and
dumping. clear body, repeat this proce-
dure until material has cleared
body.
6. When the dump body rises to the set position

As body raises, the truck Center of Gravity (CG) (adjusted position of body positioner) dump lever
will move. TRUCK MUST BE ON LEVEL SURFACE returns to the “HOLD” position. If desired to raise
to prevent tipping / rolling! the body further, move dump lever to raise posi-
tion and dump will rise. If dump lever is released,
lever will return to hold position. Dump body will
2. Carefully maneuver truck into dump position. stop in that position.
When backing truck into dump position, use only
the foot-operated brake pedal to stop and hold 7. After material being dumped clears body, lower
truck. body to frame.
3. When in dump position, place transmission range

selector at the “Neutral” position, and apply the
Park Brake lever/switch.

To Lower Body: SAFE PARKING PROCEDURES
7. After material being dumped The operator must continue the use of safety precau-
clears body, move dump tions when preparing for parking and engine shut-
lever to the “LOWER” posi- down.
tion and dump body will start
to move down. In the event that the equipment is being worked in
consecutive shifts, any questionable truck perform-
8. Release the lever and it will ance the operator may have noticed must be checked
return automatically to the by maintenance personnel before the truck is released
“ FLOAT” position. The to another operator.
body will move down under 1. The truck should be parked on level ground, if at
its own weight. all possible. If parking must be done on a grade,
the truck should be positioned at right angles to
If dumped material builds up at body tailgate and the grade.
body cannot be lowered, shift Transmission
Range Selector to “D” (Drive), release park brake 2. The parking brake must be applied and/or chocks
lever, and drive forward to clear material. Stop, placed fore/aft of wheels so that the truck cannot
shift Transmission Range Selector to “N” (Neu- roll. Each truck should be parked at a reasonable
tral), apply park brake lever and lower body. See distance from another.
NOTE : * below. 3. Haul roads are not safe parking areas. In an
emergency, pick the safest spot most visible to
other machines in the area. If the truck becomes
disabled where traffic is heavy, mark the truck
with warning flags in daylight or with flares at
night.
The truck is not to be moved with
the dump body raised except for
emergency moves only. Failure
to lower body before moving SHUTDOWN PROCEDURE
truck may cause damage to hoist
cylinders, frame and/or body The following sequence of shutdown procedure is
hinge pins. important and should be followed at each shutdown.
NOTE: When traveling, always place the dump lever

at the FLOAT position, regardless of whether or not 1. Stop truck, reduce engine RPM to low idle. Place
the truck is loaded. Transmission Range Selector in “Neutral” and
* If the transmission range selector is moved to any apply parking brake.
position other than “N” (neutral) when the dump lever 2. Allow engine to cool gradually by running at low
is not at the FLOAT position, the central warning lamp idle for 3 to 5 minutes.
will flash and the alarm buzzer will sound intermittently.
3. Turn keyswitch “Off” to stop engine.
9. With body returned to frame, move Transmission 4. Close and lock all windows, remove key from key
Range Selector to “D” (Drive), release park brake switch and lock cab to prevent possible unauthor-
lever, and leave dump area carefully. ized truck operation. Dismount truck properly.

TOWING
Prior to towing a truck, many factors must be carefully 3. If the engine is NOT operable, never haul the truck
considered. Serious personal injury and/or significant over 800m (2,625 ft).
property damage may result if important safety prac- If the towing distance surpasses that limit, be sure
tices, procedures and preparation for moving heavy to remove the drive shaft between the transmis-
equipment are not observed. sion and the differential case (if final drive sun
gears have not been removed).
The towing speed must not be greater than 8 km/h
(5 mph).
Both right and left planetary sun gears/drive axles
should be removed before any towing. Refer to 4. Inspect tow bar for capacity (it should be strong
Section “G” in the Service Manual for these in- enough to tow 1.5 times the gross vehicle weight
structions. Extensive secondary damage can oc- of truck being towed).
cur to final drive components and/or transmission, 5. Determine that towing vehicle has adequate ca-
if truck is towed without first removing sun pacity to both move and stop the towed truck
gears/drive axles. under all conditions.
6. Protect both operators in the event of tow bar
failure.
7. Release disabled truck brakes and remove all
blocking.
The truck must not be towed except in emergen- Do not tow the truck any faster than 8 kph (5 MPH).
cies.
When towing becomes necessary, use the tow hook 8. Sudden movement may cause tow bar failure.
installed under the front frame and take the following Smooth and gradual truck movement is preferred.
precautions: 9. Minimize tow angle at all times - NEVER EXCEED
o
30 .
1. Block disabled truck to prevent movement while The towed truck must be steered in the direction
attaching tow bar. of the tow bar.
2. If the engine is operable; keep the engine running
while towing the machine, so that the steering and
braking can be used.
If there is a failure in the air circuit, the brakes
cannot be used, so be extremely careful when
towing. When air pressure in air reservoir abnor-
mally drops due to leakage from air circuit, park- BRAKE RELEASE
ing brake and emergency brake are actuated.
When towing truck, both brakes must be re- Releasing Parking Brake And Emergency Brake
leased. Refer to “BRAKE RELEASE” following After Being Actuated In An Emergency
these" TOWING" instructions.
If the pressure inside the air tank drops abnormally due
If the engine is NOT operable, it is possible to to some problem, such as leakage of air from the air
steer using the emergency steering, but do not circuit, the parking brake and emergency brake are
use it for more than 90 seconds, and travel at a automatically actuated.
speed of less than 5 km/h (3 mph).

RELEASE OF PARKING BRAKE
The parking brake is a dry disc brake mounted on the Refer to Section 4, Lubrication & Service, Parking
rear drive shaft at the differential input with two (2) Brake Inspection and Adjustment, for instructions for
spring-applied, air-released calipers. Each caliper is reconnecting and adjusting park brake.
individually applied/released through separate air
chamber actuators (spring cylinder assemblies). If the
parking brake can not be released after its emergency
application – even if the parking brake valve lever is RELEASE OF EMERGENCY BRAKE
put in RELEASE position – take the following actions When the emergency brake has been applied, do not
to release the parking brake: continue to drive the machine. This will cause seizure
of the brake discs and linings.
If the emergency brake can not be released after its
emergency application – even if the emergency brake
valve lever is put in RELEASE position – release the
emergency brake in the following manner:
Before releasing the air pressure from the emergency
brake reservoir, confirm safety in the surrounding area
and put chocks against the tires.
1. Block disabled truck to prevent movement and

confirm safety in the surrounding area.
2. At the parking brake relay valve, remove both air
hoses (4) connected to the air chambers of the
parking brake spring cylinder assemblies (5).
3. Connect these hoses together using a “tee” fitting
with compatible thread ends.
4. Connect third connector of “tee” to a hose from RELEASING EMERGENCY BRAKE
an air supply of sufficient capacity to release 1. Air Quick Disconnect 2. Drain Valve
calipers. Apply air and release brake. Pull Rings
5. With parking brake released, turn adjustment bolt
(2) counterclockwise, and check for “play” in link-
1. After making preparations to tow the machine, pull
age (3). Remove pin (1). Repeat for other caliper.
rings (2) on the 4 drain valves on the front air tanks
Disconnect air supply.
to release the air pressure.
6. With parking brake disconnected, remove block-
2. After exhausting all air pressure, release rings (2).
ing and immediately move the truck to a safe
place. Refer to INSTRUCTIONS FOR TOWING 3. Drain the rear air tank by pulling and holding the
THE MACHINE. ring on the air drain valve mounted on the frame
in front of the right rear suspension. Keep drain
valve open until all air is exhausted from tank.
This will allow the emergency brake to release.
If the air system is not operating, the service

brakes will not apply; this is very dangerous. Be
sure to tow the truck at low speed, keeping the
engine running (if possible) and always be ready
to steer.

NOTES

WARNINGS AND CAUTIONS
The following paragraphs give an explanation of the WARNING, CAUTION, and Service Instruction plates and decals
attached to the truck. The plates and decals listed here are typical of this model, but because of customer options,
individual trucks may have plates and decals that are different from those shown here.
The plates and decals must be kept clean and legible. If any decal or plate becomes worn or unable to be read, it
should be replaced with a new one.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
This caution plate is located inside the cab on the left-hand door panel under the arm rest. It contains (3) CAUTIONS
- Operating Machine Safely, Driving Over A Long Distance, and Hoist Control Lever operation. These decals stress
the importance of reading and understanding the operators manual prior to the operation of equipment.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TIRE AIR PRESSURE Caution plate is located inside

the cab on left-hand door panel under the arm rest.
Extreme caution should be used when taking a pres-
sure reading. Tire is under high pressure.
A04028 11/98 Warnings and Cautions A4-1

This instruction plate contains (4) WARNINGS -
Inspection and Maintenance With Body In Raised Up
Position, Emergency Steering System Operation, the
Engine Shut Down Procedure, and the Retarder Oil
Temperature Warning Light.
These “ WARNINGS” stress the importance of reading
and understanding the operators manual prior to the
operation of equipment.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Caution plates are mounted at the air tank on center

top deck, also at rear frame just below tail light assem-
blies. Caution should be used when opening drain
valves. System under high pressure.
. . . . . . . . . . . . . . . . . . . . . . .
DANGER plates are mounted on each suspension
cylinder. These plates warn that the suspensions are
charged with high pressure nitrogen. No servicing of
any kind should be attempted until the service manual
has been referenced and proper and safe procedures
are followed.
A Brake Cooling Oil decal is located between the filler

cap and sight gauge on the right hand side of the
hydraulic tank.
A4-2 Warnings and Cautions A04028 11/98

This CAUTION plate is located on left hand side of
radiator shroud. Extreme care should be taken when
working around fan and belts. Hands and loose articles
A CAUTION plate is attached to the hydraulic tank, of clothing should be kept away when machine is
alerting the service person that the engine must always operating.
be shut down and cooled before removing fillercap. . . . . . . . . . . . . . . . . . . . . . . .
This plate also alerts the service person of HOT oil
under pressure. Hydraulic oil becomes heated and
pressurized during operation. Care must be taken to
avoid burns when it is necessary to open the hydraulic
system.
Hydraulic fluid escaping under pressure can have

sufficient force to enter a person’s body by pene-
trating the skin and cause serious injury and pos-
sible death if proper medical treatment by a
A plate is mounted on the left hand side of the trans-
physician familiar with this injury is not received
mission oil pan to provide instructions for proper trans-
immediately.
mission oil level check.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Steering and Hoist Oil decal is located to the left of the A Caution plate is located next to the sight gauge on
left hand filler cap on left hand side of hydraulic tank. the front brake oil tank, mounted on air tank top right
hand deck. The Caution plate alerts service person to
use only SAE-10W oil.
Brake system components are not compatible with
other fluids which can cause component deterioration.

A service indicator plate is located on the center air
cleaner housing.
A plate is located next to filler cap on fuel cap which Service filter element when red signal reaches service
specifies Diesel Fuel Only. Care should be taken to level in dust indicator.
open cap slowly and bleed off pressure that may be in
tank when removing filler cap.
Operation and Maintenance Manual refered to is from
Engine Manufacturer. When using compressed air, wear safety glasses
. . . . . . . . . . . . . . . . . . . . . . . and all other safety equipment required when
cleaning.
. . . . . . . . . . . . . . . . . . . . . . .
Attached to the interior of battery box lid is a DANGER

plate. This plate stresses the need to keep from mak-
ing any sparks near the battery. When another battery
or 24VDC power source is used for auxiliary power, all
switches must be “Off” prior to making any connec-
tions. When connecting auxiliary power cables, posi-
tively maintain correct polarity; connect the positive (+)
leads together and then connect the negative (-) lead
of the auxiliary power cable to a good frame ground.
Do not connect to the negative post of the truck battery
or near the battery box. This hookup completes the
circuit but minimizes danger of sparks near the batter-
ies.
Sulfuric acid is corrosive and toxic. Use proper safety
gear, goggles, rubber gloves and rubber apron when
handling and servicing batteries. Avoid contact with
skin, eyes or clothing. In event of accident, immedi-
ately flush with plenty of water and call a physician. A caution plate is located on the right hand inside door
KEEP OUT OR REACH OF CHILDREN! panel and also on the lid of the battery box. These
instructions must be followed when welding is done on
the truck to avoid damage to the electronic compo-
nents.

A Caution plate is located next to the sight gauge on
A Caution plate is located on center deck floor next to the radiator cooling water reserve tank on top of right
radiator fill access cover plate. When actual tempera- hand deck just aft of battery box.
ture differs with the indication, change the ratio of
antifreeze to match ambient conditions. Keep coolant level between “FULL” and “LOW”
when engine is cold.
Service personnel should use caution when serv-
icing radiator. The system is pressurized because . . . . . . . . . . . . . . . . . . . . . . .
of thermal expansion of coolant. “DO NOT” re-
move radiator cap while engine is hot. Severe
burns may result.
. . . . . . . . . . . . . . . . . . . . . .
The Action Code decal is located on the inside of the

Warning plates are mounted on the truck frame in front
cab in the upper left-hand corner of the windshield.
of and to the rear of both front tires to alert all persons
This decal explains what action to take when an action
to stay clear when the truck is being steered.
code is displayed on the monitor panel on the operator
monitor and indicator panel.

An informational plate for solenoid valve and relays is mounted to the inside lid of the electrical console behind the
operator and passenger seats.
A "Retarding Capacity" decal is applied to the upper left-hand corner of the cab windshield. This decal is designed
to help the operator maintain a safe vehicle speed while descending a grade with a loaded truck.
For efficient retarder operation, the operator should:

• Preselect a ground speed and gear range for a
known grade that will permit continous retarder
operation within the LIMITS OF THE CHART.
• Maintain engine RPM between 1800 — 2400
RPM, and
• Observe the Brake Oil Temperature gauge to
make certain the Brake Oil Temperature does not
exceed 248°F (120°C).
If the Brake Oil Temperature exceeds this limit, move
the transmission range selector lever to a lower gear
and use the foot-operated service brakes to reduce the
truck ground speed. This will allow the transmission to
shift to the next lower gear range for more efficient
cooling.
If the Brake Oil Temperature continues to exceed
248°F (120°C), select a safe area out of the way of
other traffic, stop the truck, move the transmission
range selector lever to the Neutral (N) position, and
operate the engine at approximately 1200 RPM until
the Brake Oil Temperature gauge registers in the
"green" range.

An informational plate for the fuse table is located to the left of the solenoid valve and relay plate. This is mounted
inside of lid of the electrical console behind the operator and passenger seats.
A product identification plate is located on left hand front fender on the inside top. This lists the vehicle model number,
maximum G.V.W. and Product Identification Number. The Product Identification Number (vehicle serial number)
contains information which will identify the original manufacturing bill of material for this unit. This complete number
will be necessary for the proper ordering of many service parts and/or warranty consideration.

The lubrication chart is located on the left hand front fender behind the ladder. Refer to Section P, "Lubrication and
Service", for more complete lubrication instructions.

STANDARD TABLES
This manual provides dual dimensioning for many specifications. Metric units are specified first, with U.S. standard
units in parentheses. References throughout the manual to standard torques or other standard values will be to one
of the following Tables.
For values not shown in any of the charts or tables, standard conversion factors for most commonly used
measurements are provided in the conversion table below.
INDEX OF TABLES
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page
TABLE ISTANDARD TIGHTENING TORQUE COMMON CONVERSIONS
. . . . . . . For Capscrews and Nuts A5-2 TO CONVERT
MULTIPLY BY
FROM TO
millimeter (mm) inch – in. 0.0394
TABLE IISTANDARD TIGHTENING TORQUE centimeter (cm) inch – in. 0.3937
. . . . . . . . . . For Split Flange Bolts A5-2 meter (m) foot – ft. 3.2808
meter (m) yard – yd. 1.0936
kilometer (km) mile – mi. 0.6210
TABLE III . . . . . TIGHTENING TORQUE FOR sq. centimeters (cm2) sq. in. – in.2 0.1550
sq. centimeters (cm2) sq. ft. – ft.2 0.001
. . Flared Tube And Hose Fittings A5-2 3
cu. centimeters (cm ) cu. in. – in.3 0.061
liters (l) cu. in. – in.3 61.02
cu. meters (m3) cu. ft. – ft.3 35.314
TABLE IV TEMPERATURE CONVERSIONS A5-3 liters (l) cu. ft. – ft.3 0.0353
grams (g) ounce – oz. 0.0353
milliliter (ml) fluid ounce – fl. oz. 0.0338
TABLE V . . . . . . TORQUE CONVERSIONS kilogram (kg) pound (mass) 2.2046
. . kilogram.meters To foot pounds A5-3 Newton (N) pound (force) – lbs. 0.2248
Newton.meters (N.m) kilogram.meters (kg.m) 0.102
Newton.meters (N.m) ft. lbs. (force) 0.7376
TABLE VI . . . . . . TORQUE CONVERSIONS kilogram.meters (kg.m) ft. lbs. (force) 7.2329
kilogram.meters To Newton.meters A5-3 kilogram.meters (kg.m) Newton.meters (N.m) 9.807
kilopascals (kPa) psi (pressure) 0.1450
megapascals (MPa) psi (pressure) 145.038
TABLE VII . . . . PRESSURE CONVERSIONS kilograms/cm2 (kg/cm2) psi (pressure) 14.2231
2 kilograms/cm2 (kg/cm2) kilopascals (kPa) 9.8068
. . . . . . . . . . . kg/cm To (psi) A5-4
kilogram (kg) ton (short) 0.0011
metric ton ton (short) 1.1023
liters (l) quart – qt. 1.0567
TABLEVIII . . . . PRESSURE CONVERSIONS liters (l) gallon – gal. 0.2642
2
. . . . . . . . . . . . kg/cm To kPa A5-4 Watts HP (horsepower) 0.00134
kilowatts (kW) HP (horsepower) 1.3410
TABLE IX . . . PRESSURE CONVERSIONS

. . . . . . . . . . . . . . . . psi To kPa A5-4
A05002 9/97 Standard Tables A5-1

TABLE I
STANDARD TIGHTENING TORQUE FOR
METRIC HEX HEAD CAPSCREW AND NUT ASSEMBLY
Capscrew Thread Width Kilogram.meters Newton.meters Foot Pounds

Diameter Across Flat (kg.m) (N.m) (ft.lbs.)
(mm) (mm) Tolerances ±10% Tolerances ±10% Tolerances ±10%
6 10 1.35 13.2 10
8 13 3.2 31.4 23
10 17 6.7 65.7 48
12 19 11.5 112 83
14 22 18.0 177 130
16 24 28.5 279 206
18 27 39.0 383 282
20 30 56.0 549 405
22 32 76.0 745 550
24 36 94.5 927 684
27 41 135 1320 975
30 46 175 1720 1266
33 50 225 2210 1630
36 55 280 2750 2025
39 60 335 3280 2420
This Table represents standard values only.
Do not use these values to replace torque values which are specified in the Service Manual instructions.
TABLE II
TIGHTENING TORQUE FOR SPLIT FLANGE BOLTS
Capscrew Thread Width Kilogram.meters Newton.meters Foot Pounds

Diameter Across Flat (kg.m) (N.m) (ft.lbs.)
10 14 6.7 65.7 48
12 17 11.5 112 83
16 22 28.5 279 206
This Table represents standard values only.
Do not use these values to replace torque values which are specified in the Service Manual instructions.
TABLE III
TIGHTENING TORQUE FOR FLARED TUBE AND HOSE FITTINGS
Thread Diameter Width Kilogram.meters Newton.meters Foot Pounds

of Nut Across Flat (kg.m) (N.m) (ft.lbs.)
14 19 2.5 25 18
18 24 5 50 36
22 27 8 80 58
24 32 14 140 101
30 36 18 175 130
33 41 20 195 145
36 46 25 245 180
42 55 30 295 215
A5-2 Standard Tables A05002 9/97

TABLE IV TEMPERATURE CONVERSIONS
FORMULA: F° – 32 ÷ 1.8 = C° C° x 1.8 + 32 = F°
CELSIUS FAHRENHEIT CELSIUS FAHRENHEIT CELSIUS FAHRENHEIT
C° F° C° F° C° F°
121 250 482 63 145 293 4 40 104
118 245 473 60 140 284 2 35 95
116 240 464 57 135 275 –1 30 86
113 235 455 54 130 266 –4 25 77
110 230 446 52 125 257 –7 20 68
107 225 437 49 120 248 –9 15 59
104 220 428 46 115 239 – 12 10 50
102 215 419 43 110 230 – 15 5 41
99 210 410 41 105 221 – 18 0 32
96 205 401 38 100 212 – 21 –5 23
93 200 392 35 95 293 – 23 – 10 14
91 195 383 32 90 194 – 26 – 15 5
88 190 374 29 85 185 – 29 – 20 –4
85 185 365 27 80 176 – 32 – 25 – 13
82 180 356 24 75 167 – 34 – 30 – 22
79 175 347 21 70 158 – 37 – 35 – 31
77 170 338 18 65 149 – 40 – 40 – 40
74 165 329 15 60 140 – 43 – 45 – 49
71 160 320 13 55 131 – 46 – 50 – 58
68 155 311 10 50 122 – 48 – 55 – 67
66 150 302 7 45 113 – 51 – 60 – 76
NOTE: The numbers in the unmarked columns refer to temperature in either degrees Celsius (C°) or Fahrenheit, F°. Select a number in
this unmarked column and read to the left to convert to degrees Celsius (C°) or read to the right to convert to degrees Fahrenheit, F°.
If starting with a known temperature (either C° or F°), find that temperature in the marked column and read the converted temperature in the
center, unmarked column.
TABLE V TORQUE CONVERSIONS

kilogram.meter - kg.m To Foot Pounds – (ft.lbs.)
1 kg.m = 7.2339 ft.lbs.
kg.m 0 1 2 3 4 5 6 7 8 9
0 (ft. lbs.) 7.23 14.5 21.7 28.9 36.2 43.4 50.6 57.9 65.1
10 72.3 79.6 86.8 94.0 101.3 108.5 115.7 123.0 130.2 137.4
20 144.7 151.9 159.1 166.4 173.6 180.8 188.1 195.3 202.5 209.8
30 217.0 224.2 231.5 238.7 245.9 253.2 260.4 267.6 274.9 282.1
40 289.3 296.5 303.8 311.0 318.2 325.5 332.7 339.9 347.2 354.4
50 361.6 368.9 376.1 383.3 390.6 397.8 405.0 412.3 419.5 426.7
60 434.0 441.2 448.4 455.7 462.9 470.1 477.4 484.6 491.8 499.1
70 506.3 513.5 520.8 528.0 535.2 542.5 549.7 556.9 564.2 571.4
80 578.6 585.9 593.1 600.3 607.6 614.8 622.0 629.3 636.5 643.7
90 651.0 658.2 665.4 672.7 679.9 687.1 694.4 701.6 708.8 716.1
TABLE VI TORQUE CONVERSIONS

kilogram.meter - kg.m To Newton.meters (N.m)
1 kg.m = 9.807 N.m
kg.m 0 1 2 3 4 5 6 7 8 9
0 (N.m) 9.8 19.6 29.4 39.2 49.0 58.8 68.6 78.5 88.3
10 98.1 107.9 117.7 127.5 137.3 147.1 156.9 166.7 176.5 186.3
20 196.1 205.9 215.8 225.6 235.4 245.2 255.0 264.8 274.6 284.4
30 294.2 304.0 313.8 323.6 333.4 343.2 353.1 362.9 372.7 382.5
40 392.3 402.1 411.9 421.7 431.5 441.3 451.1 460.9 470.7 480.5
50 490.4 500.2 510.0 519.8 529.6 539.4 549.2 559.0 568.8 578.6
60 588.4 598.2 608.0 617.8 627.6 637.5 647.3 657.1 666.9 676.7
70 686.5 696.3 706.1 716.0 725.7 735.5 745.3 755.1 764.9 774.8
80 784.6 794.4 804.2 814.0 823.8 833.6 843.4 853.2 863.0 872.8
90 882.6 892.4 902.2 912.1 921.9 931.7 941.5 951.3 961.1 970.9

TABLE VII PRESSURE CONVERSIONS
kilograms/cm2 (kg/cm2) To pounds per sq. in. (psi)
1 kg/cm2 = 14.2231 psi
kg/cm2 0 1 2 3 4 5 6 7 8 9
0 (psi) 14.2 28.4 42.7 56.9 71.1 85.3 99.6 113.8 128.0
10 142.2 156.5 170.7 185.0 199.1 213.3 227.6 241.8 256.0 270.2
20 284.5 298.7 312.9 327.1 341.4 355.6 369.8 384.0 398.2 412.5
30 426.7 440.9 455.1 469.4 483.6 497.8 512.0 526.3 540.5 554.7
40 568.9 583.1 597.4 611.6 625.8 640.0 654.3 668.5 682.7 696.9
50 711.2 725.4 739.6 753.8 768.0 782.3 796.5 810.7 824.9 839.2
60 853.4 867.6 881.8 896.1 910.3 924.5 938.7 952.9 967.2 981.4
70 995.6 1009.8 1024.1 1038.3 1052.5 1066.7 1081.0 1095.2 1109.4 1123.6
80 1137.8 1152.1 1166.3 1180.5 1194.7 1209.0 1223.2 1237.4 1251.6 1265.9
90 1280.1 1294.3 1308.5 1322.7 1337.0 1351.2 1365.4 1379.6 1393.9 1408.1
TABLE VIII PRESSURE CONVERSIONS

kilograms/cm2 (kg/cm2) To kilopascals (kPa)
1 kg/cm2 = 9.8068 kPa
kg/cm2 0 1 2 3 4 5 6 7 8 9
0 (kPa) 9.81 19.6 29.4 39.2 49.0 58.8 68.6 78.5 88.3
10 98.1 107.9 117.7 127.5 137.3 147.1 156.9 166.7 176.5 186.3
20 196.1 205.9 215.7 225.6 235.4 245,2 255.0 264.8 274.6 284.4
30 294.2 304.0 313.8 323.6 333.4 343.2 353.0 362.9 372.7 382.5
40 392.3 402.1 411.9 421.7 431.5 441.3 451.1 460.9 470.7 480.5
50 490.3 500.1 510.0 519.8 529.6 539.4 549.2 559.0 568.8 578.6
60 588.4 598.2 608.0 617.8 627.6 637.4 647.2 657.1 666.9 676.7
70 686.5 696.3 706.1 715.9 725.7 735.5 745.3 755.1 764.9 774.7
80 784.5 794.4 804.2 814.0 823.8 833.6 843.4 853.2 863.0 872.8
90 882.6 892.4 902.2 912.0 921.8 931.6 941.5 951.3 961.1 970.9
TABLE IX PRESSURE CONVERSIONS

Pounds/sq. in. [psi] To kilopascals (kPa)
Formula: psi x 6.895 = kPa
PSI 0 1 2 3 4 5 6 7 8 9
0 (kPa) 6.895 13.79 20.68 27.58 34.47 41.37 48.26 55.16 62.05
10 68.95 75.84 82.74 89.63 96.53 103.42 110.32 117.21 124.1 131.0
20 137.9 144.8 151.7 158.6 165.5 172.4 179.3 186.2 193.1 200.0
30 206.8 213.7 220.6 227.5 234.4 241.3 248.2 255.1 262.0 268.9
40 275.8 282.7 289.6 296.5 303.4 310.3 317.2 324.1 331.0 337.9
50 344.7 351.6 358.5 365.4 372.3 379.2 386.1 393.0 399.9 406.8
60 413.7 420.6 427.5 434.4 441.3 448.2 455.1 462.0 468.9 475.8
70 482.6 489.5 496.4 503.3 510.2 517.1 524.0 530.9 537.8 544.7
80 551.6 558.5 565.4 572.3 579.2 586.1 593.0 599.9 606.8 613.7
90 620.5 627.4 634.3 641.2 648.1 655.0 661.9 668.8 675.7 682.6
NOTE: Tables such as Table V, VI, VII, VIII, and IX may be used as in the following example:
Example: Convert 955 kg.m to foot pounds (ft.lbs.).
1. Select Table V. 4. Go to kg.m row 0, column 5; read 49.0

5 kg.m = 49 ft.lbs. Add to step 3.
2. Go to kg.m row 90, column 5; read 931.7
95 kg.m = 931.7 ft.lbs. 5. 950 +5 kg.m = 9317 +49 = 9366 ft.lbs.
955 kg.m = 9366 ft.lbs.
3. Multiply by 10:
950 kg.m = 9317 ft.lbs.

The sealants and adhesives listed below are manufactured and sold by Three Bond U.S.A., Inc.
For information concerning Three Bond products, call or write to:
Three Bond U.S.A., Inc.

6184 Schumacher Park Drive
West Chester, OH 45069
Telephone: (513) 779-7300
Fax: (513) 779-7375
SEALANTS AND ADHESIVES

Nomenclature Code Three Bond Applications
LT-1A TB1521 Used to apply rubber pads, rubber gaskets and cork plugs.
Used to apply resin, rubber, metallic and non-metallic
LT-1B 1000B - 1000W
parts when a fast, strong seal is needed.
LT-2 TB1374 Preventing bolts, nuts and plugs from loosening and leaking oil.
Adhesives
LT-2A TB2411 Preventing bolts, nuts and plugs from loosening and leaking oil. (1)
LT-2B TB2403 Preventing bolts, nuts and plugs from loosening and leaking oil. (2)
LT-2C TB2430 or TB2440 Preventing bolts, nuts and plugs from loosening and leaking oil. (2)
LT-3 Main bond TB2001
Provides an airtight, electrically insulating seal. Used for aluminum surfaces.
Hardening agent TB2105
LG-1 TB1108B Used with gaskets and packings to increase sealing effect.
LG-3 TB1107 Heat-resistant gasket for precombustion chambers and exhaust piping.
Liquid Gasket Used by itself on mounting surfaces on the final drive and transmission
LG-4 TB1104
cases. Thickness after tightening: 0.07-0.08 mm (0.0027-0.0032 in)
Used by itself to seal grease fittings, tapered screw fittings and tapered
LG-5 TB1110
screw fittings in hydraulic circuits of less than 50 mm (2 in ) in diameter.
Antifriction Applied to bearings and taper shafts to facilitate press-fitting
LM-P --
compound and to prevent sticking, burning or rusting.
Applied to bearings, sliding parts and oil seals for lubrication,
Grease G2-LI --
rust prevention and facilitation of assembling work.
Vaseline -- -- Used for protecting battery electrode terminals from corrosion.
(1) Used for threaded areas (for example, plug, nipple, elbow etc.) which are removable and a pressure of 20
2
kg/cm (285 psi) or less.
2
(2) Used for threaded areas (for example, stud, etc.) which are not removable and a pressure of 20 kg/cm (285
psi) or less.
PART NUMBERS
THREE BOND KOMATSU
TB1374 09940-00030
TB1521 790-129-9030
TB1104 790-129-9020
TB1108B 790-129-9010

NOTES

STANDARD VALUE TABLES
ENGINE STANDARD VALUES

MODEL 330M
ENGINE SA12V140Z-1
ITEM MEASUREMENT CONDITIONS UNIT Std. Value Permissible Value
Power Mode 2350 ±50 2350 ±50
High Idle rpm
Economy Mode 2300 ±50 2300 ±50
Engine HI 1000 ±50 1000 ±50
Speed Low Idle rpm
Lo 650 ±25 650 ±25
Power Mode 2000 ±50 2000 ±50
Rated Speed rpm
Economy Mode 1900 ±50 1900 ±50
A06002 Standard Value Tables A6-1

CHASSIS STANDARD VALUES
MEASUREMENT STANDARD PERMISSIBLE
ITEM UNIT
CONDITIONS VALUE VALUE
TRUCK PERFORMANCE
F1 6.6 ±5% 6.6 ±5%
F2 9.3 ±5% 9.3 ±5%
• Engine water temperature.: Within op
F3 erating range. 12.4 ±5% 12.4 ±5%
Travel • Transmission oil temperature:
F4 MPH 16.6 ±5% 16.6 ±5%
Speed 70 °- 90°C
F5 • Empty truck 22.0 ±5% 22.0 ±5%
F6 • Traveling resistance: 3.3% 30.0 ±5% 30.0 ±5%
F7 40.0 ±5% 40.0 ±5%
R 7.1 ±5% 7.1 ±5%
ENGINE SPEED
Shift up 2100 ±50 2100 ±50
Automatic Shift
High
Power 1450 ±50 1450 ±50
Control
Mode Shift down 1400 ±50 1400 ±50

(F2→F1 only) (F2→F1 only)
Shift up RPM 2000 ±50 2000 ±50
Economy 1350 ±50 1350 ±50
Mode Shift down 1300 ±50 1300 ±50
(F2→F1 only) (F2→F1 only)
Braking Shift up 2450 ±50 2450 ±50
• Engine water temp.: Within operating
Mode Shift down range. 1550 ±50 1550 ±50
• Transmission oil temp.: 70° - 90°C
F1, F2 1500 1500
Set • Hydraulic oil temp.: 70° - 90°C
Auto Lock-up
F3 — F7 • “Braking Mode” refers to when the 1250 ±50 1250 ±50

F1, F2 accelerator is OFF or the rear brake is 1200 1200
ON. RPM
Reset
F3 — F7 1100 ±50 1100 ±50
Set 2600 ±10 2600 ±10

Protection
Overrun
RPM
Reset 2350 ±10 2350 ±10
Same as shift down Same as shift down

Down-shift Inhibitor RPM for automatic shift for automatic shift
control (see above) control (see above)
TORQUE CONVERTER
POWER MODE
• Transmission oil temp.: 70° - 90°C
Engine Speed at Torque Converter • Hydraulic oil temp.: 70° - 90°C RPM 2040 ±100 2040 ±100
Stall • Engine water temp.:within operating ECONOMY MODE
range
RPM 1950 ±75 1950 ±75
A6-2 Standard Value Tables A06002

CHASSIS STANDARD VALUES (Cont.)
PERMISSIBLE
ITEM MEASUREMENT CONDITIONS UNIT STD. VALUE
VALUE
ACCELERATOR PEDAL
(Electronic (Electronic
Starting to depress governor governor
Operating • Operating effort at a point kg specification truck) specification truck)
effort 150 mm (5.9 in.) from pedal fulcrum (lbs)
1.8 ±0.5 1.8 ±0.5
Fully depressed
(4.0 ±0.7) (4.0 ±0.7)
42.1 +2.0 42.1 +2.0
−4.9 −4.9
Starting to depress +.07
• Travel at a point 150 mm (5.9 in.) mm (1.6 ) (1.6 +.07 )
Travel −.19 −.19
from pedal fulcrum (inches)
44 ±5 44 ±5
↔ Fully
(1.7 ±.2) (1.7 ±.2)
GEARSHIFT LEVER
1.6 ±0.4 Max. 2
Operating effort • At center of lever knob kg (lbs.)
(3.5 ±0.8) (4.4)
R— N
N— D
D— 5 mm 18.5 ±1 18.5 ±2
Travel
(inches) (0.73 ±.04) (0.73 ±.08)
5— 4
4— 3
3— L
TORQUE CONVERTER
Oil pressure Engine @ high idle 8 ±1 (113 ±15) 8 ±1 (113 ±15)
at inlet port • Oil temperature:
Engine @ low idle 1.3 ± .5 (18.5 ±7) 1.3 ± .5 (18.5 ±7)
70° - 90°C (158° - 194°F)
Oil pressure Engine @ high idle 4 ± .5 (57 ±14) 4 ± .5 (57 ±14)
2
at outlet port • Engine water temperature: kg/cm
Engine @ low idle 1.0 ± .5 (14 ±7) 1.0 ± .5 (14 ±7)
Within operating temperature (psi)
Lock-up oil Engine @ high idle 16.0 ± .5 (230 ±10) 16.0 ± .5 (230 ±10)
pressure • Hydraulic oil temperature:
Engine @ low idle 16.0 ± .5 (230 ±10) 16.0 ± .5 (230 ±10)
50° - 80°C (122° - 176°F)
Main relief Engine @ high idle 39.0 ± 2 (555 ±29) 39.0 ± 2 (555 ±29)
pressure Engine @ low idle 34.5 ± 2 (490 ±29) 34.5 ± 2 (490 ±29)
TRANSMISSION CONTROL VALVE SET PRESSURE
L, H, 4th Engine @ high idle 16.5 ±1.5 (235 ±20) 16.5 ±1.5 (235 ±20)
on actual truck
clutch Engine @ low idle 16.5 ±1.5 (235 ±20) 16.5 ±1.5 (235 ±20)
Engine @ high idle 20.5 ±1.5 (290 ±20) 20.5 ±1.5 (290 ±20)
3RD clutch
Engine @ low idle 20.5 ±1.5 (290 ±20) 20.5 ±1.5 (290 ±20)
• Oil temperature:
Engine @ high idle 70° - 90°C (158° - 194°F) 31.5 ±1.5 (450 ±20) 31.5 ±1.5 (450 ±20)
1st, 2nd clutch
Engine @ low idle 2 31.5 ±1.5 (450 ±20) 31.5 ±1.5 (450 ±20)
• Engine water temperature: kg/cm
Engine @ high idle Within operating temperature (psi) 30 ±1.5 (435 ±20) 30 ±1.5 (435 ±20)
R clutch
Engine @ low idle 30 ±1.5 (435 ±20) 30 ±1.5 (435 ±20)
• Hydraulic oil temperature:
17 ±2 (242 ±28) 17 ±2 (242 ±28)
modulation Checker
Engine @ high idle 50° - 80°C (122° - 176°F)

L, 4th clutch
Engine @ low idle 17 ±2 (242 ±28) 17 ±2 (242 ±28)
When using
Engine @ high idle 20 ±2 (284 ±28) 20 ±2 (284 ±28)

H, 3rd clutch
Engine @ low idle 20 ±2 (284 ±28) 20 ±2 (284 ±28)
1st, 2nd, R Engine @ high idle 33 ±2 (469 ±22) 33 ±2 (469 ±22)

clutch Engine @ low idle 33 ±2 (469 ±22) 33 ±2 (469 ±22)

ITEM UNIT
TRANSMISSION
• Engine water temperature.: Within
operating range.
• Engine: Full throttle 2
kg/cm 1.25 ±0.5 1.25 ±0.5
Lubricating Oil Pressure • Oil temp.: 60° - 80°C (140° - 176°F) (psi) (18 ±7) (18 ±7)
(using EO10-CD) or
70 ° - 90°C (158° - 194°F)
(using EO30-CD)
TIRE INFLATION PRESSURE
27.00 R49
7.0 ±0.1 7.0 ±0.1
Standard Tires (front and rear
wheels) 2 (100 ±2) (100 ±2)
kg/cm
• When empty (psi)
27.00-49-48PR
5.60 5.60
Optional Tires (front and rear
(80) (80)
wheels)
STEERING WHEEL
• Oil temp.: 50° - 80°C (122° - 176°F)
Operating Force (Steering wheel turn- • Truck stopped and empty. If impossible kg Max. 3.0 Max. 3.6
ing speed: 30 rpm) when truck is stopped, travel at low (lbs.) (Max 6.6) (Max 8.0)
speed with engine @ low idle.
• Length at circumference of steering
mm 130 ±30 130 ±30
Play wheel.
(in.) (5 ±1.2) (5 ±1.2)
• Engine stopped
No. of Turns • Lock → Lock Turns 3.5 ±0.4 3.5 ±0.6
Left → Right • Oil temp.: 50° - 80°C (122° - 176°F) Max. 4 Max. 5
Turning Time • Engine speed: Full lrange sec.
Right → Left • Lock → Lock Max. 4 Max. 5
STEERING VALVE
210 +15 210 +15
−0.0 −0.0
Engine @ Hi idle +215
• Oil temp.: 50° - 80°C (122° - 176°F) 2 (2986 ) (2986 +215 )
kg/cm −0.0 −0.0
Relief Pressure • Engine: Fulll throttle (psi) +10
• Demand valve relief valve 185 185 +10
−0.0 −0.0
Engine @ Lo idle +140
(2630 ) (2630 +140 )
−0.0 −0.0
BRAKE PEDAL
kg
Operating Force Max 30 (Max. 66) Max 30 (Max. 66)
• Tip of pedal (lbs.)
Travel mm (in.) 78 ±8 (3 ±0.3) 78 ±15 (3 ±0.6)
RETARDER CONTROL LEVER
kg 1.0 - 4.0 0.5 - 6.0
Operating Force
• At point 10 mm (0.4 in) from tip of lever (lbs.) (2.2 - 8.8) (1.1 - 13.2)
Travel degrees 0 - 90 ±3 0 - 90 ±3
PARKING BRAKE LEVER
kg Max. 2.0 3.0
Operating Force • Tip of lever (lbs.) (Max. 4.4) (6.6)
EMERGENCY BRAKE LEVER
kg 0.01 - 0.02 Max. 0.05
Operating Force • Tip of lever (lbs.) (0.02 - 0.04) (Max. 0.10)
AIR GOVERNOR
• Pressure at which air is stored and 2
circuit is unloaded when air pressure is kg/cm 8.3 ±0.3 8.3 ±0.3
Set pressure
raised from 0 kg/cm2 (0 psi) with engine (psi) (120 ±4.3) (120 ±4.3)
at full throttle.

ITEM UNIT
BRAKES
Service 91 ton payload Max. 29 (95) Max. 29 (95)
brake
braking Empty Max. 22.3 (73) Max. 22.3 (73)
distance • Initial speed: 32 km/h (20 MPH) m
• Distance from starting speed to stop (ft)
Retarder 91 ton payload • Max. actuating air pressure: Max. 29 (95) Max. 38 (125)
brake 8.3 kg/cm2 (120 psi)
braking Empty • Max. hydraulic pressure: Max. 22.3 (73) Max. 30 (98)
distance Rear: 45 kg/cm2 (640 psi)
Front chamber Front: 187 kg/cm2 (2660 psi) Min. 160 (2275) Min. 160 (2275)
Brake • On flat, dry road surface 2
Rear chamber kg/cm
actuating Min. 45 (640) Min. 45 (640)
(service) (psi)
pressure
Rear chamber
Min. 45 (640) Min. 45 (640)
(retarder)
• Carrying 91 ton payload
Stopping distance when m
emergency brake is applied •
Initial speed: 32 km/h (20 mph) Max. 60.9 (200) Max. 60.9 (200)
(ft)
• On flat, dry road surface
PARKING BRAKE
• With 91 ton payload
Braking Capacity (sin θ) • After adjusting clearance between disc % Min. 15 Min. 15
and pad
• F2
Starting Test rpm Min. 2070 Min. 2070
• Torque converter stall
HOIST LEVER
HOLD →
Max. 10 (22) Max. 10 (22)
RAISE
RAISE →
Automatically reset Automatically reset
HOLD
HOLD →
Operating kg 5 - 10 (11 - 22) 5 - 10 (11 - 22)
Force
FLOAT • Center of control lever knob (lbs.)
FLOAT →
3 - 6 (7- 13) 3 - 6 (7- 13)
HOLD
LOWER →
Automatically reset Automatically reset
FLOAT
FLOAT →
Max. 13 (29) Max. 13 (29)
LOWER
RAISE → 15 ±2 15 ±2
HOLD (A) (0.6 ±.07) (0.6 ±.07)
HOLD → (Refer to Figure 6-1 for hoist lever mm 11 ±2 11 ±2
Travel
FLOAT (B) positions “A”, “B”, and “C”) (in.) (0.4 ±.07) (0.4 ±.07)
FLOAT → 11 ±2 11 ±2
LOWER (C) (0.4 ±.07) (0.4 ±.07)
HOIST VALVE
Engine @ 200 +15 200 +15

−0.0 −0.0
• Oil temp.: 50° - 80°C (122° - 176°F) +210
Hgh Idle 2 (2845 ) (2845 +210 )
Relief • Engine: Fulll throttle kg/cm −0.0 −0.0
Pressure • Measure at end of stroke when raising (psi)
185 +10 185 +10
Engine @ body −0.0 −0.0
Low Idle (2630 +142 ) (2630 +142 )
−0.0 −0.0

ITEM UNIT
BODY
Lifting Speed • Oil temp.: 50° - 80°C (122° - 176°F) 13 ±1.5 13 ±1.5
• Engine: Full throttle sec.
Lowering Speed • Use FLOAT when lowering 17 ±1.5 17 ±1.5
• Oil temp.: 50° - 80°C (122° - 176°F)

Hydraulic Drift • Set with No. 2 cylinder extended mm (in.) Max. 85 (3.4) 170 (6.7)
200 mm (7.8 in.)
• Hydraulic drift after 5 minutes
SUSPENSION CYLINDER
A
• On flat road surface 262 ±10 (10.3 ±0.4) 262 ±10 (10.3 ±0.4)
Installed Front mm
Length B • When empty (in.) 484 ±10 (19 ±0.4) 484 ±10 (19 ±0.4)
Rear A 242 ±10 (9.5 ±0.4) 242 ±10 (9.5 ±0.4)
Front (Refer to Figure 6-2 for dimension “A” and
2 39.5 ±5 (561 ±70) 539.5 ±5 (561 ±70)
Pressure “B” locations.) kg/cm
Rear (psi) 26.0 ±5 (370 ±70) 26.0 ±5 (370 ±70)
CHECKING BRAKE PERFORMANCE

Service Brake • F2 Min. 1930 Min. 1930
Retarder Brake • Torque converter stall Min. 1540 Min. 1540
• Engine water temperature within
Emergency Brake operating range Min. 1930 Min. 1930
2
• Air pressure: 8.3 kg/cm (120 psi) RPM
• Transmission oil temperature:
Parking Brake 70 ° - 90°C (158° - 194°F) Min. 2070 Min. 2070
• Hydraulic oil temperature:
° - 80°C (122° - 176°F)
50
FIGURE 6-1. HOIST LEVER POSITIONS FIGURE 6-2. SUSPENSION CYLINDERS

STANDARD VALUES FOR ELECTRICAL PARTS
CONNECTOR MEASUREMENT
COMPONENT COMPONENT TEST TABLE
No. CONDITIONS
ENGINE CONTROLLER
Verify normal voltages listed below: 1. Turn key switch ON.
Accelerator at Approx.
2. Insert T-adapter.
FULL position Between 3.55 - 3.75 V
Accelerator Sensor AS2
Accelerator at B-C Approx. 3. Accelerator LO ↔
LOW position .35 - .55 V FULL.
1. Turn key switch
Verify normal resistances listed below:
OFF.
Engine Water Approx.
CT1 Water Temp. 25°C (normal) 2. Disconnect CT1.
Temperature Sensor Between 9 K - 10 KΩ
A-B Approx.
Water temp. 100° C
.62 K - .65 KΩ
TRANSMISSION CONTROLLER
Engine Oil Pressure Verify normal voltages listed below: 1. Start engine.
EP1
Sensor Between B - C Aproximately 1.1 - 2.1 V 2. Insert T-adapter.
Verify normal voltages listed below: 1. Turn key switch ON.

Voltage Value 2. Insert T-adapter.
When Selected Not Selected
Between (3) - (2) [R] >1.0 V < 15.0 V
Shifter Lever SF (male) Between (4) - (2) [N] >1.0 V < 15.0 V
Between (5) - (2) [D] >1.0 V < 15.0 V
Between (6) - (2) [5] >1.0 V < 15.0 V
Between (7) - (2) [4] >1.0 V < 15.0 V
Between (8) - (2) [3] >1.0 V < 15.0 V
Between (9) - (2) [L] >1.0 V < 15.0 V
Between (1) - (2) 11.0 - 13.0 V
Verify normal resistance value listed below:

1. Turn key switch
HPS (male)
OFF.
LPS (male) 5 - 25Ω 2. Insert T-adapter.
Pressure Control Valve Between (1) - (2)
Solenoid Note: resistance should be 13.85Ω ±5% at
RPS (male
20°C (68 °F)
1PS (male)
2PS (male)
3PS (male)
4PS (male)
1. Turn key switch

Lock-up Solenoid L/CT (male) OFF.
Between (1) - (2) 30 - 80Ω 2. Disconnect L/CT
1. Turn key switch

Exhaust Brake Solenoid SL5 (male) OFF.
Between (1) - (2) 20 - 60Ω 2. Disconnect SL5.

No. CONDITIONS
TRANSMISSION CONTROLLER (Con.t)
1. Turn key switch
Rear Brake (Overrun Verify normal resistance value listed below:
SL4 (male) OFF.
Protection) Solenoid
Between (1) - (2) 20 - 60Ω 2. Disconnect SL4.
1. Turn key switch

OFF.
Transmission Oil Oil Temperature Measure Resistance 2. Disconnect SL5.
SL5 (male)
Temperature Sensor
Normal temperature:
Between 37 k- 50 kΩ
25°C (77°C)
(1) - (2)
100°C (212°F) 3.5 k - 4.0 kΩ

R01 - R29
Relay (Check as Between (1) - (2) 100 - 500Ω Check as individual
(Except
Individual Part) part
R09, R11) Between (3) - (4) <0.1 Ω
Between (1) - (2) >1 MΩ

Relay (Check as Between (5) - (6) 100 - 500Ω Check as individual
R09 - R11
Individual Part) part
Between (3) - (6) <0.1 Ω
Between (3) - (5) >1 MΩ
1. Turn key switch

HSW (male)
OFF.
2. Disconnect switch
LSW (male)
connector
Fill Switch RSW (male) Verify normal resistances listed below:

Between (1) and
1SW (male) Switch OFF >1 MΩ
chassis
2SW (male)
3SW (male)
4SW (male)
Verify normal voltage listed below: 1. Start engine.

Alternator
Alternator Terminal R - Engine running @ 1/2 throttle or above: 27.5 - 29.5 V
Chassis (NOTE: If the battery is old or after starting in cold areas, voltage may not
rise for some time.)
1. Turn key switch

OFF.
2 Approx. 160 Ω or less,

Air Pressure Sensor SR5 (male) Air Pressure:8.3 kg/cm 2. Disconnect SR5.
(120 psi) or approx. 320 Ω
Between (1) - (2)
2 Approx. 640 Ω or
Air Pressure:5.2 kg/cm
(75 psi) approx. 800 Ω

No. CONDITIONS
TRANSMISSION CONTROLLER (Cont.)
1. Turn key switch
OFF.
Engine Water
CT1 Normal temperature:
Temperature Sensor Between Approx. 9 - 10Ω 2. Disconnect CT1.
25°C (77°C)
A-B
100°C (212°F) Approx. 0.62 - 0.65Ω
Torque Converter Oil TC.SE 1. Turn key switch

Temperature Sensor (male) OFF.
Normal temperature: 2. Disconnect TC.SE,
Retarder Oil 64 Between 37 k- 50 kΩ
25°C (77°C) and 64.
Temperature Sensor (male) (1) - (2)
100°C (212°F) 3.5 k - 4.0 kΩ
1. Turn key switch

61 OFF.
Fuel Level Sensor
(male) Full Approx 12Ω or less 2. Disconnect 61.
(1) - sensor flange
Empty Approx. 85 - 110Ω
Transmission Shaft 1. Turn key switch

Speed Sensors OFF.
Input Shaft N1 (male) Between (1) - (2) 500 - 1000Ω 2. Disconnect N1 - N3.
Intermediate Shaft N2 (male) Between (1) - (2) 500 - 1000Ω
Output Shaft N3 (male) Between (1) - (2) 500 - 1000Ω
1. Turn key switch

E12 Verify normal resistance listed below:
Engine Speed Sensor OFF.
(male)
Between (1) - (2) 500 - 1000Ω 2. Disconnect E12
1. Turn key switch

Verify no continuity in circuit as listed below:
OFF.
Steering Oil 21 Normal oil

Temperature Sensor (male) temperature: 25°C No continuity 2. Disconnect 21
Between B and chassis (77°C)
Oil temperature:
No continuity
>123°C (250°C)
1. Turn key switch

Verify normal conditions in circuit as listed below:
OFF.
Air pressure
AS3 2
Retarder Switch Min.: 1.4 kg/cm Continuity 2. Disconnect AS3
(male) (20 psi)
Between (1) - (2)
Air pressure
2
Max.: 0.6 kg/cm No continuity
(8.5 psi)

No. CONDITIONS
1. Turn key switch
OFF.
Air pressure
AS5 2
Service Brake Switch Min.: 0.6 kg/cm Continuity 2. Disconnect AS5
(male) (8.5 psi)
Between (1) - (2)
Air pressure
2
(3 psi)
1. Turn key switch

OFF.
Air pressure
Emergency Brake AS4 2
Min.: 4.9 kg/cm No continuity 2. Disconnect AS4
Switch (male) (70 psi)
Between (1) - (2)
Air pressure
2
Max.: 3.7 kg/cm Continuity
(53 psi)
1. Turn key switch

OFF.
Air pressure
AS2 2
Parking Brake Switch Min.: 5.7 kg/cm Continuity 2. Disconnect AS2
(male) (81 psi)
Between (1) - (2)
Air pressure
2
(53 psi)
1. Turn key switch

OFF.
RH2 Dump lever @
Body FLOAT Switch No continuity 2. Disconnect RH2
(male) FLOAT
Between (1) - (2) Dump lever at a
position other than Continuity
FLOAT
1. Turn key switch

DB1 OFF.
Body Seated Switch
(male) Body seated No continuity 2. Disconnect DB1
Between (1) - (2)
Body not seated Continuity
1. Turn key switch

SR3 OFF.
Tilt Sensor
(male) Tilt 17° or more No continuity 2. Disconnect SR3
Between (1) - (2)
Tilt 13° or less Continuity
1. Turn key switch

OFF.
RH2 Dump lever @
Body RAISE Switch No continuity 2. Disconnect RH2
(male) RAISE
Between (7) - (8) Dump lever at a
position other than Continuity
RAISE

No. CONDITIONS
1. Turn key switch
Transmission Filter 52 OFF.
Clogging Sensor (male) Filter normal No continuity 2. Disconnect 52.
Between (1) - (2)
Filter clogged Continuity
1. Turn key switch

OFF.
BLSR(male)
Brake Stroke Switch 2. Disconnect BLSR,
BLSL (male) Stroke normal Continuity
Between (1) - (2) BLSL.
Large stroke No continuity
1. Turn key switch

OFF.
Air pressure
AS4 2
Exhaust Brake Switch Min.: 3.7 kg/cm Continuity 2. Disconnect AS4
(male) (53 psi)
Between (1) - (2)
Air pressure
2
Max.:3.3 kg/cm No continuity
(47 psi)
Relay
Emergency Steering
terminal 78 - Engine running: Minimum 20 V 1. Start engine.
Timer Relay
chassis
SUSPENSION CONTROLLER
1. Turn key switch
OFF.
Radiator Water Level 03 Radiator water level
Switch (male) Continuity 2. Disconnect 03.
normal
Between (1) - (2)
Radiator water level
No continuity
abnormal
1. Turn key switch

PW OFF.
Power Mode Switch
(male) Switch ON Continuity 2. Disconnect PW.
Between (2) - (4)
Switch OFF No continuity
1. Remove sensor
Verify normal resistances listed below: from suspension
cylinder.
FR Suspension 63 Between each connector -
500 - 1000Ω 2. Insert T-adapter.
Pressure Sensor (male) (3) - chassis
3. Verify there is no
FL Suspension 62 open or shorted
Pressure Sensor (male) circuit in wiring
harness.
4. Turn key switch ON.
1. Turn key switch

Transmission Output N3 Verify normal resistance in circuit as listed below:
OFF.
Shaft Speed Sensor (male)
Between (1) - (2) 500 - 1000Ω 2. Disconnect N3.

No. CONDITIONS
SUSPENSION CONTROLLER (Cont.)
1. Turn key switch
OFF.
Air pressure
Emergency Brake AS4 2
Min.: 4.9 kg/cm No continuity 2. Disconnect AS4.
Switch (male) (70 psi)
Between (1) - (2)
Air pressure
2
Max.:3.7 kg/cm Continuity
(52 psi)
1. Turn key switch

OFF.
Air pressure
AS5 2
Service Brake Switch Min.: 0.6 kg/cm No continuity 2. Disconnect AS5.
(male) (8.5 psi)
Between (1) - (2)
Air pressure
2
Max.:0.2 kg/cm Continuity
(.82 psi)
1. Turn key switch

SH OFF.
Shift Limit Switch
(male) Switch ON Continuity 2. Disconnect SH.
Between (2) - (4)
SL1 1. Turn key switch

(male) OFF.
SL2 2. Disconnect SL1,
Between (1) - (2) 20 - 60Ω
Suspension Control (male) SL2, SL3.
Solenoid Valve 3. Put black pole of
tester in contact
SL3
with (1); put red
(male)
pole in contact with
(2).
1. Turn key switch

OFF.
RH2
Body FLOAT Switch Lever @ FLOAT No continuity 2. Disconnect RH2.
(male)
Lever @ position other than Between (7) - (9)
Continuity
FLOAT.
PAYLOAD METER
1. Remove sensor
FR Suspension 39
from suspension
Pressure Sensor (male)
cylinder.
FL Suspension 13
Verify voltages are within the range as listed below: 2. Insert T-adapter.
RR Suspension 63 Between each connector open or shorted
Approximately 0.45 - 1.50 V
Pressure Sensor (male) (3) - chassis circuit in wiring
harness.
FL Suspension 62

No. CONDITIONS
PAYLOAD METER (Cont.)
1. Park truck on level
Verify voltage is within the range as listed below:
ground.
Clinometer PM3 open or shorted
Between (1) - (2) Approximately 2.1 - 3.1 V circuit in wiring
harness.
3. Insert T-adapter.
CHASSIS MONITOR
Verify voltage is within the range as listed below: 1. Disconnect terminal.
Engine Oil Pressure 27
Sensor (male) Between B - C Approximately 1.1 - 2.1 V 2. Insert T-adapter.
3. Start engine.
Verify voltage is within the range as listed below: 1. Start engine.

Alternator
Alternator terminal R - Engine running @ 1/2 throttle or above: 27.5 - 29.5 V
chassis (NOTE: If the battery is old or after starting in cold areas, voltage may not
raise for some time.)
1. Turn key switch

Verify (normal) resistances listed below:
OFF.
SR5 2 Approx. 160 Ω or less,

Air Pressure Sensor Air Pressure:8.3 kg/cm 2. Disconnect SR5.
(male) (120 psi) or approx. 320 Ω
Between (1) - (2)
2 Approx. 640 Ω or
Air Pressure:5.2 kg/cm
(75 psi) approx. 800 Ω
Engine Water CT1 1. Turn key switch

Verify (normal) resistance value listed below:
Temperature Sensor (male) OFF.
Torque Converter Oil TC.SE Normal temperature: 2. Disconnect CT1,
Approx. 9 - 10Ω
Temperature Sensor (male) 25°C (77°C) Between TC.SE, and 64.
Retarder oil 64 (1) - (2)
100°C (212°F) Approx. 0.62 - 0.65Ω
Temperature Sensor (male)
1. Turn key switch

Verify (normal) resistances listed below:
61 OFF.
Fuel Level Sensor
(male) Full Approx 12Ω or less 2. Disconnect 61.
(1) - sensor flange
Empty Approx. 85 - 110Ω
1. Turn key switch

Transmission Output N3 Verify normal resistance in circuit as listed below:
OFF.
Shaft Speed Sensor (male)
Between (1) - (2) 500 - 1000Ω 2. Disconnect N3.
Verify normal conditions in circuit as listed below: 1. Start engine.

Transmission Filter 52
Clogging Sensor (male) Filter normal Continuity 2. Disconnect 52.
Between (1) - (2)
Filter clogged No continuity

No. CONDITIONS
CHASSIS MONITOR (Cont.)
1. Turn key switch
Caution Pilot Lamp GK1 OFF.
Bulb Check Switch (male) Switch ON Continuity 2. Disconnect GK1
Between (1) - (2)
1. Turn key switch

EXH OFF.
Exhaust Brake Switch
(male) Switch ON Continuity 2. Disconnect EXH
Between (2) - (4)
1. Turn key switch

A1 OFF.
AISS Switch
(male) Switch ON Continuity 2. Disconnect A1.
Between (2) - (4)
Between 1. Turn key switch

Switch OFF.
Mode Change Switch 1 Terminals Switch ON Between Switch Continuity
MS11 - Terminals
MS12 Switch OFF MS11 - MS12 No continuity
Between 1. Turn key switch

Switch OFF.
Mode Change Switch 2 Terminals Switch ON Between Switch Continuity
MS21 - Terminals
MS22 Switch OFF MS21 - MS22 No continuity
1. Turn key switch

HAZ OFF.
Hazard Switch
(male) Switch ON Continuity 2. Disconnect HAZ.
Between (2) - (4)
1. Turn key switch

FL OFF.
Fog Lamp Switch
(male) Switch ON Continuity 2. Disconnect FL.
Between (2) - (4)
1. Turn key switch

FB OFF.
Front Brake Cut Switch
(male) Switch ON Continuity 2. Disconnect FB.
Between (2) - (4)

No. CONDITIONS
CHASSIS MONITOR (Cont.)
1. Turn key switch
Verify normal conditions in circuits as listed below:
OFF.
Lamp switch ON Continuity 2. Disconnect CM
Between (5) - (7)
Lamp switch OFF No continuity
Lamp switch ON Between (5) - (6), Continuity

Lamp switch OFF (6) - (7) No continuity
Comination Switch CM (male)
Turn signal lamp at LEFT Continuity
Between (3) - (8)
Turn signal lamp at N No continuity
Turn signal lamp at RIGHT Continuity

Between (3) - (4)
Turn signal lamp at N No continuity
Dimmer switch at high

Between (2) - (7) Continuity
beam
Dimmer switch at low beam Between (1) - (7) No continuity
PMC SYSTEM
Air Cleaner Clogging MM13
Sensor (male) Air cleaner normal Between (1) and Continuity 2. Disconnect MM13
Air cleaner clogged chassis No continuity

Full-flow Filter clogging MM10
Sensor (male) Filter normal Between (1) and Continuity
Filter clogged chassis No continuity

Hydraulic Filter 54
Between (1) - (2)

Hydraulic Retarder 53
Between (1) - (2)
1. Turn key switch

MM9 OFF.
Engine Oil Level Sensor
(male) Engine Oil level normal Continuity 2. Disconnect MM9
Between (1) - (2)
Engine Oil level abnormal No continuity
1. Turn key switch

OFF.
Hydraulic Oil Level MM14
Sensor (male) Hydraulic Oil level normal Continuity 2. Disconnect MM14
Between (1) and
Hydraulic Oil level chassis No continuity
abnormal

No. CONDITIONS
PMC SYSTEM (Cont.)
1. Turn key switch
Retarder Oil Level MM15 OFF.
Sensor (male) Retarder oil level normal Between (1) Continuity 2. Disconnect MM15
Retarder oil level abnormal and chassis No continuity

MM12
Brake Oil Level Sensor Brake oil level normal Continuity 2. Disconnect MM12
(male) Between (1) - (2)
Brake oil level abnormal No continuity

Battery Electrolyte MM11 Battery electrolyte level
4 V or above 2. Disconnect MM11
Level Sensor (male) normal Between (1) -
Battery electrolyte level chassis or (-) terminal
0V
abnormal

MM19
(male) 2. Disconnect MM19
Retarder Wear Sensor No retarder wear Continuity
MM20 and MM20
Between (1) - (2)
(male) 3. Actuate retarder
Retarder wear No continuity
brake.
1. Turn key switch

OFF.
AS5 2
Service Brake Switch Air pressure 0.6 kg/cm No continuity 2. Disconnect AS5.
(male) (8.5 psi) or above
Between (1) - (2)
2
Air pressure 0.2 kg/cm Continuity
(2.8 psi) or above
2
Emergency Brake AS4 Air pressure 4.9 kg/cm No continuity 2. Disconnect AS4.
Switch (male) (70 psi) or above
Between (1) - (2)
2
Air pressure 3.7 kg/cm Continuity
(52 psi) or above
Transmission Input N1 1. Turn key switch

Verify normal resistance in circuit as listed below:
Shaft Speed Sensor (male) OFF.
Transmission Output N3 2. Disconnect N1 and
Between (1) - (2) 500 - 1000 Ω
Shaft Speed Sensor (male) N3.
1. Turn key switch

E12 Verify normal resistance in circuit as listed below:
Engine Speed Sensor B OFF.
(male)
Between (1) - (2) 500 - 1000 Ω

No. CONDITIONS
PMC SYSTEM (Cont.)
1. Remove sensor
Verify normal voltage in circuit as listed below: from suspension
cylinder.
FR Suspension 39 Between (3) and chassis Approximately 0.45 - 1.50 V 2. Insert T-adapter.
open or short circuit
in wiring harness.
1. Remove sensor
Verify normal voltage in circuit as listed below: from suspension
cylinder.
FL Suspension 13 Between (3) and chassis Approximately 0.45 - 1.50 V 2. Insert T-adapter.
open or short circuit
in wiring harness.

NOTES

SECTION B
STRUCTURES
INDEX
STRUCTURAL COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-1

GRILLE AND HOOD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-1
DECKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-1
LEFT DECK STRUCTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-2
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-2
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-2
RIGHT DECK STRUCTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-3

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-3
CENTER DECK STRUCTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-4

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-4
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-4
DUMP BODY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-2
BODY PADS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-3

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-3
Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-3
BODY GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4
BODY-UP PIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4
ROCK EJECTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4

Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4
FUEL TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2
Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2
VENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2
QUICK FUEL OPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2
B01014 Index B1-1

NOTES
B1-2 Index B01014

STRUCTURAL COMPONENTS
GRILLE AND HOOD Installation
1. Install deck in reverse order to removal. Tighten
Removal all hardware to standard torque.
1. Remove grille.
2. Attach lifting device to the radiator hood. DECKS
3. Disconnect air horn hoses and headlight wire on The truck left and right decks are mounted to the frame
the left side of the radiator. structure using rubber mounting pads. These pads are
placed between the deck and the mounting structure
4. Remove the three plugs, capscrews, and nuts to reduce noise and vibration. These rubber mounts
from across the top of the radiator hood that should be checked periodically and worn or defective
secures it to the cross brace below. mounts should be replaced.
5. Remove six (6) mounting capscrews at the base The center deck section of the truck is rigidly mounted
of the radiator hood. in the front and rubber mounted in the rear.
6. Lift radiator hood off of truck.
7. Check the number of shims under hood mounting
so all shims can be placed back to their original
location during installation.
FIGURE 2-1. DECK LAYOUT
1. Capscrew 4. Right Deck 7. Capscrew 10. Cab

2. Capscrew 5. Center Deck 8. Front Grill 11. Walkway
3. Cab Mounting 6. Engine Lid 9. Ladder Deck
Capscrews
B02011 9/97 Structural Components B2-1

5. Mark shims (4) so they will be installed in the same
location when the cab and deck are installed.
The anti-slip material on the decks should be in-

spected and maintained for the safety of all per-
Installation
sonnel.
1. Lower cab and deck section onto truck and align
The decks of the trucks are also covered with anti-slip
capscrew mounting holes. Remove lifting device.
surfaces. These anti-slip coverings should be kept
clean and replaced as they become worn. 2. Adjust left hand deck rubber mounts;
a. Temporarily assemble the mounting parts with-
LEFT DECK AND CAB out shims.
b. Measure dimension "a" (Figure 2-2) at four (4)
Removal
places on each mounting pad as shown.
1. Disconnect the ground wire between the negative c. Add shims to the side where dimension "a" is
terminal of the batteries and the frame. largest, and adjust so that the difference be-
2. Remove capscrews (2, Figure 2-2) and washers tween dimension "a" at the four places is within
from each corner of the left deck section. 0.5 mm (0.02 in.).
3. Disconnect all electrical wiring, air lines, and 3. Tighten capscrews to 35-43.5 kg.m (254-315
hydraulic lines that would interfer with the removal ft.lbs.) torque.
of the cab deck.
4. Attach lifting device with wood blocks (5,Figure
2-3) and lift deck section up and away from truck.
FIGURE 2-2. RUBBER MOUNTING PADS (LEFT

DECK) FIGURE 2-3. CAB AND DECK
1. Cover 5. Rubber Mounting 1. Cab 4. Door
2. Capscrew 6. Flatwasher 2. Strap 5. Wood Block
3. Special Washer 7. Nut 3. Lifting Device
4. Shims
B2-2 Structural Components B02011 9/97

RIGHT DECK Installation
Removal
1. Lower deck section onto truck and align capscrew
mounting holes.
1. Disconnect the ground wire between the negative
2. Remove lifting device and
terminal of the batteries and the frame.
3. Install capscrews (2, Figure 2-4) and washers.
2. Disconnect all air hoses and electrical wiring
Tighten capscrews to standard torque.
leading from the right deck. Disconnect ground
strap between right deck and frame.
3. Attach a lifting device to the deck.
4. Remove the four (4) mounting capscrews (2,
Figure 2-4).
5. Remove deck from truck.
Inspect the rubber mounting pads for cracks, tears or

other damage. Replace with new if damaged.
FIGURE 2-4. RUBBER MOUNTING PADS (RIGHT

DECK)
1. Cover 5. Rubber Mounting
2. Capscrew 6. Bushing
3. Special Washer 7. Nut
4. Washer
B02011 9/97 Structural Components B2-3

CENTER DECK
Removal Installation
1. Disconnect the ground wire between the negative 1. Install deck on truck and align mounting holes and
terminal of the batteries and the frame. the rear rubber mounting studs.
2. Remove the three plugs, capscrews and nuts from 2. Tighten all mounting hardware. Install the covers
the front of the center deck. over the front access holes.
3. Remove the two nuts (2, Figure 2-5) and lock- 3. Connect the ground wire between the negative
washers from the two rear rubber mounts. terminal of the batteries and the frame.
4. Remove deck from truck.
FIGURE 2-5. REAR MOUNTING PADS FOR

CENTER DECK
1. Cover 3. Rubber Mounting
2. Nut 4. Capscrew Pad
B2-4 Structural Components B02011 9/97

DUMP BODY
Removal
1. Park truck on hard level surface and block all 2. Remove mud flaps from both sides of the truck.
wheels. Using special sling (561-98-61350) con- Pin rock ejectors in the up position.
nect cables and lifting device to the dump body
3. On each side of the dump body, remove the hoist
and take up slack as illustrated in Figure 3-1.
cylinder pin retainer capscrew and washer (4 and
5, Figure 3-2) from the dump body brackets (1).
Before raising or lifting body be sure there is Some means of supporting hoist cylinders will be
adequate clearance between body and overhead necessary prior to removing hoist cylinder pin.
structures or electric power lines.
4. Remove the top hoist cylinder pin (3, Figure 3-2)

from the dump body.
Be sure that lifting device is rated for at least a 35

ton capacity (31780 kg).
FIGURE 3-2. HOIST CYLINDER MOUNTING

FIGURE 3-1. DUMP BODY REMOVAL
1. Lifting Cables 2. Guide Rope 1. Body Brackets 4. Capscrew
2. Hoist Cylinder 5. Washer
3. Pin/Retainer Structure
B03015 Dump Body B3-1

5. Remove the capscrew and washer (2, Figure 3-3) Installation
securing the pivot pin (3). Remove the pivot pin
from each dump body pivot point. Pivot pin spac-
ers (4), will come out after pin is removed. Store 1. Attach lifting device to dump body and lower over
spacers in a manner so they will be installed in the truck frame. Align the dump body pivot with
the same location they were removed. frame mounting bracket.
6. Lift dump body clear of truck and move to storage 2. Install the spacers (4, Figure 3-3) as removed and
or work area. Place on blocks. body pivot pins (3) on each side of truck. If nec-
essary, adjust body to center it between the frame
7. Inspect bushings (6) in the body pivots for wear
rails. Refer to Figure 3-3.
or damage. Replace, if necessary.
NOTE: After installation, check to insure that the side

of the canopy and the side of the operators cab are in
alignment within 30mm (1.2 in). If necessary, adjust
body with shims at body pivot.
3. Secure pivot pin in place with capscrew and

washer (3, Figure 3-3). Tighten capscrews to
25-31.5 kg.m (181-228 ft.lbs.) torque.
4. If equipped, check engine exhaust tube in heated
body. Tube should be centered in body opening.
5. Align top eye of hoist cylinder and install hoist
cylinder pins. Secure pins with capscrews and
washers (4 and 5, Figure 3-2). Tighten capscrews
to 16-20 kg.m (116-145 ft.lbs.) torque.
6. Install mud flaps and release rock ejectors on
dump body.
FIGURE 3-3. BODY PIVOT PIN CROSS SECTION
1. Dump Body 4. Spacer

2. Capscrew & Washer 5. Frame Pivot Structure
3. Pivot Pin 6. Seal
7. Bushing
B3-2 Dump Body B03015

BODY PAD BODY PAD ADJUSTMENT (SIDE)
Removal With pads in place.

NOTE: It is not necessary to remove the dump body 1. Completely lower empty dump body until in con-
for replacing the body pads. Replace pads if worn tact with frame rail. Check all eight (8) pads to
excessively. insure full contact with frame. If not, adjust with
shims.
1. Raise dump body to sufficient height for removal
of body pads.
With pads removed.

1. Install a 55mm (2.16 in) spacer (1, Figure 3-5)
between the front of dump body and the frame.
Measure and record the distance between the
Place blocks between dump body and frame. Se- dump body and frame at four (4) locations on
cure blocks in place. each frame rail. Refer to Figure 3-5.
2. Subtract 35mm (1.38 in) from each dimension
2. Remove capscrews, lockwashers and rubber recorded above.
body pads with shims from body pad mounting 3. Raise body high enough to install pads and block
surface. Refer to Figure 3-4. in position to prevent body from lowering. Assem-
ble a shim pack for each pad as determined in
Installation Step 2 and install with capscrews, flatwashers,
1. Install new rubber body pads and shims. Install and nuts.
capscrews and lockwashers. 4. Remove blocking and spacer and lower body
completely.
5. Check all eight (8) pads to insure full contact with
frame. Adjust with shims if necessary.
FIGURE 3-4. BODY PAD AND GUIDE

FIGURE 3-5. BODY PAD ADJUSTMENT
1. Capscrew & Nut 5. Frame
2. Mounting Surface 6. Guide 1. 55mm (2.16 in) spacer 2. Body Pads
3. Shims a. Gap 1-2 mm
(4 locations)
4. Body Pad (0.040-0.080 in)

BODY PAD ADJUSTMENT (FRONT) BODY GUIDE
At time of body pad replacement, wear plates, which
NOTE: Adjust after lower body pads have been ad- the body guides contact, should be inspected for serv-
justed. iceability. Prior to checking the gap between the body
guides and wear plates, insure the body is centered on
the frame. The gap between the guides and wear
1. Total thickness of rubber pad (1, Figure 3-6) plates should be 1-2 mm (0.040-0.080 in.). Refer to
should be 50mm (2.0 in). Figure 3-4.
2. If not, adjust with shims (2). NOTE: Size of weld for body guide and wear plate is
0.31 inch (7.87 mm) unless otherwise specified. Use
AWS E 70 Series, Low Hydrogen Type Welding Rods,
such as E7016 or E7018.
BODY PIN
The body pin is located under the dump body at the

rear of the truck. This pin is intended to be used as a
safety to hold the body in the up position while the
technicians work under it.
Always store pin in body storage hole. Placement

of the pin in mainframe or matching body-up holes
located on the body can cause damage to frame or
body during dumping cycle.
Never work under a raised body unless body
FIGURE 3-6. FRONT BODY PAD safety pin is in the proper position to hold body up.
1. Pad 3. 50mm (2.0 in)

2. Shims 4. Capscrew

ROCK EJECTORS
Rock ejectors are placed between the rear dual wheels
to keep rocks or other material from lodging between
the dual tires. Failure to keep ejectors in working order
could allow debris to build up between the dual wheels
and cause damage to the tires. The rock ejectors can
be pinned up out of the way if desired.
Inspection
1. The ejectors must be positioned on the center line

between the rear tires within 0.25 in. (6.35 mm).
2. With the truck parked on a level surfact, the arm
structure should be approximately 4.88 in. (124
mm) away from the wheel spacer ring.
FIGURE 3-7 ROCK EJECTOR
NOTE: With Rock Ejector Arm (2, Figure 3-7) hang-
ing vertical, there must be NO GAP at stop on 1. Pin Structure 3. Cotter Pin
bracket (4). 2. Rock Ejector Arm 4. Rock Ejector Bracket
3. If the arm (2) becomes bent, it must be removed

and straightened.
4. The wear plates must be replaced if severely
worn.
5. Inspect the mounting brackets, pins (1) and stops
at each shift change for wear and/or damage, and
repair as necesary.

NOTES

FUEL TANK
The truck is equipped with a fuel tank mounted in front 2. Remove wire from tank sender if equipped with
of the rear tires on the right side. The tank is equipped fuel level indicator in instrument panel.
with an external fuel gauge and optional electric
3. Disconnect the fuel supply and return lines. Cap
sender for the instrument panel gauge.
all hoses and tank openings to prevent contami-
nation.
Removal
4. Connect a suitable lifting device to the tank and
1. Drain all fuel from tank to reduce weight to be
take up slack.
handled.
FIGURE 4-1. FUEL TANK INSTALLATION

1. Fuel Tank 9. Drain Cock 17. Nut 25. Straight Fitting
2. Fuel Gauge 10. Gasket 18. Washer 26. Return Hose
3. Gasket 11. Cover 19. Pipe Plug 27. Tapping Screw
4. Capscrew 12. Lockwasher 20. Breather Cap 28. Lockwasher
5. Lockwasher 13. Capscrew 21. Elbow Fitting 29. Collar
6. Filler Cap 14. Mounting Plate 22. Shutoff Valve 30. Bolt
7. Strainer 15. Mounting Plate 23. Nipple
8. Bushing 16. Bolt 24. Supply Hose
B04014 Fuel Tank B4-1

5. Loosen the bottom and top mount capscrews (16, If a tank has been damaged and requires structural
Figure 4-1) and take up slack on lifting device. repair, carry out such repairs before final cleaning. A
Remove capscrews and move tank to safe work- small amount of light oil should be sprayed into the tank
ing area. to prevent rust if the tank is to remain out of service.
All openings should be sealed for rust prevention.
6. Remove sending unit (2) and cover (11) on tank,
and other fittings as required to carry out interior
cleaning.
VENT
The fuel tank is vented through a small breather cap
Installation (20, Figure 4-1) installed in a port on the top of the tank.
1. Thoroughly clean the mounting areas on the This vent should be cleaned periodically and can be
frame and the tank. blown out with solvent. The vent must be free of caked
mud and debris that would cover the vent and prevent
2. Lift the fuel tank into position near the frame and proper fuel suction and return.
lower into position. Install capscrews (16), lock-
washers and nuts. Refer to Section “M” for information on various quick
fill systems, if equipped.
3. Tighten capscrews (16) evenly to 50-62 kg.m
(362-450 ft. lbs.) torque.
4. Connect fuel lines and fuel sender wire.
QUICK FUEL INSTALLATION (OPTION)
5. Close the tank drain cock, fill with fuel and check
for leaks. An optional quick fuelling system may be installed in
place of cover (11, Figure 4-1).
If a tank is to be weld repaired, special precautions

are necessary to prevent fire or explosion. Consult
local authorities if necessary, on safety regula-
tions before proceeding.
Cleaning
The fuel tank is provided with a drain and a cleaning
port in the side that allows steam or solvent to be
utilized in cleaning tanks that have accumulated for-
eign material.
It is not necessary to remove the tank from the truck
for cleaning of sediment, however rust and scale on
the walls and baffles may require complete tank re-
moval. This allows cleaning solutions to be in contact
with all interior surfaces by rotating the tank in various
positions, etc.
Prior to a cleaning procedure of this type, all vents, fuel
gauges, and hose connections should be removed and
temporarily sealed. After all scale, rust, and foreign
material have been removed, the temporary plugs can
be removed.
B4-2 Fuel Tank B04014

SECTION C
ENGINE, RADIATOR & AIR CLEANER
INDEX
COOLING SYSTEM
RADIATOR
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-1
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-3
BRAKE OIL COOLER
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-4
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-4
FAN
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-4
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-4
FAN BELT
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-5
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-5
ENGINE
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4-4
DRIVE LINE ADAPTER
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4-5
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4-6
Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4-7
AIR FILTRATION SYSTEM

AIR CLEANER
Service Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-1
Filter Element Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-1
MAIN FILTER ELEMENT
Main Filter Element Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-3
Air Intake Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-4
C01016 Index C1-1

NOTES
C1-2 Index C01016

COOLING SYSTEM
RADIATOR 3. Remove grille and steering oil cooler (2, Figure
3-1).
Engine cooling is accomplished by circulating the cool-
ant through the engine water jacket and the radiator. 4. Remove hood according to “Removal” instruc-
Air is pulled through the radiator core by an engine tions in Section “B”.
driven fan to remove heat from the circulating coolant. 5. If equipped with air conditioning, remove the
capscrews retaining the condenser core to the
Removal radiator and rotate the condenser core towards
1. Disconnect the negative and then the positive the left fender. Secure refrigerant lines and con-
battery cable. denser core away from radiator to prevent possi-
ble damage during radiator removal. If it is
necessary to remove the condenser from the
truck, refer to Section “M” and discharge the
refrigerant from the system, then remove the
condenser.
Before removing any cooling system components,

release cooling system pressure by turning radia-
tor cap counterclockwise to the first notch. Failure
to release pressure may result in hot coolant being
expelled causing serious injury.
Wear a face shield and protective gloves while
venting refrigerant from the air conditioning sys-
2. Position a container (completely clean if the cool- tem. Contact with the refrigerant will cause skin
ant is to be reused) under the drain cocks on the and tissue freezing (frostbite).
radiator and brake oil cooler. Be prepared to catch
as much as 256 l (67.6 gal.) of coolant. Open drain
cocks and allow coolant to drain completely. 6. Disconnect headlight wire (1, Figure 3-2) and air
horn hoses (2) on the left side of the radiator.
FIGURE 3-1. OIL COOLER FIGURE 3-2. WIRING AND HORN

1. Radiator 2. Steering Oil 1. Headlight Wiring 2. Air Horn Hoses
Cooler
C03018 Cooling System C3-1

10. Remove thermostat outlet hoses (2 & 3).
11. Disconnect de-aeration hose (4) and bypass hose
(5).
12. Remove radiator outlet hose (1, Figure 3-5) and
radiator bypass hose (2).
13. Remove torque converter oil cooler hoses (3 & 4).
FIGURE 3-3. RADIATOR HOOD

1. Radiator Hood 3. Radiator Support
2. Damper 4. Capscrews
7. Remove the three plugs, capscrews, and nuts

from across the top of the radiator hood that
secures it to the cross brace below.
8. Remove six (6) mounting capscrews (4, Figure
3-3) at the base of the radiator hood and remove.
Tag the shims for proper placement during as-
sembly.
9. Remove fan guard (1, Figure 3-4).
FIGURE 3-5. COOLANT AND OIL LINES

1. Outlet Hose 3. Torque Converter
2. Bypass Hose Hose
4. Torque Converter
FIGURE 3-4. RADIATOR COMPONENTS

1. Fan Guard 4. De-Aeration Hose
2. Thermostat Outlet Hose 5. Bypass Hose
3. Thermostat Outlet Hose
C3-2 Cooling System C03018

Service
Radiator service is a specialized function usually not
accomplished by most maintenance shops. The large
size and weight of the off-road truck radiators dictates
Radiator assembly weighs approximately 410 kg that a specialized radiator shop be used for service and
(904 lbs.) Use adequate lifting device. repair on the radiators.
14. Attach a sling or hoist to the radiator and take up
the slack. Remove radiator top mounting rod by
removing nuts (1, Figure 3-6).
Installation
15. Remove radiator bottom mount capscrews (4) and
remove radiator and torque converter oil cooler
assembly. Move radiator to a clean work area for 1. Inspect dampers (5, Figure 3-6) for cracks or
service. excessive stress. Replace as required.
2. Install radiator with torque converter oil cooler
assembly with radiator bottom mount capscrews
(4) .
3. Install radiator top mounting rod with nuts (1).
Tighten nuts on each end of tie rod and center the
rods between the brackets to position the radiator
so that the fan blades are centered in the shroud.
4. Install torque converter oil cooler hoses (3&4,
Figure 3-5).
5. Install radiator outlet hose (1) and radiator bypass
hose (2).
6. Connect de-aeration hose (4, Figure 3-4) and
bypass hose (5).
7. Install thermostat outlet hoses (2&3).
8. Install fan guard (1).
9. Install six mounting capscrews (4, Figure 3-3) at
the base of the radiator hood and remove.
10. Install the three plugs, capscrews, and nuts from
across the top of the radiator hood that secures it
to the cross brace below.
11. Connect headlight wire (1, Figure 3-2) and air horn
hoses (2) on the left side of the radiator.
12. If equipped with air conditioning, install the con-
denser core to the radiator. Refer to Section “M”
to evacuate and recharge the system.
13. Install hood according to “Installation” instructions
in Section “B”.
FIGURE 3-6. RADIATOR MOUNTING 14. Install oil cooler (2, Figure 3-1) and radiator grille.
1. Nut 5. Damper 15. Make sure all coolant drains are closed and all
2. Washer 6. Washers hoses installed. Service cooling system with the
3. Rubber Mount 7. Radiator Support proper mixture of antifreeze as recommended in
4. Capscrews & 8. Capscrews the Lubrication and Service Section. Check for
Lockwashers static leakage and correct any leaks.

16. Install the battery cables as follows: 4. Attach a suitable lifting device to the brake oil
a. Install the battery positive cable first. cooler and remove mounting bolts from brackets
at right and left sides of the cooler. Lower cooler
b. Install the negative cable next.
from truck.
17. Start engine and run until cooling system reaches
operating temperature, recheck the cooling sys- Installation
tem for leakage during engine operation.
1. Lift cooler up in place and secure with mounting
capscrews.
2. Connect brake cooling oil lines and water coolant
lines to cooler.
If air is not completely bled from cooling system 3. Fill radiator and brake cooling oil tank to proper
during refill, additional coolant may be required levels with proper fluids as specified in Section
due to air entrapped which will gradually dissipate "P", "Lubrication and Service".
as the engine comes up to temperature. Refill
radiator as required before putting machine to FAN
work.
Removal
BRAKE OIL COOLER 1. Remove radiator, hood, grill, and water piping as
specified in Section “B” or earlier in this section.
Removal
2. The fan guard may be separated and removed or
1. Drain engine coolant and the brake cooling oil. can be moved back toward the engine clear of the
2. Disconnect the two cooling water hoses (1, 2, fan hub.
Figure 3-7) from the right side of the brake cooler. 3. Remove capscrews and lockwashers and lift fan
3. Disconnect the brake oil cooling lines (3, 5) from and spacer from pulley hub.
the brake oil cooler.
Bent or cracked fan blades cannot be repaired. The

fan must be replaced. Do not attempt to repair
The brake oil cooler weighs 247 kgs (545 lbs). Use damaged blades.
a suitable lifting device that can safely handle 247
kgs (545 lbs). Installation
1. Inspect fan carefully before installation. If blades
are bent or cracks are evident, install a new fan.
2. Clean mounting surfaces thoroughly and install
spacer on fan hub.
3. Lift fan into position and install over pilot diameter
of hub.
4. Install the capscrews and lockwashers and torque
to standard torque. Use alternating pattern and
increasing levels of torque until all capscrews are
evenly torqued.
5. Install fan guard around fan if separated during
removal.
FIGURE 3-7. BRAKE OIL COOLER 6. Install radiator, hood, grille and water piping as
1. Water Outlet Hose 4. Brake Oil Cooler specified in Section “B” or earlier in this section.
2. Water Inlet Hose 5. Oil Outlet Tube 7. Refill with coolant.
3. Oil Inlet Tube

FAN BELT Installation
The Poly-Vee type belt can be changed by removing 1. Work the belt around fan blades and into the area
the fan guard without dismantling or removing the fan of the pulleys.
from the engine. Care must be exercised in doing this 2. With a long one inch drive wrench, have one
however as the belt will be a tight fit around edge of person rotate the belt tensioner clockwise until
blades and sheet metal of shroud. the belt can be installed over the grooves of both
pulleys. Make sure the belt is on the correspond-
Removal ing grooves of both pulleys and slowly release the
The belt tension is automatically maintained by spring belt tensioner pulley against the belt.
pressure to the idler pulley. Manual adjustment is not
necessary.
1. Poly-Vee belt removal will require 2 people. With
a long handled one inch drive wrench, turn the
tension hub clockwise against spring pressure to
release tension on the fan belt. This will take
considerable effort against the spring pressure.
Refer to Figure 3-8.
2. Remove belt from pulleys and work around fan to
remove from truck. Note that considerable spring
tension is involved and it must be released care-
fully until the tensioner pulley is fully released
counter clockwise.
FIGURE 3-8. FAN BELT REMOVAL

NOTES

ENGINE
ENGINE
The Model 330M truck is equipped with a Komatsu
SA12V140Z-1 turbocharged diesel engine. Engine
power is transmitted to the TORQFLOW transmission
by a drive line adapter with damper assembly, and a
drive shaft with two universal joints.
Removal
1. Position the truck in work area with adequate
overhead clearance to permit raising the dump
body.
2. Apply parking brake and block wheels to prevent
truck movement. Raise body and install safety
pin.
FIGURE 4-2. PIPES AND WIRING

Do not work under raised body without first mak- 1. Water Pipes 3. Hose
ing sure the safety pin is securely installed. 2. Ground Terminal 4. Alternator Wire
3. Close the fuel supply valve. NOTE: Prior to disassembly or removal, tag or mark
4. Remove grille according to procedure in Section all air lines, oil lines, fuel lines and electrical connec-
“B”. Remove radiator according to “Radiator Re- tions to assure correct assembly at time of engine
moval” procedure in this section. installation. Plug all ports and cover all hose fittings or
connections when disconnected to prevent dirt or for-
5. Disconnect the negative, then the positive battery eign material from entering.
cables. Disconnect the electrical lead from the
7. Disconnect water pump pipes (1, Figure 4-2) and
battery charging alternator.
hose (3).
6. Disconnect by-pass filter hoses (3, Figure 4-1)
8. Disconnect ground terminal (2) and alternator wire
and fuel filter hoses (4).
(4).
9. Disconnect starter motor wiring (1, Figure 4-3) and
ground terminals (2).
FIGURE 4-1. OIL LINES

FIGURE 4-3. STARTING MOTOR
1. By-pass Filter 3. By-pass Filter Hose
2. Fuel Filter 4. Fuel Filter Hose 1. Starter Motor 2. Ground Terminals
Wiring
C04019 11/98 Engine C4-1

FIGURE 4-4. ENGINE HOSES AND WIRING FIGURE 4-6. INTAKE AND EXHAUST PIPING
1. Priming Hose 1. Intake Pipes 2. Exhaust Pipes

4. Shut-off Valve
2. Return Hose Wiring
3. Engine Control Cable 5. Air Hose
10. Disconnect priming hose (1, Figure 4-4), return

13. Remove intake pipes (1, Figure 4-6), and exhaust
hose (2), engine control cable (3), and shut-off
pipes (2).
valve wiring (4).
14. Remove cover (1, Figure 4-7).
11. Disconnect air hose (5), and temperature sensor
wire (6).
12. Disconnect water temperature sensor connector
(1, Figure 4-5), heater hose (2), and hoses (3).
FIGURE 4-7. COVER

1. Cover
FIGURE 4-5. ENGINE HOSES AND WIRING
1. Sensor Connector 3. Hoses
2. Heater Hose
C4-2 Engine C04019 11/98

FIGURE 4-8. ENGINE WIRING AND LINES FIGURE 4-10. OIL LINES
1. Air Compressor Tube 3. RPM Sensor 1. Brake Cooling Hose 2. Tubes
2. Switch Wire Wiring
17. Remove brake cooling hose (1, Figure 4-10), and

tubes (2).
15. Disconnect air compressor tube (1, Figure 4-8), 18. Remove drive shaft guard (1, Figure 4-11), and
engine oil temperature switch wire (2), and RPM drive shaft (2).
sensor wiring (3).
16. Disconnect engine ground terminals (1, Figure
4-9).
The complete engine module weighs approxi-
mately 3,200 kgs (7,050 lbs.). Make sure sling,
hoist, and spreader bar is of adequate capacity.
During engine removal, insure that engine removal
path is clear of personnel and equipment.
19. Attach lifting device to engine and remove from

frame. Move engine to a clean work area and
mount on work stands or cribbing.
FIGURE 4-9. GROUND CONNECTIONS
1. Engine Ground Terminal
FIGURE 4-11. DRIVE SHAFT

1. Drive Shaft Guard 2. Drive Shaft
C04019 11/98 Engine C4-3

Installation
10. Connect priming hose (1, Figure 4-4), return hose
(2), engine control cable (3), and shut-off valve
wiring (4).
The complete engine module weighs approxi- 11. Connect starter motor wiring (1, Figure 4-3) and
mately 3,200 kgs (7,050 lbs.). Make sure sling, ground terminals (2).
hoist, and spreader bar is of adequate capacity. 12. Connect ground terminal (2) and alternator wire
During engine removal, insure that engine removal (4).
path is clear of personnel and equipment.
13. Connect water pump pipes (1, Figure 4-2) and
hose (3).
1. Attach lifting device to engine and install in frame.
Tighten engine mounting capscrews to 56 ±6 14. Connect by-pass filter hoses (1, Figure 4-1).
kg.m (405±43 ft.lbs.) 15. Connect the negative, then the positive battery
NOTE: Refer to the procedure for centering the engine cables. Connect the electrical lead from the bat-
assembly and transmission assembly in Section tery charging alternator.
"F","Transmission Installation". 16. Refer to “Radiator Installation” procedure, this
section and install the radiator. Install grille ac-
2. Install drive shaft guard (1, Figure 4-11), and drive cording to procedure in Section “B”.
shaft (2). Apply a thread tightener (Three Bond 17. Open the fuel supply valve.
#1374) to capscrews. Tighten capscrews to 18 ±2
18. Adjust throttle cables per instructions in “Engine
kg.m (130 ±14 ft.lbs.) torque.
Components”, this Section.
3. Install brake cooling hose (1, Figure 4-10), and
19. Recheck engine to be assured all air, oil, electric,
tubes (2).
and fuel lines have been reconnected to the
4. Connect engine ground terminals (1, Figure 4-9). proper locations and that all connections are se-
cure.
5. Connect air compressor tube (1, Figure 4-8),
engine oil temperature switch wire (2), and RPM NOTE: Refer to Section "P", Lubrication and Service
sensor wiring (3). for the proper fluids.
6. Install cover (1, Figure 4-7).
20. Fill engine oil to the specified level. Refill radiator
7. Install intake pipes (1, Figure 4-6), and exhaust
with coolant to the specified level and run the
pipes (2).
engine to circulate the oil and coolant through the
8. Connect water temperature sensor connector (1, system until temperatures are stabilized. Then
Figure 4-5), heater hose (2), and hoses (3). check fluid levels again. Check for oil, fuel or
coolant leakage.
9. Connect air hose (5), and temperature sensor wire
(6).
C4-4 Engine C04019 11/98

Drive Line Adapter
If a new, or replacement engine, is to be installed, it 7. Remove bearing (1, Figure 4-15) for cleaning,
may be necessary to remove and install the drive line inspection, and fresh lubrication, or replacement,
adapter. if necessary.
Drive Line Adapter Removal

overhead clearance to permit raising the dump
body.
Do not work under raised body without first mak-

ing sure the safety pin is securely installed.
pin. FIGURE 4-13. OUT PUT SHAFT
3. Remove drive shaft guard (1, Figure 4-11). Re- 1. Snap Ring 2. Damper Cover
move capscrews (5, Figure 4-12) from cross and 3. Capscrew
bearing assembly (2) at both ends of drive shaft,
and then remove drive shaft assembly (1).
4. Remove output drive flange (6). Remove cap-
screws (7) and bearing cover (3).
5. Remove snap ring (1, Figure 4-13). Remove re-
taining capscrews (3) around damper cover (2),
and then with sling, eye bolts, and guide bolts,
remove damper cover (2).
6. Remove capscrews holding damper assembly to
flywheel (12, Figure 4-16). Attach a sling and
lifting device and remove output shaft damper
assembly (1, Figure 4-14).
FIGURE 4-14. OUTPUT SHAFT DAMPER ASSEMBLY
1. Output Shaft Damper Assembly 2. Housing

1. Drive Shaft 4. Damper Cover
2. Cross & Bearing Assy. 5. Capscrews FIGURE 4-15. PILOT BEARING
3. Bearing Cover 6. Output Drive Flange 1. Bearing 2. Flywheel
7. Capscrews
C04019 11/98 Engine C4-5

Drive Line Adapter Installation
overhead clearance to raise the dump body.
Do not work under raised body without first mak-

ing sure the safety pin is securely installed.
pin.
3. Refer to "Drive Line Adapter Damper Assembly"
for assembly of the adapter, if this was disassem-
bled.
4. If removed, use a push tool, and press fit bearing
(1, Figure 4-15 / 9, Figure 4-16) into flywheel.
Bearing must be packed and roller surface lubri-
cated with Komatsu lubricant, 427-12-11871, for
long life. Refer to "Recommended Lubricants"
later in this section.
5. Apply thread tightener (Three Bond #1374) to
FIGURE 4-16. ADAPTER CROSS SECTION
capscrews (12, Figure 4-16) and install output
1. Oil Seal 7. Rubber
shaft damper assembly (1, Figure 4-14) to fly-
2. Bearing 8. Outer Body
wheel. Tighten capscrews (12, Figure 4-16) to
3. Output Shaft 9. Pilot Bearing
11.5 ± 1 kg.m (83 ± 7 ft lbs) torque. 4. (not shown) Damper Assembly 10.Capscrew
6. Use eye bolts and guide bolts to install damper (includes 3*, 5*, 6*, 7*, & 8*) 11. Capscrew
cover (2, Figure 4-13). Apply thread tightener to 5. Flange 12. Capscrew
capscrews and tighten capscrews (3, Figure 4-13 6. Inner Body 13. Capscrew
/13, Figure 4-16) to 3.2 kg.m (23 ft lbs) torque.
NOTE: Do not over pack fill points. Forcing too
7. Bearing (2, Figure 4-16 / 13, Figure 4-18) must be much grease into cavities could displace seals.
packed with Komatsu lubricant, 427-12-11871.
(Refer to "Recommended Lubricants" and Figure
4-17 for packing bearing and cavity with grease.)
If removed, press fit bearing (13, Figure 4-18) in
cover (11). Install retaining ring (14).
8. Apply thread tightener to capscrews (18) and
install bearing cover (15). Tighten capscrews to
11.5 ± 1 kg.m (83 ± 7 ft lbs) torque.
9. Install oil seal (19) into bearing cover (15). Push
drive flange onto output shaft (3, Figure 4-16).
10. Attach a sling and lifting device and move drive
shaft assembly (1, Figure 4-12) [without cross and
bearing assembly (2)] into position.
11. Install cross and bearing assembly (2) between
drive shaft and flange at both ends of drive shaft
with capscrews (5). Tighten all cross and bearing
capscrews (5) to 28 kg.m (202 ft lbs) torque.
12. Install drive shaft guard (1, Figure 4-11). FIGURE 4-17. PACKING BEARING AND CAVITY
C4-6 Engine C04019 11/98

Drive Line Adapter Damper Disassembly
1. Remove oil seal (19, Figure 4-18) from bearing 4. Disassemble output shaft damper assembly as
cover (15), if not previously removed. follows.
2. Remove bearing (13) from damper cover (11), if a. Match mark positions of flanges (6A/B), inner
not previously removed. body/shaft (10), and outer body (8), before
disassembling.
3. Do not remove output shaft from damper assem-
b. Remove flanges (6A/B), inner body/shaft (10),
bly (4). The inner body/output shaft assembly (10)
and rubber dampers (9) from outer body (8).
is provided as a one-piece part. No effort should
be made to separate the pieces. If shaft appears 5. If not previously removed, remove bearing (2)
loose in inner body, replace this assembly. from flywheel for cleaning, inspection, and fresh
lubrication, or replacement, if necessary.
NOTE: To keep the balance when reassembling, mark
the set positions of flanges (6A/6B), outer body (8), and
inner body/shaft (10) before disassembling.
FIGURE 4-18. DRIVE LINE ADAPTER

1. Flywheel Housing 8. Outer Body 15. Bearing Cover
2. Pilot Bearing 9. Rubber Damper (large) 16. Breather
3. Capscrew & Washer 9A. Rubber Damper (small) 17. Plug
4. Damper Assembly 10. Inner Body/Output Shaft 18. Capscrew & Washer
5. Capscrew & Washer 11. Cover 19. Oil Seal
6A. Flange 12. Capscrew & Washer 20. Output Drive Flange
6B. Flange 13. Bearing 21. Cap Plate
7. Dowel Pin 14. Retaining Ring 22. Retaining Ring
C04019 11/98 Engine C4-7

Drive Line Adapter Damper Assembly 6. Apply adhesive (Three Bond #1104) on flange
(6B, Figure 4-18) and install according to balance
1. Replace any worn or damaged parts.
lines that were made during disassembly.
2. Coat mating surface of outer body (8, Figure 4-18)
7. Align the balance lines of the outer body, inner
and mating surface side of flange (6A) with adhe-
body, and flange, then assemble.
sive (Three Bond #1104), then assemble accord-
ing to balance lines that were made during 8. Apply a thread tightener (Three Bond #1374) on
disassembly. Apply a thread tightener (Three flange mounting bolts (5) and tighten to 18 ±2
Bond #1374) on flange mounting bolts (5) and kg.m (130 ±15 ft.lbs.) torque.
tighten to 18 ±2 kg.m (130 ±15 ft.lbs.) torque.
9. Refer to "Drive Line Adapter Installation, steps 4
3. Install inner body/output shaft (10) according to through 12", for remaining installation of all other
balance lines that were made during disassem- related parts, and driveline.
bly.
4. Coat outer body (8), inner body/shaft (10), and RECOMMENDED LUBRICANTS
rubber dampers (9) with LW008-27 grease. Refer The instructions listed in these pages contain refer-
to "Recommended Lubricants". ences to lubricants that are used in Haulpak manufac-
5. After assembling rubber dampers (2 & 5, Figure turing and assembly processes. These lubricants may
4-19), fill the space (3, shaded portion) uniformly be identified and obtained as follows:
with LW008-27 grease. Refer to "Recommended NOTE: "Approved source" indicates the material prop-
Lubricants". erties have been approved for Haulpak manufacturing.
This is not a commercial endorsement for the product.
The rubber damper area requires LW008-27,
Multi-Purpose NLGI #2 grease. This is a multi-
NOTE: Do not over pack fill space. Forcing too purpose extreme pressure lubricating grease,
much grease into cavities could displace rubber consisting of a lithium complex soap base and
dampers. mineral oil.
Approved source:
Mobilgrease HP, from Mobil Oil Corp.
The bearings are to be packed with LW030-27.
The present source for this lube, is Komatsu
Parts Distribution, part number 427-12-11871,
which is a one gallon container.
This amount is enough for two installations.
Recommended Lubricants & Sealants

A Komatsu Lubricant 1 gallon Can -
(427-12-11871) Order from Haulpak
B LW008-27 grease. Mobil Grease HP
3 Tubes*
C Thread Tightener Three Bond #1374*
D Liquid Gasket Three Bond USA-
LW067-78 grade #1104*
FIGURE 4-19. * - Obtain locally

1. Outer Body Member 4. Inner Body Member
2. Large Rubber Damper 5. Small Rubber NOTE: Refer to Section "P", Lubrication and Service,
3. Grease Area Damper for periodic inspections of this drive area.
C4-8 Engine C04019 11/98

AIR FILTRATION SYSTEM
AIR CLEANER Filter Element Replacement

Air used by the diesel engine passes through the air
cleaner assembly mounted on the right side deck of
the truck. This dry type air cleaner filters particles as air
passes through the filter elements. The truck engine MUST NEVER be operated with
elements removed. Engine operation with filter
Service Checks elements removed can cause serious engine dam-
age. Run the engine ONLY with the air cleaner
assembly completely assembled and closed.
Main filter element restriction is registered by a service

indicator located above the air filter assembly. As filter
The truck engine must be shut down before serv- becomes clogged with dirt, a vacuum differential is
icing the air cleaner assembly or opening the en- created by engine demand for air causing indicator
gine air intake system. float to expose red area. Filter service is needed when
red area is exposed.
1. Inspect and empty air cleaner dust collector at 1. Shut engine down. Clean area around filter ele-
regular intervals. Daily inspections are recom- ment cover and remove outer wing nut (3, Figure
mended. 5-1) and cover
2. Before operation or after the engine has been shut 2. Loosen inner wing nut (3) on air cleaner to free
down, observe the air cleaner service vacuum main element assembly. Pull main element clear
indicator which is located above the air filter as- of assembly.
sembly. Filter service is required when the indica-
3. Inspect filter element carefully for possible dam-
tor shows maximum restriction (RED).
age, holes, breaks, etc., which might affect reuse
3. Make certain that the air inlet on the air cleaner is of element. If element appears serviceable other
free of obstruction. Inlet must not be clogged or than being dirty, proceed with the cleaning proce-
damaged. dure. If defects are found, discard element.
4. Check engine air intake tube, hoses and clamps.
All connections and joints must be air tight to
prevent entrance of dirty air.
5. Air cleaner housing fasteners and mountings must
be tight.
6. After filter service has been accomplished, reset
air cleaner service vacuum indicator by pushing
Have a new safety (secondary) filter element at
the reset button on top of indicator.
hand before removing old one. Do not keep intake
system open to atmosphere any longer than abso-
lutely necessary.
C05010 12/91 Air Filtration System C5-1

FIGURE 5-1. AIR CLEANER ASSEMBLY
1. Air Intake Cover 4. Primary Filter Element

2. Safety Filter Element Nut 5. Safety Filter Element
3. Outer and Inner Wing Nuts
C5-2 Air Filtration System C05010 12/91

4. Install new safety element and secure with wing b. Rinse element with a stream of fresh water in
nut. Tighten wing nut to 10 ft. lbs. (13 N.m) the opposite direction of normal air flow until
torque. rinse water runs clear. Maximum permissible
water pressure is 40 psi (276 kPa). A complete,
5. Install clean or new main filter element into air
thorough rinse is essential.
cleaner and secure with wingnut. Tighten wing nut
hand tight, do not use a wrench or pliers. If filter c. Dry the element thoroughly. If drying is done
element is being reused, make sure sealing gas- with heated air, the maximum temperature
o o
ket is not damaged, the gasket must seal com- must not exceed 140 F (60 C) and must be
pletely. circulated continually. Do not use a light bulb
for drying elements.
6. Install cover and tighten outer wing nut.
d. When the element is thoroughly clean, inspect
7. Close and latch the dust collector on the bottom carefully for even the slightest ruptures or punc-
of air cleaner assembly. tures and for damaged gaskets. A good
method to detect ruptures in the paper filter
material is to hold a light inside filter element as
shown in Figure 5-2 and inspect outer surface
of element, any holes or ruptures will be easily
spotted. If holes or ruptures are found, do not
reuse the element, discard and install a new
unit.
2. Clean dust loaded elements with dry, filtered,
compressed air:
a. Maximum nozzle pressure must not exceed 30
psi (207 kPa). Nozzle distance from filter ele-
ment surface must be at least one inch (25 mm)
to prevent damage to the filter material.
FIGURE 5-2. INSPECTING FILTER ELEMENT b. As shown in Figure 5-3, direct stream of air from
nozzle against inside of filter element. This is the
clean air side of the element and air flow should
Main Filter Element Cleaning be opposite of normal air flow.
NOTE: Remember that only the main (primary) filter
element may be cleaned, and then only if it is structur-
ally intact. Do not reuse any element which is dam-
aged. DO NOT clean and reuse the safety (secondary)
filter element. Replace this item when clogged or
damaged .
After inspection, determine if the element should be
cleaned by using either washing or compressed air
methods. If element is clogged with dust, compressed
air will clean element. If element is clogged with carbon,
soot, oil and/or dust, the complete washing procedure
will produce the best results.
1. Wash elements with water and detergent as fol-
lows:
a. Soak the element in a solution of detergent and
water for at least 15 minutes. Rotate element
back and forth in the solution to loosen dirt
FIGURE 5-3. CLEANING FILTER ELEMENT WITH
deposits. DO NOT soak elements for more than COMPRESSED AIR
24 hours.
C05010 12/91 Air Filtration System C5-3

c. Move air flow up and down vertically with pleats
in filter material while slowly rotating filter ele-
ment.
d. When cleaning is complete, inspect filter ele-
ment as shown in Figure 5-2 and if holes or
ruptures are noted, replace the element with a
new item.
Air Intake Troubleshooting

To insure maximum engine protection, be sure that all
connections between air cleaner and engine intake are
tight and positively sealed. If air leaks are suspected,
check the following:
1. All intake lines, tubes and hump hoses for breaks,
cracks, holes, etc., which could allow an intake air
leak.
2. Check all air cleaner gaskets for positive sealing.
3. Check air cleaner elements, main and safety, for
ruptures, holes or cracks.
4. Check air cleaner assembly for structural damage,
cracks, breaks or other defects which could allow
air leakage. Check all mounting hardware for
tightness.
C5-4 Air Filtration System C05010 12/91

SECTION D
ELECTRICAL SYSTEM
INDEX
24VDC ELECTRICAL SUPPLY SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . D2-1
ELECTRICAL SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . D2-1
BATTERY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-1
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-1
Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-1
Maintenance and Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . D2-2
Spillage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-3
BATTERY CHARGING ALTERNATOR . . . . . . . . . . . . . . . . . . . . . . . . . D2-3
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-4
ENGINE PRELUB SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-5
Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-5
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-5
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-7
24VDC ELECTRICAL SYSTEM COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . D3-1

VEHICLE MONITOR SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-1
Vehicle Monitor Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-4
Sensors, Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-4
MONITOR PANEL DISPLAYS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-6
INSTRUMENT PANEL INDICATORS, TEST SWITCH . . . . . . . . . . . . . . . . . D3-10
ELECTRONIC ACCELERATOR PEDAL SYSTEM . . . . . . . . . . . . . . . . . . . D3-12
AISS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-13
TRANSMISSION CONTROLLER . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-14
EXHAUST BRAKE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-16
POINTS TO REMEMBER WHEN TROUBLESHOOTING . . . . . . . . . . . . . . . . . . D4-1

POINTS TO REMEMBER WHEN CARRYING OUT MAINTENANCE . . . . . . . . . . . . D4-2
Points to remember when handling electric equipment . . . . . . . . . . . . . . . . . . D4-2
Handling of controller boxes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-7
Precautions when performing arc welding on the truck . . . . . . . . . . . . . . . . . . D4-7
Points to remember when troubleshooting electric circuits . . . . . . . . . . . . . . . . D4-7
Points to remember when handling hydraulic equipment
CHECKS BEFORE TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . D4-10
TYPE OF CONNECTOR AND POSITION OF INSTALLATION . . . . . . . . . . . . . . D4-12
FOR ARSC (AUTOMATIC RETARDER SPEED CONTROL) . . . . . . . . . . . . . . . D4-17
CONNECTOR PIN ALLOCATION CHART . . . . . . . . . . . . . . . . . . . . . . . . . D4-18
CONNECTION TABLE FOR CONNECTOR PIN NUMBERS . . . . . . . . . . . . . . . . D4-23
EXPLANATIONS OF FUNCTIONS (CONTROL MECHANISM) OF ELECTRICAL SYSTEM D4-33
Explanation of functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-33
Explanation of self-diagnostic display functions . . . . . . . . . . . . . . . . . . . . D4-33
Checking operation of electrical system . . . . . . . . . . . . . . . . . . . . . . . . D4-35
D01021 Index D1-1

MONITOR PANEL ACTION CODES AND SERVICE MODE . . . . . . . . . . . . . . . . D4-39
Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-39
Action code display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-39
Service mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-40
Method of deleting trouble data from memory . . . . . . . . . . . . . . . . . . . . . . D4-48
Precautions when operating service mode . . . . . . . . . . . . . . . . . . . . . . . D4-48
Table 1 bit numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-51
Brake air pressure sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-52
SELF-DIAGNOSTIC DISPLAY METHOD FOR MONITOR PANEL AND CONTROLLERS . D4-53
Monitor panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-53
Transmission controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-53
Self -diagnostic display code table . . . . . . . . . . . . . . . . . . . . . . . . . D4-53
Warning display table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-54
Method of re-enacting fault displayed . . . . . . . . . . . . . . . . . . . . . . . . D4-55
Operation of controller when fault is detected . . . . . . . . . . . . . . . . . . . . D4-55
Transmission mode display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-56
Saving self-diagnostic display to memory . . . . . . . . . . . . . . . . . . . . . . . . D4-56
Saving service code to memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-57
TABLE OF SERVICE CODES AND ACTION CODES
Table of service codes and action codes related to monitor panel . . . . . . . . . . . D4-58
Table of service codes and action codes related to transmission controller . . . . . . . D4-59
Table of service codes and action codes related to suspension controller . . . . . . . D4-62
Table of service codes and action codes related to PMC . . . . . . . . . . . . . . . . D4-63
METHOD OF USING TABLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-64
METHOD OF USING TOUBLESHOOTING CHARTS . . . . . . . . . . . . . . . . . . . D4-65
Method of using troubleshooting chart for each troubleshooting fault . . . . . . . . . . D4-65
ADJUSTING ELECTRONIC MONITOR (Speedometer, module) . . . . . . . . . . . . . . D4-67
SETTING ROTARY SWITCH (Model and network data) when replacing trans. controller . D4-68
METHOD OF DELETING DATA FROM TRANS. CONTROLLER MEMORY . . . . . . . . D4-69
TRANSMISSION SHIFT CONTROLLER SYSTEM TROUBLESHOOTING . . . . . . . . . . D5-1

TROUBLESHOOTING CHARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D5-1
Troubleshooting Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D5-1
MONITOR PANEL TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . D6-1

TROUBLESHOOTING CHARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-1
ENGINE ELECTRONIC DIAGNOSTIC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . D7-1

Fault Code Information (T01-001) . . . . . . . . . . . . . . . . . . . . . . . . . . . D7-4
ELECTRICAL SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D7-6
HYDRAULIC & MECHANICAL SYSTEMS TROUBLESHOOTING . . . . . . . . . . . . . . D8-1

D1-2 Index D01021

24VDC ELECTRIC SUPPLY SYSTEM
ELECTRICAL SYSTEM DESCRIPTION Service
Four (4) 12 volt storage batteries are located on the All batteries must be maintained periodically, espe-
right hand deck and are wired in a series and parrallel cially machines equipped with electric starters.
combination to provide 24VDC for the Truck electrical The electrolyte level of each cell should be checked at
system and components. the interval specified in the Lubrication and Service
When the engine is shut down and keyswitch is "Off", Section “P”, and water added if necessary. The proper
24 volts is supplied to the circuits for the alternator, level to maintain is 3⁄8– 1⁄2 in. (10-13 mm) above the
keyswitch, and the hazard flasher. plates. To insure maximum battery life, use only dis-
tilled water or water recommended by the battery
With engine running and keyswitch "On", all circuits manufacturer. After adding water in freezing weather,
are capable of operating under the necessary condi- operate the engine for at least 30 minutes to thoroughly
tions for the circuit. Whether a particular circuit is mix the electrolyte.
activated depends on components in circuit and pur-
pose.
The electric system is made up of many circuits that
warn, illuminate, start, control, and monitor the truck
electric components during operation. DO NOT SMOKE or allow flame around a dead
Refer to the Electrical Schematic, Section "R", for battery or during the recharging operation. The
specific circuit details. expelled gas from a dead cell is extremely explo-
sive.
Excessive consumption of water indicates leakage or

overcharging. Normal water usage for a unit operating
Before welding on truck, be certain that each of eight hours per day is about one to two ounces per cell
these components are completely disconnected: per month. For heavy duty operation (24 hour) normal
consumption should run about one to two ounces per
• Transmission Controller cell per week. Any appreciable increase over these
• Batteries figures should be considered a danger signal.
• Battery Charging Alternator
Storage
BATTERY Idle batteries should not be allowed to stand unat-
The four (4) 12 volt storage batteries are of the lead- tended. If equipment is to stand unused for more than
acid type, each containing six 2-volt cells. During two weeks, the batteries should be removed and
operation, the storage batteries function as an electro- placed in a cool, dry place where they may be checked
chemical device for converting chemical energy into periodically and charged when necessary.
the electrical energy required for operating the acces-
All batteries will self discharge over a period of time if
sories when the engine is shut down.
not used and charged. A fully charged battery will lose
25% of its power in as little as 30 days in warm
weather. A 50% power loss will occur in 60 days. This
self discharge takes place even though the battery is
not connected in a circuit and is more pronounced in
Lead-acid storage batteries contain sulphuric warm weather than in cold.
acid, which if handled improperly may cause seri- The rate of self-discharge of a battery kept at 100°F
ous burns on skin or other serious injuries to (38°C) is about six times that of a battery kept at 50°F
personnel. Wear protective gloves, aprons and eye (19°C) and self-discharge of a battery kept at 80°F
protection when handling and servicing lead–acid (27°C) is about four times that one at 50°F (10°C).
storage batteries.
See the precautions in Section “A” of this manual Over a thirty day period, the average self-discharge
to insure proper handling of batteries and treat- runs about 0.002 specific gravity per day at 80°F
ment for accidents involving sulphuric acid. (27°C).
D02020 24VDC Electric Supply System D2-1

Some possible causes for an undercharged battery
Specific Gravity Freezing Temperature are:
Corrected to 80°F (27°C) Degrees
Sulfated battery plates
1.280 -90°F (-70°C)
Loose battery connections
1.250 -60°F (-54°C)
Defective wire in electrical system
1.200 -16°F (-27°C)
Loose alternator drive belt
1.150 +5°F (-15°C)
A defective alternator
1.100 +19°F (-7°C)
Overcharging, which causes overheating, is first indi-
cated by excessive use of water. If allowed to continue,
To offset the results of self-discharge, idle batteries cell covers will push up at the positive ends and in
should receive a booster charge (not a quick charge) extreme cases the battery container will become dis-
at least once every thirty days. Batteries allowed to torted and cracked.
stand for long periods in a discharged condition are
attacked by a crystallization of the lead sulfate on the A battery can discharge if it is not clean and dry. A fully
plates. Such batteries are called sulfated and are, in charged battery can become discharged to a level low
the majority of cases, irreparably damaged. In less enough to prevent it from starting an engine in as little
severe cases, the sulfated battery may be restored to time as one week. The problem may be acid film and
limited service by prolonged charging at a low rate dirt lying on top of the battery. This creates a path for
(approximately 1⁄2 normal rate). electricity to travel between the terminals, thus dis-
charging the battery.
An undercharged battery is extremely susceptible to
freezing when allowed to stand in cold weather. Use either an analog or digital voltmeter to determine
if there is a path between the terminals.
The electrolyte of a battery in various stages of charge
will start to freeze at temperatures indicated in the a. Set the voltmeter at a range to indicate battery
tableabove. voltage.
The temperatures in the table indicate the points at b. Place the positive lead of the voltmeter on the
which the first ice crystals appear. Lower temperatures positive battery post.
must be reached for a solid freeze. Solid freezing of c. Place the negative lead so that it touches the
the electrolyte may crack the battery case and damage battery case approximately one inch away from
the positive plates. As will be noted, a 3⁄4 charged the positive post.
battery is in no danger of freezing, therefore, a 3⁄4
d. The voltmeter should indicate 0.0 volts. If any
charge or better is desirable, especially during winter
voltage is indicated, there is a path that will dis-
weather.
charge the battery. The higher the voltage, the
quicker the discharge rate.
e. Move the negative probe to several locations
(near the positive post) to verify the test results.
Do not attempt to charge a frozen battery. Serious If voltage was detected in the previous test, the battery
injuries to service personnel can result! should be cleaned. The top of the battery may be wiped
off with a damp cloth or washed with a baking soda or
ammonia solution. If the battery is washed, be sure
Maintenance and Troubleshooting none of the cleaning solution is allowed into the battery
cells. Be sure terminals are clean and tight. Clean
Two most common troubles that occur in the charging terminals are very important in a voltage regulated
system are undercharging and overcharging of the system. Be sure to clean the entire battery compart-
truck’s batteries. ment thoroughly as it may contain acid residue. Be
An undercharged battery is incapable of providing careful not to splash any overspray onto surrounding
sufficient power to the truck’s electrical system. components. Rinse the area completely to remove all
traces of battery acid from machine.
D2-2 24VDC Electric Supply System D02020

Leakage can be detected by continual wetness of the BATTERY CHARGING CIRCUIT
battery or excessive corrosion of the terminals, battery COMPONENTS
carrier and surrounding area. (A slight amount of cor-
rosion is normal in lead–acid batteries). Inspect the Batteries - Four (4) 12 volt lead-acid type storage
case, covers and sealing compound for holes, cracks batteries are located on the right hand deck and are
or other signs of leakage. Check battery hold down wired in a series and parrallel combination to provide
connections to make sure the tension is not great 24VDC for the Truck electrical system.
enough to crack the battery, or loose enough to allow
vibration to open the seams. A leaking battery should
be replaced.
To remove corrosion, clean the battery with a solution
of ordinary baking soda and a stiff, non-wire brush and
flush with clean water. Corrosion creates resistance in
the charging circuit which causes undercharging and
gradual starvation of the battery.
NOTE: When washing batteries, make sure cell caps
are tight to prevent cleaning solution from entering the
cells. Alternator - Is located on the upper right front corner
of the engine. The alternator produces 27.5 – 29.5 volt
output and is capable of up to 75 amperes.
Maintaining clean batteries will provide longer service
life and a higher rate of performance. Charge Warning Light - Is located on the left side of
the instrument panel and, when illuminated while the
Spillage engine is running, indicates an abnormality in the
charging system. Normal indicated voltage at high idle
Addition of acid will be necessary if considerable elec- is 27.5 – 29.5 volts.
trolyte has been lost through spillage. Before adding
acid, make sure battery is fully charged. This is accom-
plished by putting the battery on charge and taking
hourly specific gravity readings on each cell. When all
the cells are gassing freely and three successive Before welding on truck, be certain that each of
hourly readings show no rise in specific gravity, the these components are completely disconnected:
battery is considered charged. Additional acid may
now be added. Continue charging for another hour and • Transmission Controller
again check specific gravity. Repeat the above proce- • Batteries
dure until all cells indicate a specific gravity of 1.260-
1.265 corrected to 80°F (27°C). • Battery Charging Alternator
NOTE: Use 1.400 strength sulphuric acid when mak-
ing specific gravity adjustments. Acid of higher
strength will attack the plates and separators before it BATTERY CHARGING ALTERNATOR
has a chance to diffuse into the solution. A 24 volt alternator is used to supply electric current
for the 24VDC circuits when the engine is running. The
If the temperature of the electrolyte is not reasonably alternator is equipped with an internal regulator system
close to 80°F (27°C) when the specific gravity is taken, used to keep the batteries at full charge. Internal
temperature should be corrected to 80°F (27°C): diodes convert the alternator’s AC output to DC.
• For every 10°F (5°C) below 80°F (27°C), 0.004 The only movable part in the assembly is the rotor,
should be SUBTRACTED from the specific gravity which is mounted on a ball bearing at the drive end and
reading. a roller bearing at the rectifier end. All current carrying
conductors are stationary. These conductors are the
• For every 10°F (5°C) above 80°F (27°C), 0.004 field winding, the stator windings, the six rectifying
should be ADDED to the reading. diodes and the regulator circuit components. The regu-
lator and diodes are enclosed in a sealed compart-
ment.
D02020 24VDC Electric Supply System D2-3

A fan located on the drive end provides air flow for Current flow through R1, R2 and R3 causes a voltage
cooling. Grease reservoirs contain an adequate supply to appear at zener diode D4. When the voltage be-
of lubricant so that no periodic maintenance is re- comes high enough due to increasing generator
quired. For repair or maintenance contact your local speed, D4 and the base-emitter of TR3 conduct cur-
Delco-Remy Distributor. rent and TR3 turns on. TR2 and TR1 then turn off,
decreasing the field current and the system voltage
NOTE: The hex head bolt on the output terminal is
decreases. The voltage at D4 decreases, D4 and TR3
electrically insulated; no voltage reading can be ob-
turn off, TR2 and TR1 turn back on and the system
tained by connecting to the hex head.
voltage increases. This cycle then repeats many times
per second to limit the system voltage as determined
by the setting of the potentiometer R2.
Operation
Capacitor C1 protects the generator diodes from high
The basic operating principles are explained as follows transient voltages and suppresses radio interference.
(Refer to Figure 2-1): Resistor R5 prevents current leakage through TR3 at
high temperatures. Diode D5 prevents high transient
As the rotor begins to turn, the permanent magnetism
voltages in the field coil when the field current is
therein induces voltages in the stator windings. The
decreasing. Resistor R7, capacitor C3, and resistor
voltages across the six diodes cause current to flow to
R4, all act to cause transistors, TR2 and TR1, to turn
charge the battery.
on and off more quickly.
Current from the stator flows through the three diodes
to resistor R6 and the base-emitter of TR2 and TR1 to Magnetizing The Rotor
turn these transistors on. Current also flows from the
The rotor normally retains magnetism to provide volt-
stator through the diode trio D1, D2 and D3, the field
age build-up when the engine is started. After disas-
coil and transistor TR1, returning to the stator through
sembly or servicing, however, it may be necessary to
the other three diodes. All stator current, except
reestablish the magnetism. To magnetize the rotor
through the diode trio D1, D2 and D3, flows through
connect the alternator to the battery in a normal man-
the six diodes connected to the stator.
ner, then momentarily connect a jumper lead from the
battery positive post to the relay “R” terminal.
FIGURE 2-1. ALTERNATOR & REGULATOR SCHEMATIC
D2-4 24VDC Electric Supply System D02020

ENGINE PRELUB SYSTEM
DESIGN
When remote lube oil filters are installed, CUMMINS When the pressure switch opens at 2.5 psi (17 kPa),
Engine Co. requires a positive engine oil pressure the circuit to the timer solenoid is opened. After a 3
before starting the engine. This is provided by the second delay, the Prelub starter will stop completely
PRELUB System. and the timer solenoid will provide current to the stand-
ard starter solenoids. The starters and pinion gears will
The use of the prelubrication system will: be engaged into the flywheel ring gear and normal
Reduce the risk of a dry start; cranking will occur.
Pre-fill new oil filters at time of oil change; and
Reduce wear of pressurized friction surfaces due Pressure Switch -
to pressure delays after start-up.
This is a 2.5 psi (17 kPa), normally closed (N/C), switch
The Prelub Starter is an electric starter motor which has that must be located so that it can sense oil pressure
an extended armature shaft to drive an attached oil after the engine oil has passed through the filters.
pump at the brush end of the starter. Normally, this location is the cam cover at the rear of
The total assembly also includes: the engine block.
• an oil pressure switch; Suction Line -
• an oil suction line; The large suction hose (– 20), connects the oil pan
• an oil outlet line; sump to the Prelubrication pump. This hose should not
exceed 56 inches (1422 mm) in length, and it requires
• a check valve; brackets to avoid excessive vibration or rubbing. Re-
• a solenoid timer; and duced hose diameter smaller than a – 20, can result in
reduced pump output.
• an electrical harness.
The Prelub Starter mounting is the same as that used Outlet Line -
for the standard starter. Engine oil is drawn through a The length of the outlet line is not critical, but must be
suction hose that is attached to the oil pan, and then a – 10 hose.
returned to the engine through an outlet line attached
to the engine oil supply ahead of the filters. Check Valve -
NOTE: Before starting engine in cold weather, refer to The oil pressure supply hose will have a check valve
the Operation & Maintenance Manual, Section 3 for installed between the Prelub unit and the engine. The
proper starting procedure. check valve prevents the passage of oil from the engine
back to the pan after the engine is started.
Solenoid Timer -
OPERATION
The solenoid timer controls the prelubrication cycle. It
The Prelub starter is activated when the operator turns
is wired to the key switch. The ground path is com-
the key switch and holds it in the "start" position. The
pleted by the normally closed pressure switch which is
normal starter solenoid is bypassed and the current
preset to open at 2.5 psi (17 kPa). When the switch
flows to the Prelub Starter Solenoid Timer. When this
opens, current is redirected to the standard starter
Solenoid Timer is activated, current flows to the Prelub
solenoid for engine cranking, following a 3 second
Starter motor, but does not engage the starter pinion
delay. Mounting of the timer solenoid is off the engine
gear. The motor drives the Prelub pump assembly
to limit vibration and heat exposure. The solenoid timer
which will deliver approximately 15 gallons of oil per
should not be mounted in an area where a temperature
minute to the engine.
greater than 185°F (85°C) will be experienced.
D02020 24 VDC Electric Supply System D2-5

with Prelub Starter
FIGURE 2-1. SCHEMATIC DIAGRAM
1. Key Switch 4. Starter Safety Relay # 1 7. Prelub Oil Pressure
2. 24VDC Battery (+ ) 5. Starter Safety Relay # 2 Switch (Opens 2.5 psi)
3. Alternator Supply 6. Timer Solenoid 8. Prelub Starter
CIRCUIT CURRENT RATINGS - (MAXIMUM)

A. 15 Amps D. 2 Amps
B. 190 Amps E. 15 Amps
C. 190 Amps
LEGEND FOR WIRE COLORS

WH = WHITE BK = BLACK
OR = ORANGE YL = YELLOW
PK = PINK GN = GREEN
RED = RED WH / BK =
PUR = PURPLE WHITE with BLACK Stripe
D2-6 24 VDC Electric Supply System D02020

with Prelub Starter
Troubleshooting Prelub Starter Circuit
Two distinct phases are involved in a complete prelubrication cycle. The two phases are:
1. Prelubrication Phase- Begins when the key switch is held in the start position. A circuit is provided to ground
through the normally closed pressure switch. The circuit is interrupted upon opening of the pressure switch when
the Prelub pressure reaches 2.5 psi (17 kPa).
2. Delay and Crank Phase- Begins when the pressure switch opens. A 3 second delay precedes the crank mode.
Problem Probable Cause
1. Starter prelubricates only. Does not delay or crank. 1. Indicates oil pressure is not sufficient to open the
pressure switch.
a. No oil or low oil in engine. The pump can not
build sufficient pressure to open switch.
b. Gear pump failure.
c. Pressure switch has failed close and is holding
ground.
d. Oil pressure switch wire chafed and shorting to
block.
2. Starter prelubricates continuously regardless of 2. Indicates Prelub Timer Solenoid contacts have
key switch position. welded.
a. Low voltage can cause relay failure.
b. Jump starting of the vehicle with a voltage that
is higher than was designed for the system, can
cause solenoid contacts to weld.
3. Starter delays and cranks. No prelubrication mode. 3. If an operator indicates the ignition is totally dead,
make certain the key is being held in the crank
position for 3 to 4 seconds. If the engine cranks
after a short delay, this indicates that a ground
connection to the pressure switch has been bro-
ken. Without a ground path, the prelubrication unit
will proceed to delay and crank.
a. Check the wire to the pressure switch. If the wire
is removed or cut, replace it.
b. Check the ground strap to engine block. If the
ground strap is missing the block is not
grounded.
c. Check the pressure switch for an open circuit.
Remove the wire, then check for an open circuit
between the switch terminal and the switch
base. If open, replace the pressure switch.
4. Starting circuit is irregular when in crank mode. 4. a. Check for low or dead batteries.
b. Check alternator output.
c. Check for bad ground strap or NO GROUND
wire from the starter battery ground post to "G"
terminal of starter bendix solenoid.
d. Check for bad starter safety relays.
e. If everything checks OK, replace batteries.
NOTE: Maximum allowable voltage drop is - 2
volts for starter control circuit.
D02020 24 VDC Electric Supply System D2-7

with Prelub Starter
Problem Probable Cause
5. Starter has very long prelubrication cycle. 5. Except for severe cold weather starts, the Prelub
cycle should not exceed 45 seconds.
a. Low oil pressure.
b. Make sure oil of the proper viscosity is being
used in respect to outside temperature. (Refer
to engine manufacturer’s specifications).
c. Check for suction side air leaks, loose connec-
tions, cracked fittings, pump casting, or hose
kinks and blockage.
d. Make sure the suction hose is a – 20. Reducing
hose diameter will reduce pump output dra-
matically.
e. Check the oil pressure switch for the correct
location. Be certain that it has not been moved
into a metered oil flow, as in a bypass filter or
governor assembly.
6. Starter has no prelubrication, no delay and no 6. If the starter is totally inoperative and no prelubri-
crank. cation, no delay and crank, this indicates a possi-
ble failure of the prelubrication timer solenoid.
Remove the wire from the pressure switch (ground
wire) and activate machine starter switch for sev-
eral seconds.
a. If the starter delays- then cranks, the Prelub
Timer Solenoid is bad. Replace the timer sole-
noid assembly.
b. If the starter is still inoperative, check the vehicle
starter switch. Make sure proper voltage is
available to the Prelub Timer Solenoid when the
key is activated.
7. Starter prelubricates, delays, then does not crank. 7. Indication is either a timer failure, or a starter
problem.
a. Pace a jumper wire to the starter solenoid "S"
post. If the engine starts to crank, replace the
Prelub Timer Solenoid.
b. If the engine fails to crank when the "S" post is
energized with voltage, check out starter bendix
solenoid and starter pinion drive.
8. Second starter tries to engage flywheel while pri- 8. Make sure the starter safety relays (4 & 5, Figure
mary starter is prelubricating. 2-1) are wired according to the wiring schematic.
Attempting to activate both starters from the same
starter relay will cause the conventional starter to
crank while the Prelub Starter is pumping.
D2-8 24 VDC Electric Supply System D02020

with Prelub Starter
24VDC ELECTRICAL SYSTEM COMPONENTS
VEHICLE MONITOR SYSTEM
General Description Service Mode

The vehicle monitor system observes the condition of The service mode provides diagnostic information to
the truck systems through sensors installed at various service personnel.
locations. It processes that information and displays it
1. Machine data monitoring mode:
on the monitor panel to inform the operator of the
condition of the machine. The input and output values supplied to the net-
work controller are displayed in real time.
The vehicle monitor system consists of the monitor
panel, various sensors, switches, and relays, alarm 2. Service code, travel data display mode:
buzzer, warning lamps and power source.
Displays the fault codes stored in the network
controllers.
The items displayed can be broadly divided into:
Network Signals
• “Caution” items: Used to display warnings if any
abnormality should occur in the truck. 1. Speed display
• “Gauge” section: constantly displays the condi- 2. Engine speed display
tions, such as gauges, speedometer, tachometer, 3. Shift light display
service meter, odometer, and pilot lamps.
4. Shift position display
5. Speed range display
The monitor panel has a normal mode and a service
mode. 6. Lockup display
7. Automatic gear shift (mechatronics) fault display
Normal Mode
8. Mode selection display
The normal mode primarily displays useful information
to the operator. 9. Air pressure display
1. Items always displayed include: 10. Coolant temperature display
Meters (speedometer, tachometer, service me- 11. Torque converter oil temperature display
ter, odometer). 12. Retarder oil temperature display
Gauges (air pressure, engine coolant tempera- 13. Fuel level display
ture, torque converter oil temperature, retarder oil
temperature, fuel level). 14. Caution/pilot lamp output
2. Items displayed when abnormal conditions occur:
Cautions, Action code display.
D03018 24VDC Electrical Components D3-1

FIGURE 3-1. MONITOR PANEL
D3-2 24VDC Electrical Components D03018

VEHICLE MONITOR PANEL
FIGURE 3-2. ELECTRONIC MONITOR PANEL

1. Air pressure monitor 13. Tachometer 25. Suspension: Soft
2. Air pressure gauge 14. Shift limiter pilot lamp 26. Service Meter
3. Coolant temperature monitor 15. Lockup pilot lamp 27. Service Meter Indicator
4. Coolant temperature gauge 16. Transmission shift position pilot lamp 28. Odometer (total distance
5. Torque converter oil 17. Shift indicator traveled)
temperature monitor 18. Engine controller monitor 29. Power mode indicator (high)
6. Torque converter oil 19. Automatic transmission control 30. Power mode indicator
temperature gauge monitor (economy)
7. Retarder oil temperature 20. Faults in other control systems 31. Right hand module
monitor 32. Center module
21. Fuel level monitor
8. Retarder oil temperature gauge 33. Left hand module
22. Fuel level gauge
9. High beam pilot lamp 34 Speedometer compensation
23. Suspension: Hard
10. Turn signal pilot lamp (left) switch
24. Suspension: Medium
11. Turn signal pilot lamp (right)
12. Speedometer

VEHICLE MONITOR PANEL
The monitor panel consists of the L.H. module, center Specifications: Measuring between pins 1 & 2.
module, R.H. module, service meter, odometer, plate,
25°C (77°F) 37-50 Ω
and other structural parts.
100°C (212°F 3.5-4.5 Ω
The center module has one microcomputer mounted,
and it processes and displays the network and other
signals. • Engine coolant above 102° C (216° F)
A liquid crystal display is used. • Retarder oil above 120° C (248° F)
The monitors and gauges inside the R.H. module and • Torque Converter oil above 120° C (248° F)
L.H. module are actuated by signals from the center
module and the odometer is also actuated by signals
from the center module. AIR PRESSURE SENSOR
The service meter is actuated by a signal from the The air pressure sensor is installed to the air piping
alternator terminal R. behind the operator’s seat. It converts any changes in
the air pressure inside the wet tank to a change in the
SENSORS, SWITCHES resistance, and sends a signal to the shift controller.
ENGINE WATER TEMPERATURE SENSOR The signal is sent from the transmission shift controller
through the network to the machine monitor panel, and
RETARDER OIL TEMPERATURE SENSOR the air pressure is displayed. If the air pressure goes
below the specified pressure (5.3 kg/cm2, 75 psi), the
TORQUE CONVERTER OIL TEMPERATURE monitor panel lamp flashes and the alarm buzzer
SENSOR sounds to warn the operator of the abnormality.
The above sensors (refer to Figure 3-3) are installed

in the retarder oil piping, engine block, and transmis-
sion case.
Any change in the temperature is taken as a change
in the resistance of the thermistor, and a signal is sent
to the shift controller. The signal is then sent from the
shift controller through the network to the machine
monitor panel to display the temperature. When the
monitor panel display reaches a pre-determined value,
a corresponding lamp flashes and the buzzer sounds
to warn the operator of excessive temperature in the
affected system.
FIGURE 3-4. AIR PRESSURE SENSOR
1. Electrical 2. Pressure Tube
Connector
FIGURE 3-3. TEMPERATURE SENSOR

1. Connector 3. Thermistor
2. Plug

FUEL LEVEL SENSOR
The fuel level sensor (Figure 3-5) is installed to the side
face of the fuel tank and a float (4) moves up and down
in accordance with the fuel level. The movement of the
float is passed through an arm (3) to actuate a variable
resistor, sending a signal to the transmission shift
controller. The signal is sent from the shift controller
through the network to the dash monitor system to
display the fuel level. When the display on the monitor
panel reaches a certain position, the warning lamp
flashes.
FIGURE 3-6. ENGINE SPEED SENSOR

1. Magnet 4. Boot
2. Terminal 5. Connector
3. Case
3. Screw in sensor by hand until the tip of sensor

contacts gear tooth - do not force. Do not use a
wrench or other tool to tighten.
4. Turn counter-clockwise 1/4 - 1/2 turn from the
point where sensor contacts gear to obtain clear-
ance “a” (0.4 mm (0.016in.)).
Tighten locknut (2) to 6 ±1 kg.m (43 ±7 ft. lbs.).
FIGURE 3-5. FUEL LEVEL SENSOR 5. Reinstall harness connector. Be certain harness
is properly clamped and supported to prevent
1. Connector 3. Arm strain on connector and wiring.
2. Variable Resistor 4. Float
ENGINE SPEED SENSOR

The engine speed sensor (Figure 3-6) is installed in
the flywheel housing and generates a pulsed voltage
signal which varies in frequency with the speed of the
flywheel ring gear. The voltage signal is then sent to
the transmission shift controller and the monitor panel
to operate the tachometer display.
Adjusting Engine Speed Sensor

1. Disconnect sensor (1, Figure 3-7) electrical con-
nector, loosen locknut (2), and remove sensor.
FIGURE 3-7. ENGINE SPEED SENSOR
NOTE: Inspect sensor tip for iron particles or other ADJUSTMENT
contaminants. Inspect for damage.
2. Verify a gear tooth tip is aligned with the sensor 1. Sensor 3. Flywheel Teeth
mounting hole as shown. (If necessary, rotate 2. Locknut a. 0.4 mm (0.016 in)
flywheel to achieve alignment.)

MONITOR PANEL DISPLAYS
Figures 3-8 through 3-11 list the various monitor panel In addition, each function lists the conditions under
gauges, pilot lamps, caution lamps etc.. Each function which the display is ON or OFF and any additional
is listed in its display category and shows the symbol warnings such as the central warning lamp or buzzer.
(when applicable) that appears on the display area.
FIGURE 3-8. MONITOR PANEL DISPLAYS, FUNCTIONS




INSTRUMENT PANEL INDICATORS,
TEST SWITCH
Figures 3-12 and 3-13 lists the warning and caution The conditions under which the central warning lamp
devices located on the instrument panel, below the will illuminate and the buzzer will sound are listed
Monitor Panel. The central warning lamp, located to
the left of the indicators listed below, can be identified
by its Red convex lens.
FIGURE 3-12. INSTRUMENT PANEL INDICATORS, TEST SWITCH

FIGURE 3-13. INSTRUMENT PANEL INDICATORS, TEST SWITCH

ELECTRONIC ACCELERATOR PEDAL • (AS1) Idle Validation Switch signals
The accelerator pedal provides two digital signals
Operation to indicate whether the accelerator pedal is de-
pressed or released. These signals are used by the
The throttle/accelerator pedal is a foot-operated pedal transmission controller to allow upshift or down
containing a spring-loaded roller arm and inclinded shifts.
ramp, two electrical rheostats and a switch with elec-
trical connectos. • (AS2) pedal (throttle) signal:
This throttle signal is varied as the accelerator
The spring-loaded roller arm is connected to the switch pedal is depressed. As the pedal is depressed, the
and rheostats. As the roller arm travels along the output voltage signal increases and engine rpm
inclined ramp (when the operator depresses the increases. The signal goes to the engine controller.
pedal), electric signals are generated and sent to
various controllers to control fuel (engine rpm), throttle • (AS3) Transmission Controller Throttle signal.
position (pedal depressed/released), and transmis- This throttle signal is varied as the accelerator
sion shift controls. pedal is depressed. The transmission controller
uses this signal, as well as others to determine the
proper timing of up shifts and down shifts for maxi-
mum truck performance.
FIGURE 3-14. ELECTRONIC ACCELERATOR PEDAL

1. Pedal

AISS
(Automatic Idling Setting System)
This switch is used by the operator to control the idle When the switch is "out", normal position, the light in
speed of the engine. The switch when pushed "in" the the switch "OFF", this is the automatic position. In this
light in the switch will be "ON", is in the manual position. position the engine is controlled automatically depend-
This provides for "LOW" engine idle speed. In this ing on operating status of the truck. The following chart
position the operator has greater control for movement outlines the conditions for the engine idle speed.
in confined spaces, such as parking or driving in or out
of service areas.
AISS OPERATIONAL CHART

ENGINE WATER
AISS SWITCH OPERATION OPERATING CONDITION IDLE SPEED
TEMPERATURE
ON Manual - - Low
30°C (90°F) - 50°C (120° F)
Retarder lever operated or parking
OFF automatic (when water temperature is Low
brake applied
above 50°C and goes down)
OFF automatic Above 50°C (120°F) Low
brake applied
30°C (90°F) - 50°C (120°F)
OFF automatic (when water temperature is High
brake applied
below 30°C and goes up)
OFF automatic Below 30°C (90°F) High
brake applied
Retarder lever not operated or
OFF automatic - High
parking brake released

4. Speed sensors are located at three points (trans-
OUTLINE
mission input shaft, intermediated shaft, and out-
This transmission controller is designed to control the put shaft) to make it possible to detect any
system, so it has a built-in computer. It has the follow- slipping of the transmission clutches. It also acts
ing features and functions. to protect the transmission when there is any
abnormality in the hydraulic system.
1. It has a high-power mode and economy mode and
it changes the shift pattern. 5. It is connected to the network and makes various
data common with other controllers.
2. The braking mode is when the brake is being
used. The shifting point is raised and the brake 6. It receives the input of model selection data (what
cooling pump speed increased to improve the machine the controller is mounted on ) and net-
cooling effect for the retarder. At the same time it work data (what controller is connected to the
enables the braking force of the engine to be used network), and contacts the other controllers
effectively. through the network.
3. It drives and controls the torque converter lock-up 7. It has a divided self-diagnostic function for both
solenoid valve, overrun prevention solenoid the input and output system.
valve, exhaust brake solenoid valve, and BCV
8. The content of the self-diagnostic display is shown
solenoid valve.
with 2-digit numbers.
9. When any failure is detected , it sends details to
the network, and displays it on the other display
panels.
FIGURE 3-15. TRANSMISSION CONTROLLER

1. Self Diagnostic Display Window 5. Model Selection Switch (Sw 1) 9. ATC5B
2. Connector 6. Network switch (Sw 2) 10. ATC5A
3. Case 7. ATC2 11. ATC4
4. Printboard 8. ATC1 12. ATC3B
13. ATC3A

10. The content of the self-diagnosis is recorded in OPERATION:
memory, so when the main switch is turned off it
is possible to check details of failures. The automatic shift control system receives the shift
lever position signal, accelerator pedal signal, trans-
11. It sends the trouble data to the network, and mission speed signal, and signals from other switches
displays this on the other display panels. and sensors, and based on the information received
12. The location of any existing failure is displayed on the transmission shift controller acts to automatically
the monitor panel. control the shift of the transmission to the optimum
speed range. The transmission shift controller also
13. It has an emergency travel function for use if there drives and controls the torque converter lockup sole-
is any failure in the electrical system. noid and overrun prevention solenoid valve. Each
14. It is located separately from the gearshift lever. clutch in the transmission is equipped with an elec-
tronically controlled modulation valve and is inde-
pendently controlled.
In addition, based on the information received by the
transmission controller, it drives the monitor panel
display, caution lamps, and pilot lamps and transmits
data to the network.

EXHAUST BRAKE
Outline
The exhaust brake shuts off the exhaust at the exhaust ON position: Actuated when the accelerator pedal is
brake cylinder and makes the engine exhaust stroke released (but only when the torque converter is in
act as an air compressor to increase the effect of the the lock-up condition).
braking force of the engine. The exhaust brake is also
OFF position: Actuated when the foot brake or re-
used as a retarder when going downhill. The exhaust
tarder brake are operated (but only when the
brake is actuated by a signal from the transmission
torque converter is in the lock-up condition).
controller. It acts as follows when the exhaust brake
switch in the operator’s compartment is turned ON or
OFF.
FIGURE 3-16. EXHAUST BRAKE DIAGRAM

1. Exhaust brake switch 6. Transmission controller 11. Accelerator sensor
2. Toque converter lock-up valve 7. Relay 12. Pilot lamp
3. Brake switch 8. Engine controller 13. Retarder control lever
4. Retarder switch 9. Exhaust brake switch 14. Exhaust brake cylinder
5. Exhaust brake solenoid valve 10. Brake valve 15. Battery & Relay

Operation
Operating condition of exhaust brake

The exhaust brake is operated according to the signal
from the transmission controller, and its operation is
as follows when the exhaust brake switch in the opera-
tor’s cab is turned ON and OFF.
ON position: The exhaust brake operates when the
accelerator pedal is released (while the torque
converter is locked up, however)
OFF position: The exhaust brake operates when the
foot brake or retarder brake is operated (while the
torque converter is locked up, however)
Exhaust brake "ON"

FIGURE 3-17. EXHAUST BRAKE ON
When the transmission controller actuates the sole-
noid valve, the following happens.
The solenoid valve opens the port to the exhaust brake
cylinder. Then air flows from the air tank to the exhaust
brake cylinder and causes it to close the exhaust pipe,
and the exhaust brake operates.
Exhaust brake "OFF"

When the transmission controller turns the solenoid
valve "OFF", the solenoid valve closes the port to the
air tank, and opens the port from the exhaust brake
cylinder to the atmosphere.
The air in the exhaust brake cylinder is discharged
through the solenoid valve to the atmosphere. The
exhaust brake cylinder is returned to the original posi-
tion by the spring in it, then the exhaust brake is
released.
FIGURE 3-18. EXHAUST BRAKE OFF

NOTES:

POINTS TO REMEMBER WHEN TROUBLESHOOTING
For this reason, when carrying out troubleshooting, it
is necessary to carry out thorough prior investigation
and to carry out troubleshooting in accordance with the
Stop the machine in a level place, and check that fixed procedure.
the safety pin, blocks, and parking brake are se-
2. Points to ask the operator
curely fitted.
a. Have any other problems occurred apart from
When carrying out the operation with two or more the problem that has been reported?
workers, keep strictly to the agreed signals, and
b. Was there anything strange about the machine
do not allow any unauthorized person to come
before the failure occurred?
near.
c. Did the failure occur suddenly, or were there
If the radiator cap is removed when the engine is problems with the truck condition before this?
hot, hot water may spurt out and cause burns, so
d. Under what conditions did the failure occur?
wait for the engine to cool down before starting
troubleshooting. e. Had any repairs been carried out before the
failure?
Be extremely careful not to touch any hot parts or
f. Has the same kind of failure occurred before?
to get caught in any rotating parts.
3. Check before troubleshooting
When disconnecting wiring, always disconnect
the negative (-) terminal of the battery first. a. Check for symptoms of any abnormality with
the truck.
b. Check the CHECKS BEFORE STARTING
items.
c. Other inspection items.
When removing the plug or cap from a location
d. Other maintenance items can be checked ex-
which is under pressure form oil, water, or air,
ternally, so check any item that is considered
always release the internal pressure first. When
to be necessary.
installing measuring equipment, be sure to con-
nect it properly. 4. Confirming failure
Confirm the extent of the failure yourself, and
The aim of troubleshooting is to pinpoint the basic
judge whether to handle it as a real failure or as
cause of the failure, to carry out repairs swiftly, and to
a problem with the method of operation, etc.
prevent reoccurrence of the failure.
• When operating the truck to re-enact the trou-
When carrying out troubleshooting, and important bleshooting symptoms, do not carry out any
point is of course to understand the structure and investigation that may make the problem
function, However, a short cut to effective trou- worse.
bleshooting is to ask the operator various questions to
form some idea of possible causes of the failure that 5. Troubleshooting
would produce the reported symptoms. Use the results of the investigation and inspection
in Items 2 - 4 to narrow down the causes of failure,
1. When carrying out troubleshooting, do not hurry then use the troubleshooting flowchart to locate
to disassemble the components. the position of the failure exactly.
If components are disassembled immediately any • Basic procedure for troubleshooting is below.
failure occurs:
a. Start from the simple points.
• Parts that have no connection with the failure
or other unnecessary parts will be disassem- b. Start from the most likely points.
bled. c. Investigate other related parts or information.
• It will become impossible to find the cause of 6. Measures to remove root cause of failure
the failure. Even if the failure is repaired, if the root cause of
It will also cause a waste of man-hours, parts, or the failure is not repaired, the same failure will
oil or grease, and at the same time, will also lose occur again. To prevent this, always investigate
the confidence of the operator. why the problem occurredthen remove the cause.
D04009 Introduction to Electrical Troubleshooting D4-1

POINTS TO REMEMBER WHEN CARRYING OUT MAINTENANCE
To maintain the performance of the truck over a long
period, and to prevent failures or other troubles before
they occur, correct operation, maintenance and in-
spection, troubleshooting, and repairs must be carried
out. This section deals particularly with correct repair
procedures for mechantronics and is aimed at improv-
ing the quality of repairs.
POINTS TO REMEMBER WHEN HANDLING

ELECTRIC EQUIPMENT
1. Handling wiring harnesses and connectors
Wiring harnesses consist of wiring connector used to
connect one component to another component. Con-
nectors used for connecting and disconnecting one
wire from another wire, and protectors or tubes used
for protecting the wiring.
Unlike other electrical components fitted in boxes or
cases, these wiring harnesses (Figure 4-1) are more
FIGURE 4-1. AFFECTS OF WEATHER
likely to be affected by rain, water, heat, or vibration.
Furthermore, during inspection or repair operations,
they are frequently removed and reinstalled, so they
are likely to suffer deformation or damage. For this
reason, it is necessary to be extremely careful when
handling wiring harnesses.
2. Failures that occur in wiring harness

a. Defective contact of connectors (Figure 4-2)
caused by faulty connectors or connector pins.
Problems with defective connectors are likely
to occur because the male connector is not FIGURE 4-2. IMPROPER INSERTION
properly inserted into the female connector, or
one or both of the connectors are deformed.
Also because there is corrosion or oxidization
of the pin surfaces.
b. Defective crimping or soldering of pins (Figure
4-3). The pins of the male and female connec- Improper Crimp
tors are in contact with this wire at the crimped
terminal or soldered joint.
However, if the crimp or solder joint is improp-
erly completed, oxidization can occur causing
a break in the electrical connection.
FIGURE 4-3. IMPROPER CRIMP
D4-2 Introduction to Electrical Troubleshooting D04009

c. Damage to wiring during disconnecting
connectors
If the connectors are pulled apart by pulling on
the wires or components are removed with the
wires still connected, damage to the pin termi-
nals, solder joints, connector or the wires can
occur.
d. High-pressure water entering connector

The connector is designed to make it difficult
for water to enter (drip-proof structure), but if
high-pressure water is sprayed directly on the
connector, water may enter the connector, de-
FIGURE 4-4. IMPROPER HANDLING
pending on the direction of the water jet.
As already said, the connector is designed to

prevent water from entering, but at the same
time, if water does enter, it is difficult for it to be
drained. Therefore, if water should get into the
connector, the pins will be short-circuited by
the water. So if any water gets in, immediately
dry the connector or take other appropriate
action before allowing current to flow through
it.
e. Oil or dirt in the connector

If oil or grease have entered the connector, an FIGURE 4-5. WATER COROSION
oil film can be formed on the mating surface
between the male and female pins, this oil film
will not let the current to pass, so there will be
an open contract.
If there is oil or grease on the connector, wipe
it off with a dry cloth or blow it dry with com-
pressed air and spray it with a contact cleaner.
• When wiping the mating portion of the connec-

tor, be careful not to use excessive force or
deform the pins.
• If there is oil or water in the compressed air, the
contacts will become even dirtier, so remove
the oil and water from the compressed air
completely before cleaning the connections.
FIGURE 4-6. CLEANING THE CONNECTOR

3. Removing, installing, and drying connectors
and wiring harnesses.
1. Disconnecting connectors
Hold the connectors when disconnecting (Figure
4-7). When disconnecting the connectors, hold
the connectors and not the wires. For connectors
held by a screw, loosen the screw fully, then hold
the male and female connectors in each hand and
pull apart. For connectors which have a lock tab, FIGURE 4-7. DISCONNECTING CONNECTORS
press down the tab with your thumb and pull the
connectors apart.
NOTE: Never pull with one hand.
2. When removing from clips

When removing a connector from a clip, pull the
connector in a parallel direction from the clip
(Figure 4-8).
NOTE: If the connector is twisted up and down or to FIGURE 4-8. CONNECTOR CLIPS
the left or right, the housing may break (Figure 4-9).
3. Action to take after removing connectors

After removing any connector, cover it with a vinyl
bag to prevent any dust, dirt, oil, or water from
getting in the connector (Figure 4-10).
NOTE: If the truck is left disassembled for a long time,
it is particularly easy for contamination of the contactor
to occur, so always cover the connector.
FIGURE 4-9. CATCHES
FIGURE 4-10. COVERING CONNECTOR

4. Connecting Connectors
1. Check the connector visually.
a. Check that there is no oil, dirt, or water in the
connector pins (mating portion).
b. Check that the connector is not deformed,
defective contact, corrosion, or damage to the
connector pins.
c. Check that there is no damage or breakage to
the outside of the connector.
NOTE: If there is any oil, water, or dirt in the connector,
wipe it off with dry cloth. if any water has got inside the
connector, warm the inside of the wiring with a dryer,
but be careful not make it too hot as this will cause
damage.
NOTE: If there is any damage or breakage, replace the FIGURE 4-11. CONNECTING CONNECTORS
connector.
2. Install the connector properly

a. Align the position of the connector correctly,
then insert it securely.
b. For connectors with locking tabs, push in the
connector until the tab clicks into position.
3. Correct any protrusion of the boot and any mis-

alignment of the wiring harness.
For connectors fitted with boots, correct any
protrusion of the boot. In addition, if the wiring
harness is misaligned, or the clamp is out of
position, adjust it to its correct position.
NOTE: If the connector cannot be corrected easily,
remove the clamp and adjust the position.
FIGURE 4-12. INSTALLING CONNECTOR
NOTE: If the wiring harness or connector has been
removed from a clamp, be sure to return it to its original
position. Check also that there are no loose clamps.
FIGURE 4-13. HARNESS CLAMPS

4. Drying wiring harness
If there is any oil or dirt on the wiring harness, wipe it
off with a dry cloth. Avoid washing it in water or using
steam. If the connector must be washed in water, do
not use high-pressure water or steam directly on the
wiring harness.
If water gets directly on the connector, perform the
following:
a. Disconnect the connector and wipe off the
water with a dry cloth.
b. If the connector is blown dry with compressed
FIGURE 4-14. CLEANING THE CONNECTOR
air, there is the risk that oil in the air may cause
defective contact, so remove all oil and water
from the compressed air before blowing with
air.
Drying the inside of the connector with a dryer.

If water gets inside the connector, use a dryer to dry
the connector.
NOTE: Hot air from the dryer can be used, but regulate
the time that the hot air is used in order not to make
the connector or related parts too hot. This may cause
deformation or damage to the connector.
Carry out a continuity test on the connector.

FIGURE 4-15. DRYING THE CONNECTOR
After drying, leave the wiring harness disconnected
and carry out a continuity test to check for any short
circuits between pins caused by water.
After completely drying the connector, blow it with
contactor cleaner and reassemble.
FIGURE 4-16. TESTING THE CONNECTOR

Handling of controller boxes
The controller box contains a microcomputer and elec-
tronic circuits. These control all of the electronic cir-
cuits on the truck so be extremely careful when
handling the box.
• Do not open the cover of the controller box
unless necessary.
• Do not place objects on top of the controller
box.
• Cover the connectors with tape or a vinyl bag.
• Never touch the connector contacts with your
hand.
• During rainy weather, do not leave the control-
ler box in a place where it is exposed to the
weather.
• Do not place the control box on oil, water, or
dirt, or in any hot place, even for a short time.
Place it on a suitable dry stand.
FIGURE 4-17. CONTROLLER BOX
Precautions when performing arc welding on the
truck.
• Disconnect all wiring harness connectors con-
nected to the controller box. Attach the arc
welding ground close to the welding point.
Points to remember when troubleshooting

electric circuits
• Always turn the power OFF before disconnect-
ing or connect connectors.
• Before carrying out troubleshooting, check that
all the related connectors are properly con-
nected.
• Disconnect and connect the related connec-
tors several times to check.
• Always connect any disconnected connectors
before going on to the next step.
• If the power is turned ON with the connectors
still disconnected, unnecessary abnormality
displays will be generated.
FIGURE 4-18. THINGS NOT TO DO
• When carrying out troubleshooting of circuits
(measuring the voltage, resistance, continuity,
or current), move the related wiring and con-
nectors several times and check that there is
no change in the reading of the tester. If there
is any change, there is probably defective con-
nection in that circuit.

5. POINTS TO REMEMBER WHEN HANDLING
HYDRAULIC EQUIPMENT
With the increase in pressure and precission of hy-

draulic equipment, the most common cause of failure
is dirt (foreign material) in the hydraulic system. When
adding hydraulic oil, or when disassembling or assem-
bling hydraulic equipment, it is necessary to be par-
ticularly careful.
Be careful of the operating environment.

Avoid adding hydraulic oil, replacing filters, or repairing
the truck in rain, or high winds, or places where there
is a lot of dust.
FIGURE 4-19. IMPROPER OIL HANDLING
Disassembly and maintenance work in the field
If disassembly or maintenance work is carried out on
hydraulic equipment in the field, there is danger of dust
entering the equipment. It is also difficult to confirm the
performance after repairs, so it is desirable to use unit
exchange. Disassembly and maintenance of hydraulic
equipment should be carried out in a specially pre-
pared dustproof workshop, and the performance
should be confirmed with special test equipment.
Sealing openings
After any piping or equipment is removed, the open-
ings should be sealed with caps, tapes, or vinyl bags
to prevent any dirt or dust form entering. If the opening
is left open or is blocked with a rag, there is danger of
dirt entering or of the surrounding area being made
FIGURE 4-20. OIL PUMP WITH FILTER
dirty by leaking oil.
Do not simply drain oil out on to the ground, collect it
and dispose of it properly.
Do not let any dirt or dust get in during refilling

operations.
Be careful not to let any dirt or dust get in when re-filling
with hydraulic oil. Always keep the oil filler and the area
around it clean. Also use clean pumps or oil containers.
If an oil cleaning device is used, it is possible to filter
out the dirt that has collected during storage, so this is
an even more effective method.

Changing oil when the temperature is high.
When oil is warm, it flows easily. In addition, the sludge
can also be drained out easily from the system to-
gether with the oil. So it is best to change the oil when
it is still warm. When changing the oil, as much as
possible of the old oil should be drained out. (Drain the
oil from the tank; also drain the oil from the filter and
from the drain plug in the system). If any old oil is left,
the contaminants and sludge in it will mix with the new
oil and will shorten the life of the oil.
Flushing operations
After disassembling and assembling the equipment, or
changing the oil, use flushing oil to remove the con-
taminants, sludge, and old oil from the system.
Normally, flushing is carried out twice: primary flushing
is carried out with flushing oil, and secondary flushing
is carried out with the specified oil. FIGURE 4-21. OIL FLUSHING
Cleaning operations
After repairing the equipment (pump control valve,
etc.) or when running the truck, carry out oil cleaning
to remove the sludge or contaminants in the oil circuit.
The oil cleaning equipment is used to remove the ultra
fine (about 3u) particles that the filter built into the
equipment cannot remove, so it is an extremely effec-
tive device.
FIGURE 4-22. OIL PUMP WITH FILTER

CHECKS BEFORE TROUBLESHOOTING
(1. Checks before starting, 2. other check items)
Item Standard value Action

1. Check fuel level Fuel gauge Add fuel
2. Check for dirt or water in fuel - Clean, drain
3. Check for water in air tank - Drain
Air Circuit,
4. Check transmission oil level Oil level gauge Add oil
hdraulic oil,
5. Check hydraulic oil level Sight gauge Add oil
lubricating oil,
6. Check engine oil level (Level of oil in oil pan) Oil level gauge Add oil
cooling water,
7. Check cooling water level - Add water
8. Check condition of dust indicator Dust indicator Clean
9. Check front brake oil level (Level of oil in tank) Oil level gauge Add oil
10. Check for water in emergency brake air tank - Drain
11. Check play of steering wheel 100-140 mm -
12. Check operation of emergency steering Operation: 20 sec. Repair
13. Check length of suspension for proper charge Label Adjust
14. Check tire inflation pressure and damage - Charge air
1. 15. Check wheel mounting nuts - Tighten
Air,
16. Check operation of service brake - Adjust
Checks hydraulic,
17. Check operation of parking brake - Adjust or repair
before mechanical
18. Check operation of emergency brake - Adjust or repair
starting components
19. Check abnormality of steering - Adjust or repair
20. Check the right and left view mirror - Adjust
21. Check exhaust color and for abnormal noise - Adjust or repair
22. Check operation of retarder brake - Adjust or repair
23. Check wear of body rubber pads - Adjust or repair
- Repair
24. Check air horn
- Repair or replace
25. Check function of lights
- Adjust or repair
26. Check function of gauges
- Adjust or replace
27. Check monitor panel
Electrical - Repair or replace
28. Check truck monitor system
equipment - Repair or replace
29. Check central warning light
- Re-tighten or clean
30. Check for loose or corroded battery terminals
31. Check for loose or corroded alternator terminals
32. Check for loose or corroded starting motor terminals

Item Standard value Action
Hydraulic, 33. Check abnormal noise or smell - Repair
Mechanical 34. Check for oil leakage - Repair
components 35. Bleed air from all systems - Bleed air
36. Check battery voltage (engine stopped)
Replace
37. Check level of battery electrolyte
2. 20-30 V Add or replace
38. Check for discolored, burnt, or bare wiring
- Replace
39. Check for missing wiring clamps, hanging wire
Other check - Repair
40. Checks for water leaking onto wiring
Items Electrical - Disconnect connector
(check carefully water leakage at connectors and terminals)
components - and dry connection
41. Check for broken or corroded fuses
- Replace
42. Check alternator voltage
27.5-29.5V Replace
(engine running at over half throttle)
- Replace
43. Noise when battery relay is operated.
(Switch starting switch from ON to OFF)

TYPE OF CONNECTOR AND POSITION OF INSTALLATION
The address column in this table shows the address in the connector pin allocation drawing.
The connector number listed in the charts may be preceeded with a "CN-" on the actual drawing.
Con Con No. Con Con No.

Add Add
nector nector of MOUNTING LOCATION nector nector of MOUNTING LOCATION
ress ress
No. Type pins No. Type pins
01 SWP 14 Intermediate connector A6 1-pin
34 1 Clearance lamp A5
02 SWP 8 Intermediate connector A6 conn.
03 X 2 Radiator water level sensor A4 1-pin

35 1 Clearance lamp A5
conn.
04 X 2 Air conditioner pressure switch A3
1-pin
06L - 3 Head lamp (Lo) D1 36 1 Turn signal lamp A5
conn.
07H - 3 Head lamp (Hi) D1 1-pin
37 1 Fog lamp A5
1-pin conn.
08 1 Clearance lamp E1
conn. 39 X 3 Suspension pressure sensor A6
1-pin 40 SWP 6 Payload meter display lamp (right) B7
09 1 Clearance lamp F1
conn.
41 M 1 Right side lamp C7
1.PS x 2 Transmission solenoid valve Q1
51 X 2 Flow switch F9
1.SW x 1 Fill switch Q1
52 X 2 Transmission oil filter sensor L4
2.PS x 2 Transmission solenoid valve Q1
53 X 2 Retarder filter sensor L6
2.SW x 1 Fill switch P1
54 X 2 Hydraulic oil filter sensor L6
3.PS x 2 Transmission solenoid valve P4
55 X 2 BCV solenoid L8
59 SWP 6 Tail lamp J8
4.PS x 2 Transmission solenoid valve P4
60 SWP 6 Tail lamp K8
61 X 1 Fuel gauge sensor G9
1pin-
10 1 Turn signal lamp E1 62 X 3 Suspension pressure sensor K8
conn.
1pin 63 X 3 Suspension pressure sensor J9
11 1 Fog lamp E1
conn. 64 X 2 Retarder oil temperature sensor J8
12 - 2 Washer motor A6 1-pin
76 1 Auto drain valve heater B7
13 x 3 Suspension pressure sensor A4 conn.
Payload meter external display Emergency stop solenoid

14 SWP 6 L4 84 - 2 (mechanical governor A4
lamp (left)
specification)
15 M 1 Left side lamp L3
AISS motor (mechanical governor
17 - 1 Air conditioner compressor A4 86 - 8 -
specification)
18 - 2 Diode A4 Engine stop motor (mechanical
87 - 8 -
20 SWP 14 Intermediate connector A5 governor specification)
21 X 1 Steering oil temperature sensor L5 90 - 2 Diode L8
24 X 2 Starting motor A3 99 - 2 Intermediate connector -
CTI X 2 Water temperature A3 A1 KES1 1 Emergency escape switch T1
EPI - 1 Engine oil pressure sensor A4 A2 KES 1 Emergency escape switch T1
Emergency stop solenoid AC1 M 4 Intermediate connector N7
28 - 2 (mechanical governor A3 Al - 7 AISS switch M4
specification)
AS1 X 2 Exhaust brake switch S9
30 SWP 14 Intermediate connector B7
AS2 X 2 Parking brake switch T9
31 SWP 8 Intermediate connector A6
AS3 X 2 Retarder brake switch T9
32H - 3 Head lamp (Hi) A5
AS4 X 2 Emergency brake switch S9
33L - 3 Head lamp (Lo) A5
AS5 X 2 Service brake switch T9
ATC1 MIC 17 Transmission controller U1

Con Con Con Con
No. of Add No. of Add
nector nector MOUNTING LOCATION nector nector MOUNTING LOCATION
pins ress pins ress
No. Type No. Type
ATC2 MIC 21 Transmission controller U4 DB1 X 4 Body seated switch J9
ATC3A AMP040 20 Transmission controller U4 DB4 - 2 Diode -
ATC3B AMP040 16 Transmission controller U4 DLB X 2 Differential lock switch S8
ATC4 AMP040 12 Transmission controller V3 DP01 MIC 5 Monitor panel O6
ATC5A AMP040 20 Transmission controller V3 DP02 AMP040 8 Monitor panel P9
ATC5B AMP040 16 Transmission controller U3 DP03 Socket 2 Monitor panel O6
ATC6 X 4 Transmission controller T2 DP04 AMP040 8 Monitor panel P9
BLSL X 2 Brake stroke sensor K8 DP05 AMP040 12 Monitor panel P6
BLSR X 2 Brake stroke sensor I9 DP06 Socket 2 Monitor panel P9
BT1 - - Fuse box U5 DP07 Socket 2 Monitor panel Q9
BT2 - - Fuse box T6 DP08 AMP040 16 Monitor panel Q9
BT3 - - Fuse box T6 DP09 Socket 2 Monitor panel R8
BZ M 2 Alarm buzzer O6 DP10 AMP040 8 Monitor panel R8
C1 - 1 Intermediate connector U4 DP11 AMP040 16 Monitor panel R8
C2 - 1 Intermediate connector T4 DP12 M 4 Monitor panel R7
1-pin DP13 Socket 2 Moniro panel R8
CA+ 1 AM/FM cassette N9
conn. EXH Socket 7 Exhaust brake switch O5
1-pin
CA- 1 AM/FM cassette N9
conn.
1-pin
CAB 1 AM/FM cassette N9
conn.
1-pin
CG1 1 Cigar lighter M6
conn.
1-pin
CG2 1 Cigar lighter M6
conn.
CK1 KES1 2 Bulb check switch M5
CM S 8 Combination switch Q8
CNS S 12 Intermediate connector V2
Transmission oil
C/V.T X 2 P1
temperature sensor
D04 - 2 Diode S7
D05 - 2 Diode X6
D06 - 2 Diode X5
D08 - 2 Diode N4
D1 - 2 Diode B2
D1 - 10 Message display X1
1-pin
D5-1 1 Horn valve C2
conn.
1-pin
D5-2 1 Horn valve B2
conn.
D12 - 2 Diode M5
D14 - 2 Diode S7

Con Con Con Con
nector nector MOUNTING LOCATION nector nector MOUNTING LOCATION
pins ress pins ress
No. Type No. Type
FB PA 7 Front brake sut switch O5 MS11 M 1 Model selection switch T1
FCM - 7 Intermediate connector R6 MS12 M 1 Model selection switch S2
FCS - 7 Intermediate connector R6 N1 X 2 Input shaft speed sensor O1
FL PA 7 Fog lamp switch O6 N2 X 2 Intermediate shaft speed sensor O1
FU - 2 Fuse unit B7 N3 X 2 Output shaft speed sensor Q4
HAZ socket 7 Hazard switch O5 P15 M 2 MPH selection connector P6
HEAT M 1 Heater N6 PL1 S 10 Monitor lamp M5
1-pin Suspension pressure sensor
HN 1 Horn Q9 PL1 - 2 H1
conn. GND selection connector
H.PS X 2 Transmission solenoid valve O3 PL2 S 10 Monitor lamp M5
H.SW X 1 Fill switch O3 Suspension pressure sensor
PL2 - 2 H1
HT PA 7 Preheat switch M5 GND selection connector
Intermediate connector PLS M 4 Monitor lamp M4

J01 S 16 S7
inside, outside cab PM1 MIC 21 Payload meter M9
Intermediate connector PM2 M 4 Payload meter I1
J02 S 16 S8
inside, outside cab PM3 X 3 Clinometer L4
Intermediate connector PM4 M 6 Intermediate connector M9
J03 S 16 S8
inside, outside cab
PM5 MIC 13 Payload meter (card type) M8
Intermediate connector
J04 S 12 T9 AMP04
inside, outside cab PM6 12 Payload meter (card type) M8
0
J06 terminal 1 S7 Suspension pressure sensor FR
inside, outside cab PM6 KES1 2 S2
selection connector
J07 terminal 1 S7 PM7 MIC 9 Payload meter (card type) M7
inside, outside cab
J09 S 12 Intermediate connector - PM7B MIC 9 Payload meter (card type) N7
J10 S 16 Intermediate connector - PM8 MIC 5 For connecting PC G1
J11 S 12 Intermediate connector -
Torque converter lock-up
L/C.T X 2 N3
solenoid
LPS X 2 Transmission solenoid valve O3
LS M 3 Rheostat R7
LSW X 1 Fill switch sensor O3

Con Con No. Con Con No.
Add Add
nector nector of MOUNTING LOCATION nector nector of MOUNTING LOCATION
ress ress
No. Type pins No. Type pins
PMCD X 2 For off-board PMC power source U5 R29 socket 6 Hazard lamp relay X8
PMR1 S 16 Intermediate connector V5 RAD - 9 AM radio O6
PMR2 S 12 Intermediate connector V5 RE1 socket 1 Resistor R6
PMR3 S 16 Intermediate connector X5 RE2 socket 1 Resistor R6
PMR4 S 16 Intermediate connector X5 RH1 S 10 Intermediate connector X7
PMRA S 12 Intermediate connector H9 RH2 S 12 Intermediate connector S2
PMRB S 12 Intermediate connector I9 RH4 S 8 Intermediate connector X8
PMRC S 16 Intermediate connector I9 1-pin
RL 1 Room lamp U9
PMS S 12 Intermediate connector X6 conn.
PW PA 7 Power mode switch V3 RPS X X Transmission solenoid valve Q4
Suspension pressure sensor FR RSW X X Fill switch sensor P4

PWR KES1 2 S3
selection connector RT1 terminal 1 Timer for emergency steering S5
R01 socket 5 Engine starting relay V5 RT2 terminal 1 Timer for emergency steering S5
R02 socket 5 Transmission neutral relay U5 RT3 terminal 1 Timer for emergency steering S5
R03 socket 5 Service brake relay T6 RT4 terminal 1 Timer for emergency steering S5
R04 socket 5 BCV relay S7 RT5 terminal 1 Timer for emergency steering S5
R05 socket 5 Backup alarm relay S7 RT6 terminal 1 Timer for emergency steering S5
R06 socket 5 Head lamp relay (Hi) W5 RT7 terminal 1 Timer for emergency steering S5
R07 socket 5 Marker lamp relay W5 RT8 terminal 1 Timer for emergency steering S5
R08 socket 5 Head lamp relay (Lo) T6 Selection connector for each
R09 socket 6 Rear brake pilot relay T6 SCF KES1 2 suspension pressure sensor X6
specification
R11 socket 6 Payload meter relay S8
Selection connector for each
Payload meter external display SCFR KES1 2 suspension pressure sensor X5
R16 socket 5 X7
lamp relay specification
Payload meter external display SF S 12 Gearshift lever V1
R17 socket 5 X7
lamp relay
SH socket 7 Shift limit switch V2
Payload meter external display
R18 socket 5 W8 SL1 X 2 Suspension control solenoid X8
lamp relay
Payload meter external display SL2 X 2 Suspension control solenoid W9
R19 socket 5 V9
lamp relay SL3 X 2 Suspension control solenoid U9
Payload meter external display SL4 X 2 Over-run prevention solenoid W8
R20 socket 5 S8
lamp relay SL5 X 2 Exhaust brake solenoid W9
R21 socket 5 Parking brake relay X7 SL6 X 2 Front brake cut-off solenoid V9
Governor cut relay (electronic SL7 X 2 Front brake cut-off solenoid U9
R22E socket 5 X8
governor specification)
SNUB X 2 AISS relay resistor W8
Governor cut relay (electronic
R23E socket 5 W9 1-pin
governor specification) SP1 1 AM/FM cassette O9
conn.
R25 socket 5 Transmission cut relay V9
1-pin
R27 socket 5 Hazard relay T9 SP2 1 AM/FM cassette O9
conn.
R28 socket 6 Hazard lamp relay X7 1-pin
SP3 1 AM/FM cassette O9
conn.
1-pin
SP4 1 AM P9
conn.

Con Con
No. of Add
nector nector MOUNTING LOCATION
pins ress
No. Type
1-pin
SP5 1 Speaker (right) U9
conn.
1-pin
SP6 1 Speaker (right) V9
conn.
1-pin
SP7 1 Speaker (left) I2
conn.0
1-pin
SP8 1 Speaker (left) I2
conn.
SR2 X 3 Steering sensor C1
SR3 X 2 Tilt sensor U5
SR4 M 3 Bimetal timer S6
SR5 X 2 Air pressure sensor S8
SSP1 MIC 21 Suspension controller T4
SSP2A AMP040 20 Suspension controller T4
SSP2B AMP040 16 Suspension controller T4
SU3 S 16 Intermediate connector W5
Selection connector for each
SU6 KES1 2 suspension pressure sensor S3
specification
Torque converter oil
TC.SE X 2 N2
temperature sensor
Torque converter oil
TC.SW X 2 N2
temperature switch
TM2 SWP. 14 Intermediate connector R2
TM3 SWP 14 Intermediate connector R3
TM4 SWP 14 Intermediate connector R3
TMA S 16 Intermediate connector V5
TMB S 16 Intermediate connector V5
TMC S 12 Intermediate connector W5
TMD S 16 Intermediate connector X5
WAS1 S 6 Acceleration sensor C2
Acceleration sensor
WAS2 X 3 (electronic governor A3
specification)
WL M 2 Caution lamp O4
WP1 S 8 Wiper switch N4
WP2 KES1 6 Wiper motor relay F1
WP3 KES0 6 Intermittent wiper relay R7

FOR ARSC ( AUTOMATIC RETARDER SPEED CONTROL)
Con Con Con Con

nector nector Place of use nector nector Place of use
pins ress pins ress
No. Type No. Type
1-8 X 1 Selection connector d4 R4 Terminal 1 Travel speed display -
1-pin R5 Terminal 1 Travel speed display -
78/98 1 Model selection connector d4
conn. R6 Terminal 1 Travel speed display -
8S X 1 Selection connector d4 RB For relay 5 RB relay Y7
250 - 2 Resistor a3 RW For relay 6 RW relay Y6
1020 - 2 Resistor Z3 RZ For relay 5 RZ relay Y6
1-pin SHIFT X 1 Selection connector c4
A1 1 ARSC caution lamp Z3
conn.
SHUT - 2 Air shut-off valve D8
1-pin
A2 1 ARSC caution lamp Z3 SOSW X 2 Air switch (air shut-off valve) D8
conn.
1-pin Suspension pressure
A6 1 ARSC stand-by lamp Y4 SP2 M 2 Z7
conn. selection connector
ARC1 MIC 21 ARSC controller Y6 Power source for
SP4 M 2 suspension pressure sensor c8
ARC2 AMP040 20 ARSC controller Y6 /sensor GND connection
ARC3 AMP040 16 ARSC controller a6 Power source for
BRJ M 8 Intermediate connector a8 suspension pressure
SP5 M 2 c8
BRR X 2 Air switch (brake solenoid) D8 sensor/sensor GND
connection
BSOR - 2 Brake solenoid valve (right) D8
Suspension pressure
BT3 - - Fuse box d4 SPR M 2 Z7
selection connector
BZ-EL1 M 2 Buzzer b3 SPSW M 3 ARSC set switch b3
BZ-EL2 M 2 Buzzer b3 SW - 7 ARSC system switch c3
CR1 M 1 For clearing error code a8 Tire large diameter/small
TIRE1 X 1 c4
CR2 M 1 For clearing error code b8 diameter selection
D01 - 2 Diode d6 Tire large diameter/small
TIRE2 X 1 c4
diameter selection
D02 - 2 Diode d5
TMA1 X 16 Intermediate connector d7
D03 - 2 Diode d6
TMA2 X 16 Intermediate connector d5
1pin
FS1 1 Spare terminal d5 TMB1 X 16 Intermediate connector d7
conn.
J02-EL1 S 16 Intermediate connector b8 TMB2 X 16 Intermediate connector d5
J02-EL2 S 16 Intermediate connector c8 TMC1 X 12 Intermediate connector d7
J04-EL1 S 12 Intermediate connector c8 TMC2 X 12 Intermediate conector d5
J04-EL2 S 12 Intermediate connector c7 TMD1 X 16 Intermediate connector d7
1-pin TMD2 X 16 Intermediate connector d6
KO 1 ARSC stand-by lamp Y4
conn. WL-
M 2 Warning lamp b3
PH1- EL1
S 10 Intermediate connector d6
EL1 WL-
M 2 Warning lamp b3
PH1- EL2
S 10 Intermediate connector d6
EL2
PM4-1 M 6 Payload meter Y5
PM4-2 M 6 Payload meter Y5
R2 Terminal 1 Travel speed display -
R3 Terminal 1 Travel speed display -

CONNECTOR PIN ALLOCATION CHART
FIGURE 4-23. CONNECTOR LOCATIONS


CONNECTOR PIN ALLOCATION CHART
FIGURE 4-25. CONNECTOR LOCATION


FIGURE 4-27. CONNECTOR LOCATION

CONNECTION TABLE FOR CONNECTOR PIN NUMBERS
The terms male and female refer to the pins, while the terms male housing and female housing re fer to the mating
portion of the housing.

EXPLANATIONS OF FUNCTIONS (CONTROL MECHANISM) OF
ELECTRICAL SYSTEM
This section gives the necessary knowledge for trou- When the self-diagnostic display function is actuated,
bleshooting of the electrical system, and explains the the abnormality occurrence data is transmitted from
functions and nature of checks for the transmission each controller to the net-work, and the monitor panel
controller, monitor panel and if equipped, the suspen- displays the action code. The abnormality is displayed,
sion controller. warning lamp, and buzzer may also be actuated. The
service codes which display the causes of these prob-
lems can be seen by pushing the bulb check switch.
In addition, the controllers share some of the sensor
1. EXPLANATION OF FUNCTIONS
signals, such as the transmission out-put shaft speed
The control mechanism of the electrical system con- signal. So if any abnormality occurs in these sensor
sists of the transmission controller, monitor panel and signals, the same type of failure display maybe occur
the suspension controller (if equipped). They carry out for another controller.
various controls such as changing the output of the
Signal inputs from the switches and relay listed below,
engine (power mode), providing the most suitable
do not have a self-diagnostic display. If the operation
transmission clutch oil pressure (full electronic modu-
of the truck is abnormal, to check cause refer to
lation), and changing the damping of the suspension
"checking Operation of Electrical System" in this Sec-
(auto suspension).
tion.
The monitor panel informs the operator of the abnor-
mality when there is a failure in the equipment for each
system. At the same time, it uses the service mode to Switches:
monitor the input and output, such as the in-put voltage
• Shift Limiter
from the switch sensors of each controller and the
output current to the solenoids, and a monitor function • Power Mode
for the failure data stored in the memory of each • Key Switch
controller. • Body Seated
• Body Float
• Rear Brake
• Service Brake
2. EXPLANATION OF SELF-DIAGNOSTIC • Emergency Brake
DISPLAY FUNCTIONS • Tilt
Each controller is equipped with a self-diagnostic trou- Relay:
bleshooting display function, so if any electrical abnor- • Engine Heater for start
mality (disconnection, short circuit, internal short, or
short circuit between wires, etc.) occurs in output or
input signals, or there is input or output that does not
match the operation of the truck, the nature of the
abnormality is displayed.

Data that is displayed
• Troubleshooting information
• Action code
• Caution signal
• Transmission failure codes
• Alarm buzzer
• Suspension failure codes
(optional)
• Engine speed
• Truck speed (transmission,
Network Data output may p/u)
• Power mode
• Shift lever position
• Shift indicator
• Lock-up ON/OFF
• Shift limit
• Air pressure
• Retarder oil temp.
• Engine coolant temp.
• Transmission torque converter
temperature
• Retarder oil temp.
• Engine oil pressure
• Transmission oil filter
• Fuel level
• Parking brake ON/OFF
• Rear brake ON/OFF
• Body float
• Exhaust brake (optional)
• Lateral inclination
• Emergency steering
• Body seat switch
• Alternator. "R"
• Key Sw. "C" terminal
• Brake stroke Switch
FIGURE 4-28. MONITOR PANEL

3. CHECKING OPERATION OF ELECTRICAL SYSTEM
When a sequence of operations is carried out using the procedure below, and if the monitor panel, transmission
controller, suspension controller, and payload meter controller perform the actions given below, it means that the
input and output signals, the monitor panel that the controllers are operating normally.
Perform the actuation check with the truck unloaded. (The actuation of the suspension controller (if equipped) differs
when the truck is loaded or unloaded, but it is possible to check all of the mode selections with the truck unloaded.)
Sequence of operations and Check items (when normal)

condition on truck Monitor panel Engine controller Transmission controller Suspension controller optional
(1) Turn starting switch OFF All OFF All OFF All OFF All OFF
Monitor panel liquid
Turn starting switch to ACC crystal display lights 8.8 is displayed for 3
up seconds
Suspension mode Self-diagnostic display
* Parked: only with parking lights up for 4.2
soft portion light up
brake seconds, then goes
(optional)
out, and details of past
Caution, pilot lamps failures are displayed
* Bulb check switch ON
all light up for 3 seconds each.
(2) * Power mode selection switch- * Power mode After that, if the
"OFF" display condition is normal, 0.0
* Power mode switch-"ON" Economy/high or 0.c (in cold weather)
switch light "ON" power lights up is displayed.
Shift limiter liquid
* Shift limiter switch ON/OFF crystal display lights
up/goes out
Shift indicator N
* Shift lever set to N * Shift position 2-digit LED displays 0.0 (normal)
display N
* Engine speed is
Start engine When transmission oil
displayed
* If water temperature is below temperature is below
* On cooling water Engine speed
40°C (105°F) automatic 10°, 0.0 is displayed
temperature 1000 rpm
warming-up operation is
(3) display, only lowest
actuated
segment lights up
* IF water temp is above 70°C When water temp When oil temperature
Engine speed:
(160°F) after completion of display is in green is below 10°, 0.0 is
650 rpm
warming-up operation range displayed
Engine speed rises
Parking lamp goes
out
Release parking brake and Rear brake lamp Engine speed:
apply the service brake only lights up 1000 rpm
Suspension mode
(4) display (if equipped)
Soft-medium
* Rear brake lamp
lights up
Release service brake and pull Engine speed: Suspension mode switched
* Suspension mode
retarder lever 1000 rpm Soft-medium
soft portion lights up
(if equipped)

Check items (when normal)
PMC controller (If equipped) Payload meter controller (If equipped)
(1) All OFF All OFF
0.box (box:a-d) is display for 1 second
(2) 8.8,8.8 display, external display lamps all light up
After that, if the condition is normal, the display changes to 0.0
Buzzer sounds for 3 seconds
* Engine speed: 1,000 rpm
(3) 9 items, such as payload meter switch settings, are displayed for
* Engine speed: 650 rpm 3 seconds each.
* Engine speed: 1,000 rpm After that, payload display is given
(4)
* Engine speed: 1000 rpm
(5) If condition is normal, 0.0 is displayed b-FL display, buzzer sounds

Check Items (when normal)
Sequence of operations and condition
ON truck Transmission Suspension
Monitor Panel Engine Controller
Controller Controller (Optional)
(7) Lower body, release parking
brake, then set shift lever to L
and travel forward Shift indicator 1 Travel speed range
Release brake Shift position display L F1-F2 Suspension mode
After truck moves off, press selection
accelerator pedal Hard -> soft
Shift limiter switch ON Shift limiter function
Switch light ON Shift indicator display 1/1-2 actuated F1
Shift limiter switch OFF fixed/shifts up to F2
(8) Shift indicator 3
Set shift lever to D and shift up Travel speed range
Shift position display D
to F3 or above F2-F7
Lock-up liquid crystal display
Exhaust brake is
Turn exhaust brake switch
actuated even Suspension mode
(EXH. BRAKE) ON and release
when retarder lever selection
accelerator pedal
is not actuated Hard - Soft
Turn exhaust brake switch
(EXH. BRAKE) OFF and release Change in exhaust
accelerator pedal/Release brake logic
accelerator peedal and operate Not actuated
retarder lever
(9) Check Lock-up function Monitor Panel Transmission Controller

Lock-up is not actuated when
Set shift lever to R Lock-up display does not light up
traveling in reverse
Set shift lever to D or 5 - L Lock-up range is F! - F7
Set to F1 or F2, release accelerator pedal, and
(1) Lock-up display does not light up Lock-up is actuated
move truck without operating brake
(2) Engine speed 1500 rpm
Lock-up display lights up Lock-up is actuated
or more
Depress accelerator Engine speed 1200 rpm

Lock-up display does not light up Lock-up is not actuated
pedal or operate brake or less
After Switching shift indicator
Shift gear display, lock-up display goes out Lock-up is canceled when shifing gear
temporarily
(3) Lock-up display stays lighted up Shifts down F7 - F6, F4-F3 with the
Release accelerator
until shift indicator display is 4 lock-up still engaged.
pedal and do not Shift down
Lock-up display stays out after For F3 and down, transmission shifts
operate brake
shift indicator display becomes 3 down without engaging lock-up.

NOTES:

MONITOR PANEL ACTION CODES AND SERVICE MODE
OUTLINE
If a failure is detected when the monitor panel is in the The displays (Figure 4-29 & 4-30) are repeated in turn
normal mode, the lamp or caution display for the for 1 second each.
applicable location lights up and an action code is
However, if a new fault occurs, data is sent while the
displayed according to the failure to aid the operator in
action code is being displayed and the action code for
taking suitable action. When an action code is dis-
the new fault has priority over the existing action code
played, the operator should follow the recommended
being displayed. The display will change to the new
action, and should also follow the Operation and Main-
action code. If the new code has a low priority, the
tenance Manual to display the service codes on the
display stays unchanged. In other words, the action
monitor panel to check the cause of the action code.
code with the highest priority is always displayed.
In addition, to make troubleshooting easier, there is a
There are seven types of action code from 01 to 07.
service mode on the monitor panel. This can display
(A decal is stuck to the top left of the window glass at
trouble data saved in the memory of the controllers on
the front of the cab to tell the operator what action to
the network and display the recognized values for the
be taken when a fault occurs). If an action code is
input and output signals from each controller.
displayed, have the operator check the service code
for the fault and then have him inform the service
ACTION CODE DISPLAY
department.
If any controller on the network detects a fault, the While the action code is being displayed, if lamp check
controller LED display panel will show the fault. The switch (1) is pressed for at least 2.5 seconds and then
monitor panel displays an action code according to the released, the applicable service code is displayed. If
fault transmitted to the network, and continues to dis- more than one fault has occurred, each fault is dis-
play it until the condition is corrected. played in turn for 3 seconds, and when all of the service
codes have been displayed, the system returns auto-
matically to the action code display.
FIGURE 4-29. DISPLAYING OCCURRENCE OF

AN ERROR (E-) FIGURE 4-30. DISPLAYING ACTION CODE (03)
FIGURE 4-31. SERVICE CODE FOR EXISTING FAILURE IS (A111)
D04009 Introduction of Electrical Troubleshooting D4-39

SERVICE MODE When engine speed recognized by transmission con-
troller is being monitored (Figure 4-32).
The service mode is used when it is desired to know
the service codes for existing failures or failures that
have occurred in the past. Also to monitor the values
recognized for the signals from the controllers.
1. The service mode contains the following:

A) Service codes, (this mode displays the fault
occurrence data as well as faults saved in the
memory of the controllers on the network)
B) Truck data monitoring mode: (this mode dis-
plays the values for the inputs and outputs
recognized by the controller on the network)
The modes are switched by using the mode change FIGURE 4-32. MONITOR DISPLAYS
switchs. IF the key switch is turned "OFF" when there
1. This is a "b" which is the service code for the
is a service code displayed, it is possible to start again
transmission.
from the normal mode after the key switch is turned
2. This is the monitoring code which is the engine
"ON". If the monitor panel or other controllers detect a
speed. "05"
fault while in the service mode, the system automat-
3. The display is in units of 10 rpm, so the display
ically returns to the normal mode and displays the
means 2,050 rpm.
action code.
2. Truck data value monitoring mode

a. For the list of items that can be monitored by
the controllers, chart - Monitoring Items In
Truck Data Value Monitoring Mode (page D4- When switch input condition recognized by transmis-
49). sion controller is being monitored (Figure 4-33).
b. The order for displaying the controllers de-
pends on the order of the controller code (*1),
but controllers that are options and are not
installed are automatically omitted and are not
displayed.
For details of the method of operation, Method Of

Operating Service Mode (page D4-44). This is the
mode to display the input values of the sensors and
switches recognized by the controllers, and the output
values of the controllers. Each controller can monitor
up to several switch and sensor input values and
electric current or other output values.
FIGURE 4-33. MONITOR DISPLAYS
1. This is a "b" which is the service code for the
transmission.
2. This is the monitoring code which is for
"switch check"
3. Bit 1 and bit 13 in item 3 are ON. This means
that the body seated switch is ON (seated)
and model selection signal 4 is ON (GND).
NOTE: Refer to Figure 4-45 for bit number
assignments.
D4-40 Introduction of Electrical Troubleshooting D04009

c. The controller code and monitor code are dis- In the same way as with the truck data value monitoring
played for one second each. code, the order for displaying the controllers depends
d. For details of the truck data value monitoring on the order of the controller code, but controllers that
mode and method of proceeding (going back) are options and are not installed are automatically
with the monitor items, see table 1 methods of omitted.
operating switches. A. Display of elapsed time since the code was deleted.
Controller codes: 1. Content of display
A: Monitor panel * The display shows the time elapsed (service meter
reading) since the latest trouble data item was
b: Transmission controller deleted form memory. For details of the method
d: Suspension controller (optional) of deletion, see Method of Deleting Trouble Data
From Memory, (Page D4-48).
e: PMC (optional)
2. Display timing
f: Payload meter II (PLMII) (optional)
* Immediately the system enters the service code
To make it possible to display the controller code with and trouble data display mode, the display is
the 7-segment LED, uppercase and lower case letters given once only and it then goes automatically to
are used. the next service code and trouble data display.
3. Service code and trouble data display mode

For details of the method of operation, see Method Of Figure 4-34 DELETE display (2 seconds)
Operating Service Mode (page D4-44). Figure 4-35 The time elapsed (101h) since the last
This mode displays the time elapsed since the deletion deletion is displayed (2 seconds)
operation, and gives the service code and trouble data
display. With the service code and trouble data dis- NOTE: When the deletion operation is carried out, the
play, the service code is displayed for each controller elapsed time is reset and starts again from 0. If neces-
for faults that currently exist and faults that occurred in sary, note down the elapsed time before deleting any
the past which have been repaired. item.


4. Service code and trouble data display
Details of display E. Order of display
A . The following trouble data (1) - (4) are displayed (1) The four items under "A" above are displayed
for each controller and each service code. in order for each controller.
(1) Service code (the controller code explained (2) Data for currently existing fault (service mode,
above (A,b,c,.....) + 3 digit number (fault) elapsed time (1), elapsed time (2), number of
occurrences) inside the same controller are
(2) Elapsed time 1 (elapsed time (service meter
displayed first, then data for faults that have
reading) since that failure first occurred)
already been repaired are displayed.
(3) Elapsed time 2 (elapsed time (service meter
(3) For faults that are currently existing and faults
reading) since that failure last occurred)
that have already been corrected, the data is
(4) Number of occurrences (the number of times displayed in turn, starting for each type from the
that the fault has occurred) failure that occurred most recently (the small-
B. When the data for a fault that is currently existing, est value for elapsed time (2)).
the high beam pilot light comes "ON". * Example of order of display
C. Unless the display is changed by operating the When the trouble data in the memory of one of the
switch, the above four items will continue to be controllers is as follows:
displayed. For details of the method of operating Service code A111 A121 A131 A141
the switch, see Method of operating service Elapsed time 5 2 6 12
mode.
Existing
D. If there is no trouble data, or it has all been /corrected Existing corrected existing corrected
deleted, -- is displayed.
The data are displayed in order according to above for
1. Only for the trouble data display for the suspen-
each controller.
sion controller (controller code: d), the above
elapsed time is displayed as --.

If high beam pilot lamp (1, Figure 4-36) lights up, this The displays (shown in figures 4-36 thru 4-39) are
shows that the trouble data is for a currently existing displayed repeatedly in turn for 2 seconds each.
fault.
NOTE: After displaying Figure 4-39, the display returns
If high beam pilot lamp (1, Figure 4-36) is out, this to Figure 4-36
shows that the trouble data is for a fault that has been
* For details of the service code, see TABLE OF
corrected.
SERVICE CODES AND ACTION CODES
FIGURE 4-36. SERVICE CODE (A111) FIGURE 4-39. FAULT OCCURRENCES

Shows that A111 currently exists. Shows that within a period of 1151h, this fault
occurred 3 times.
FIGURE 4-37. FIRST FAULT OCCURED FIGURE 4-38. LAST FAULT OCCURED
This shows that the fault first occured 1151h Shows that the fault last occurred 1h ago.
ago.

5. Method of Operating Service Mode IF a fault with a action code of a lower priority than the
action code being displayed, even when the Operation
* A summary is given in Table 1 " Methods of Operating
A is carried out, the action code will not go out, but the
Switches".
display will change to the code with the lower priority.
The service mode is operated by using the mode In addition, even if a fault with the same action code
change switches at the left side the dashboard, next has occurred several times, Operation A must be
to steering column. carried out the same number of times as the number
of occurrences for the action code display go out.
There are two mode change switches, (1) and (2) :
If Operation A is carried out, it is possible to enter the
Switch (1) toward the front of the truck ("red color") truck data monitoring mode.
Switch (2) is toward the rear of the truck ("black color").
NOTE: The numbers are on the switch box, so check
the switch box.
To operated the mode change switches, move the

switch to the right for the "ON" position; when the
switch is released, it will automatically return to the
OFF position.
Operation A: Method of entering service mode
method of switching mode (see table 1)
Operate both mode change switches (1) and (2) to the
ON position at the same time for at least 0.2 seconds
(but not more than 2.5 seconds). Then release to the
"OFF" position. This will switch to the truck data moni-
toring mode. To switch the mode, actuate the switches
again. This displays elapse time, service mode and
trouble data mode. Operate the switches again, the
FIGURE 4-40. SWITCH LOCATIONS
display will return to normal mode.
* For details of Operation A, see the Table 1: Methods
of operating switches.
Note: In the normal mode, if a fault currently exists, and
the action code for that fault is displayed, and Opera-
tion A is carried out, the action code will go out.
FIGURE 4-41. CHANGE IN SERVICE MODE

Operation B: Method of changing display in truck data Operation C: Method of changing display items in
monitoring mode service code and trouble data display mode
• When the system enters the truck data monitoring mode, it • When the system enters the service code and trouble data
automatically displays first standard service meter on the moni- display mode, it first displays the elapsed time since the latest
tor panel (controller code: A). deletion (see page D4-48). Then it automatically displays the
first item of trouble data on the monitor panel (controller code:
• To go on to the next display, press the mode change switch (1)
A).
to the "ON" position for 0.2 - 2.5 seconds, then "OFF". (When
switch is released , it will return automatically to the OFF • If there is no trouble data in the monitor panel memory, -- is
position). (Operation B) displayed.
• To go back to the previous item, press mode change switch (2) • To go on to the next item, press the switch (1) to the "ON"
to the ON position for 0.2 - 2.5 seconds, then "OFF". (When it position for 0.2 - 2.5 seconds, then OFF. (When it is released,
is released, it will return automatically to the OFF position). it will return automatically to the OFF position). (Operation B)
(Operation D)
• To go back to the previous item, mode change switch (2)
• After pressing mode change switch (1) to the "ON" position for pressed to the ON position for 0.2 - 2.5 seconds, then OFF.
at least 2.5 seconds, turn it OFF. (When it is released, it will (When it is released, it will return automatically to the OFF
return automatically to the "OFF" position). (Operation C) The position). (Operation D)
system will then move to the next controller and display the first
• After pressing mode change switch (1) to the ON position for
item.
at least 2.5 seconds, then OFF. (When it is released, it will
• After keeping mode change switch (2) pressed to the ON return automatically to the OFF position). (Operation C) The
position for at least 2.5 seconds, then OFF. (When it is re- system will then move to the previous controller and display
leased, it will return automatically to the OFF position). (Opera- the first item of data.
tion E) The system will then move to the previous controller and
• Press the mode change switch (2) to the ON position for at least
display the first item.
2.5 seconds, then OFF. (When it is released, it will return
• For reference, see the following diagram showing the cycle of automatically to the OFF position). (Operation E) The system
operation. will then move to the previous controller and display the first
item of data.
TABLE 1. METHODS OF OPERATING SWITCHES

FIGURE 4-42. METHODS OF OPERATING SWITCHES

Checking that fill signal for 2nd clutch is
correctly recognized by transmission controller
Operation of machine Operation of mode change switch Monitor panel display

Normal mode is displayed after 3 seconds
Turn starting switch ON
Normal mode remains displayed
Start engine
Operation A Monitor panel item code 1 (standard service meter) of truck
(Switch mode and enter service mode) data monitoring mode is displayed
Operation C Transmission controller item code 1 (model recognition) of

(Go to next controller) machine data monitoring mode is displayed
Operation B Transmission controller item code 2 (service meter) of truck

(Go to next item code) data monitoring mode is displayed
Operation B Transmission controller item code 3 (switch check) of truck

Operation B Transmission controller item code 4 (fill signal check) of truck

Shift to F2. L clutch (bit No. 1, Figure 4-43) and 2nd clutch (bit
Check that parking brake and
No. 5) are engaged and applicable portion lights up
retarder brake are applied, then
operate shift lever to D position
L clutch (bit No. 1 ) and 2nd clutch (bit No. 5) are disengaged
Return shift lever to N position
and applicable portion goes out
Operation A After elapsed time since deletion operation is displayed (2

(Switch mode and enter service code, seconds), displays item 1 of transmission controller trouble
trouble data display mode) data in service code, trouble data display mode
Operation A Displays normal mode

(Switch mode and return to normal
mode)
• At any stage in the above process, if the key

switch is turned OFF, and then ON again, the
monitor panel will return to the normal display.
• While the system is in the service mode, if the
monitor panel or other controller detects a fault,
the system will automatically return to the nor-
mal mode and display the action code.
FIGURE 4-43. DISPLAY MESSAGE

Method of deleting trouble data from memory Precautions when operating service mode
In the service code and trouble data display mode, it 1. When deleting the trouble data from memory, if
is possible to delete the displayed trouble data from mode change switches (1) and (2) are not kept
memory. However, the data for currently existing prob- pressed to the "ON" position at the same time for
lems cannot be deleted. at least 5 seconds, the monitor panel will judge
that it is Operation A and the system will return to
Method Of Deletion
the normal mode without deleting the data form
1. Enter the service code and trouble data display memory.
mode, and display the trouble data that is to be
If the data is deleted correctly, the system will
deleted.
automatically switch to the next trouble data dis-
2. Press mode change switches (1) and (2) to the play, so the deletion operation can be checked. If
ON position at the same time for at least 5 sec- all the trouble data inside the controller is deleted,
onds, then off (Operation F). " --" is displayed, so the completion of the deletion
operation can be checked.
3. The display trouble data will be deleted from
memory and the display will automatically switch 2. If you enter the service mode or operate mode
to the next trouble data. change switch (1) or (2) in order to switch some-
thing in the service mode, if it overlaps the timing
NOTE: When the deletion operation is carried out, the
of detection of occurrence or restoration of fault
elapsed time is reset and starts again from 0, so it may
on the monitor panel or controllers, it may take
be necessary to note the elapsed time before deleting
time for the service mode display to switch. In
any item.
such cases, return to the normal mode and try
again.
FIGURE 4-44. MODE SWITCHES

3.5 Monitoring items in truck data monitoring mode
* For details of the method for going on to the next monitor item (or going back to the previous monitor item) in the
truck data monitoring mode, see Method of operating service mode.
Contro Monitor
Item Display unit Remarks
ller code item code
Monitor Panel
After 10000h, shows units of 100h, and left turn signal
1 Standard service meter 10h
lamp lights up
The 1), 2), etc. in the item corresponds to the bit number.
Switch check
When ON, applicable bit number lights up, See Table 1
1) KPH/MPH selector signal ON/OFF ON: mph displayed
A 2 2) Exhaust brake switch (optional) ON/OFF Only when exhaust brake is installed
3) AISS switch ON/OFF
4) Mode selector switch 1 ON/OFF
5) Mode selector switch 2 ON/OFF
0 - 9 stay as they are, A - F are replaced with 10 - 15,
3 Rotary switch setting 0 - F level
applicable number in Table 1 lights up
Transmission Controller
1 Model recognition See Table 2 (*2)
For details, see item 3) Service meter for each controller
2 Service meter 10h After 1000h, shows units of 100h, and left turn signal lamp
lights up
Switch check
When ON applicable bit number lights up. See Table 1
1) Body seated switch ON/OFF ON: When seated
2) Not used
3) Not used
4) Not used
5) Not used
6) Not used
3 7) Not used ON/OFF
8) Not used
9) BCV solenoid ON/OFF
10) Model selection signal 1 ON/OFF ON : GND.
B
14) Connector check 1 ON/OFF ON : GND.
15) Connector check 2 ON/OFF ON : GND.
16) Emergency escape switch ON/OFF
17) Starting switch ON/OFF
Fill signal switch
When ON applicable bit number lights up. See Table 1
1) L clutch ON/OFF
2) Not used ON/OFF
4 3) H clutch ON/OFF
4) 1st clutch ON/OFF
5) 2nd clutch ON/OFF
6) 3rd clutch ON/OFF
7) 4th clutch ON/OFF
8) R clutch ON/OFF
5 Engine speed 10 rpm
6 Transmission input shaft speed 10 rpm
7 Transmission intermediate shaft speed 10 rpm

Contro Monitor
Item Display unit Remarks
ller code item code
Transmission Controller
8 Transmission output shaft speed 10 rpm
9 Accelerator sensor 0.02V
10 Brake air pressure See Table 3
11 Not used
12 Rear brake cooling oil temperature 1°C Lo display when less than 60° C, see Table 4
13 Not used
14 Not used
15 Torque converter outlet port oil temp 1° C Lo display when less than 60° C, see Table 4
16 Fuel Level 1Ω
17 Not used
18 ECMV oil temperature 1° C Lo display when less than 60° C, see Table 4
19 Not used
B
20 Not used
21 Not used
22 Not used
23 Max. Speed range 4-7 4 - 7: F4 - F7 (no limit)
1 - 3: F1 - F3, 0: default (F2 only when lever is at D, F1 only when
24 Max. Speed range (when body is raised) 0-3
lever is at position other than D)
25 Caution setting (when body is raised) 1 or 2 1: OFF, 2: ON
26 Spare
27 Solenoid H output 4 mmA
28 Solenoid L output 4 mmA
29 Solenoid 1 output 4 mmA
33 Spare
34 Spare
Suspension Controller (Optional)
For details, see item 3) Service meter for each controller (5) After
1 Service meter 10h
10000h, shows units of 100h, and left turn signal lamp lights up
Switch check
When ON, applicable bit number lights up, See Table 1
1) Auto suspension solenoid 1 output ON/OFF
2 2) Auto suspension solenoid 2 output ON/OFF
3) Auto suspension solenoid 3 output ON/OFF Transmission output shaft speed
4) Rear brake ON/OFF
C 5) Body FLOAT switch ON/OFF ON: GND (when not at FLOAT position)
6) Body selection awitch ON/OFF ON: GND (HD465) OFF: OPEN (HD605)
3 Suspension pressure (left) {1kg/cm}
4 Suspension pressure (right) {1kg/cm}
5 Steering angle speed
6 Spare
7 Spare
8 Spare
9 Spare
10 Spare
11 Transmission output shaft speed 10 rpm

Table 1 Bit numbers (Refer to Figure 4-45) TABLE 2 - CONTROLLER MODEL RECOGNITION
When it is difficult to judge which bit number is lighted Machine data monitoring mode
Machine specification
up (in particular, numbers 3 and 8 or 5 and 14), it is model display value
possible to press the lamp check switch (1, Figure 330 330 M Electric governor
4-46) to light up all the segments and check the bit 33A
330 M Electric governor, ABS
position. installed (ABS is an option)
FIGURE 4-45. BIT NUMBER LOCATIONS
FIGURE 4-46. DISPLAY PANEL

1. Lamp Check Switch

BRAKE AIR PRESSURE SENSOR
Pressure display of brake air pressure sensor.
The brake air pressure sensor is not an analog output
but a level output, so the value for the pressure display
corresponds to the air pressure in table 3 below.
TABLE 3 - BRAKE AIR PRESSURE SENSOR

Pressure display value in truck data monitoring mode MPa {kg/cm}
Caution level Gauge level
When pressure is rising and at present level When pressure is rising and at present level
Red 7 0.932 {9.5}
Green 6 0.814 {8.3} 0.912 {9.3}
Green 5 0.716 {7.3} 0.794 {8.1}
Green 4 0.618 {6.3} 0.696 {7.1}
Green 3 0.510 {5.2} 0.598 {6.1}
Red 2 0.245 {2.5} 0.510 {5.2}
Example of display (torque converter outlet port oil

temperature) Figure 4-47.
This shows that item code 15 (torque converter outlet
port oil temperature) on the transmission controller
(controller code b) is below 60°C.
Note: Service meter for each controller. The service
meter holds individual values for each controller and
those values are displayed. However, basically, the
values are the same for all controllers. However, if the
controller is replaced with a new controller, the service
meter for that controller will have lower values than the
other controllers.
In such cases, the service meter used for the time of
occurrence of a trouble data display is standardized as
the standard time for the network system (service
meter on the monitor panel). Therefore, even if a
controller is replaced with a new part, when the failure
FIGURE 4-47. MONITOR DISPLAY
detected by the controller is displayed, the service
meter display is the standard time for the network
system, so there is no difference from the other con-
trollers.

SELF-DIAGNOSTIC DISPLAY METHOD FOR MONITOR PANEL AND
CONTROLLERS
For details of the display on the monitor panel, see Monitor panel action code and service mode function.
MONITOR PANEL
After the starting switch is turned ON, the monitor itself carries out self-diagnosis. After that, it goes to the normal
display.
Check the bulbs of the pilot and caution lamps by pressing the lamp check switch at the right edge of the panel.
For details of the service codes, see SERVICE CODE TABLE.
1. Self-diagnostic display, warning display
The content of the self-diagnosis and warning is displayed by a 2-digit LED code.
If any abnormality is detected during self-diagnosis, the fault occurrence data is sent to the network and the action
code is displayed on the monitor panel. The electronic controller display on the monitor panel may also light up. The
warning lamp and buzzer may also be actuated.
The warning display is the detection of a fault in the pilot lamp display sensor systems and warnings and warning
actuations. If problems are detected, the warning lamp and buzzer may also be actuated.
Self-diagnostic Display Code Table

Abnormal system Display code Action of controller Action to be taken
0.1, d.A
Defective controller power source system A 1
0.2, d.b
Neutral safety 0.3 A 1
0.4
Defective controller system A 1
0.5
Defective transmission cut relay system 0.6 A 1
Defective rear brake solenoid system 0.8 B
Defective exhaust brake solenoid system 0.9 B 2
Defective BCV rear solenoid system C.4, C.6, C.8 B 1
Defective engine speed sensor system 1.0, 6.0 C 3
Defective transmission input shaft speed sensor system 1.1, 6.1 C 1
Defective transmission intermediate shaft speed sensor
1.2, 6.2 C 4
system
Defective transmission output shaft speed sensor system 1.3, 6.3 C 1
Clutch slipping or defective speed sensor system 2. ←2-8 D 4
Defective model selection signal system 1.4, A.1S E 1
0.7
Defective shift lever system 1.5 B 5
1.6
Defective accelerator sensor system 1.7 B 1
Defective transmission valve oil temperature sensor system 1.9 B 1
3. ←2-8
Defective pressure control valve system
4. ←2-8 D 4
Defective oil flow control valve system 5. ← 2 - 8 C 4

7. ← 1 - 8 E
9. ← 1 - 8
Defective pressure control solenoid system 4
B
A.2, A.3
Defective monitor panel display sensor system [b2,b7 are
b.3, b.4 B 1
for mechanical governor specification machine only]
b.2, b.7
Mistaken connector connection C.1 E 1

Warning Display Table
Action of Action to be
Abnormal system Display code
controller taken
Pilot lamp warning
Transmission filter clogging d.1 F 6
Tilt warning d.5 F 6
Drop in radiator water level d.6 F 6
Battery charge d.7 F 6
Steering oil level (overheating) E.5 F 6
Drop in rear brake oil pressure F.6 F 6
Actuation warning
Engine overrun actuated d.8 F -
Engine overrun short circuit actuated d.9 F -
Overheat warning
Torque converter oil temperature d.2 F -
Retarder oil temperature d.3 F -
Pressure drop warning
Drop in air pressure d.9 F -
Explanation of symbols: [ ] 1 - 8: indicates that there are display patterns from 1 to 8 that appear in the [ ] portion.
1. : Lock - up clutch related parts
2. : H clutch related parts
3. : L clutch related parts
4. : 1st clutch related parts
5. : 2nd clutch related parts
6. : 3rd clutch related parts
7. : 4th clutch related
8. : R clutch related parts
|_| : Blank (no display)
NOTE: See the next page for explanation of the symbols used in the action of controller column.

Method of re-enacting fault displayed (Action to be taken).
Using the following procedure, it is possible to re-enact the fault and carry out inspection.
1 Turn the key switch OFF - ON.
5 Turn the key switch OFF - ON, and operate the lever slowly in turn to N, R, N, D, 5, 4, 3, L.
(Stop for at least 3 seconds at each position, then go to the next position).
3 Set the lever to N and start the engine.
4 Use the clutch specified in the fault display (set to the speed range using that clutch) and carry out
a trouble test.
Display Applicable clutch Speed range

Either 7 or 9

(inside ) 1. Lock - up clutch L/U
2. H clutch F3, F5, F7
3. L clutch F1, F2, F4, F6
4. 1st clutch F1
One of 2, 3, 4, 5, 7, 9 5. 2nd clutch F2, F3

(inside ) 6. 3rd clutch F4, F3
7. 4th clutch F6, F7
8. R clutch R
- (intermediate shaft
1.2 F2
sensor)
2 Apply exhaust brake during travel test. (When traveling in lock - up, operate the exhaust brake switch
then the accelerator released)
6 If there is a fault in the sensor system, turn the key switch OFF - ON.
Operation of controller when fault is detected (Action of Controller)

If an fault is detected, the transmission controller displays the fault and carries out the following action.
A Transmission neutral . . . . . . . . . . there is a fault in the power source or controller, so the transmission is
set to neutral.
E Transmission neutral . . . . . . . . . . the electrical system for the truck and the controller may have failed,
so the controller automatically turns the output OFF.
D Transmission neutral . . . . . . . . . . there is probably a fault in the hydraulic or mechanical part of the
transmission, so to avoid fatal damage to the transmission,
the controller automatically turns the output OFF.
C Speed range held, . . . . . . . . . . because of a fault condition, the controller judges it is impossible to shift
but when lever is gear, so it holds the gear range.
moved to N, N is held
B Travel possible, . . . . . . . . . . . the controller automatically stops the functions in the faulty system.
but some functions
are inoperative -
F Travel possible . . . . . . . . . . . . . . the controller works normally

2. Transmission mode display
The transmission controller always displays if the transmission is being controlled in the normal temperature mode
or in the low temperature mode.
Transmission mode display

When normal When abnormality is detected
Normal temperature mode 0.0 After E. |_| is displayed, code is displayed to show a fault
Low temperature mode 0.C After E.C is displayed, code is displayed to show a fault
3. Saving self-diagnostic display to memory

Once an fault is detected, even if the fault is removed, self-diagnostic display remains displayed for 5 minutes.
NOTE: The action code display on the monitor panel, the electronic controller display, warning lamp, and buzzer stop
when the fault is removed.
NOTE: Even when two or more faults occur at the same time, all the fault occurrence data are transmitted to the
network and the self-diagnostic display is given.
Display method: The code display starts with the faults that have occurred in order, and after completing the display
of the content of all the faults, the display returns to the first code display. It continues to repeat this order. If the fault
is repaired, it returns to the normal display 5 minutes after the repair.

4. Saving service code to memory
The transmission controller has a function to save the service code, time of occurrence (service data) and number
of occurrences to memory, and keep them in memory even after the starting switch is turned OFF.
When the key switch is turned ON, it is possible to check the details of the faults that have occurred up to that point
with the trouble data display mode of the monitor panel service function and the controller LED’s.
Method of saving and displaying service code (transmission controller LED display)
FIGURE 4-48. TRANSMISSION CONTROLLER DISPLAY
To make full use of the memory function to clearly display when the failure occurred and what failures have already
been corrected, keep strictly to the procedure given below.
Deleting service code from memory
For details of the method of deletion, see Method of deleting trouble data from memory (page D4-48)
Carry out troubleshooting, and when the fault has been repaired, the self-diagnostic display returned to normal, to
delete the transmission controller service codes from memory, turn the starting switch OFF, then turn it ON again,
and check the past faults in memory have been deleted
For details, see MONITOR PANEL ACTION CODES AND SERVICE MODE FUNCTION, Method of deleting trouble
data from memory.
(if the data have been deleted, 8.8 is displayed for 3 seconds, then the display shows the part number, and after 3.5
seconds, the display returns to the normal display of 0.0 or 0.C)

TABLE OF SERVICE CODES AND ACTION CODES
1. TABLE OF SERVICE CODES AND ACTION CODES RELATED TO MONITOR PANEL
TABLE OF SERVICE CODES AND ACTION CODES RELATED TO MONITOR PANEL

Monitor panel display
Service code
When only lamp Central
Display in caution
No. Details of failure check switch is kept Action warning
service code, lamp
pressed for at least lamp
trouble data
2.5 sec and then
display mode
released
(Existing) (Existing) (Existing) (Existing) (Existing)
1 Short circuit in lamp output system A001 A000 02 ON OFF
2 Short circuit in central warning lamp output system A002 A000 02 ON OFF
3 Short circuit in alarm buzzer output system A003 A000 02 ON OFF
Connection data for network system does not
4 A012 A011 02 ON ON
match
5 Fault in network system (transmission controller) A013 A011 02 ON OFF
6 Fault in network system (PMC) (optional) A014 A011 02 ON ON
7 Fault in network system (engine controller) A015 A011 02 ON ON
8 Fault in network system (suspension controller) A016 A011 02 ON ON
9 Fault in model selection data A018 A011 04 ON ON
10 Fault in option data A019 A011 04 ON ON
Note 1: "Existing" means that the problem is still occurring; "history" means that the problem occurred in the past.
Note 2: If the problem is still existing, the alarm buzzer will also sound. (When the central warning lamp is ON).

2. TABLE OF SERVICE CODES AND ACTION CODES RELATED TO TRANSMISSION CONTROLLER
Table Of Service Codes And Action Codes Related To Transmission Controller

Automatic Transmission oil
gear Central temperature
Service Action
No. Details of failure shifting warning 15° C Below
code code
caution lamp (60 ° F) 15° C
lamp or above (60 ° F)
(Existing,
(Existing) (Existing) (Existing) (Existing) (Existing (History)
reset)
1 Fault in battery power source voltage system b001 04 ON ON E. ↔ 01 EC ↔ 01 01
2 Fault in solenoid power source system b002 04 ON ON E. ↔ 02 EC ↔ 02 02
3 Fault in neutral safety system b003 - ON ON E. ↔ 03 EC ↔ 03 03
4 Double engagement of clutches b005 04 ON ON E. ↔ 05 EC ↔ 05 05
5 Fault in transmission cut relay b006 04 ON ON E. ↔ 06 EC ↔ 06 06
6 Fault in shift lever assembly power source (12V) b007 04 ON ON E. ↔ 07 EC ↔ 07 07
7 Fault in engine overrun solenoid system b008 02 ON ON E. ↔ 08 EC ↔ 08 08
8 Fault in exhaust brake solenoid system b009 02 ON ON E. ↔ 09 EC ↔ 09 09
9 Disconnection in engine speed sensor system b010 02 ON ON E. ↔ 10 EC ↔ 10 10
Disconnection in transmission input shaft speed
10 b011 02 ON ON E. ↔ 11 EC ↔ 11 11
sensor
Disconnection in transmission intermediate shaft
11 b012 02 ON ON E. ↔ 12 EC ↔ 12 12
speed sensor system
Disconnection in transmission output shaft speed
12 b013 02 ON ON E. ↔ 13 EC ↔ 13 13
sensor system
13 Fault in model selection signal system b014 04 ON ON E. ↔ 14 EC ↔ 14 14
14 Multiple input of shift lever signal b015 02 ON ON E. ↔ 15 EC ↔ 15 15
15 Disconnection in shift lever signal b016 02 ON ON E. ↔ 16 EC ↔ 16 16
16 Fault in accelerator signal b017 02 ON ON E. ↔ 17 EC ↔ 17 17
Fault in transmission valve oil temperature sensor
17 b019 02 ON ON E. ↔ 19 EC ↔ 19 19
system
18 Fault in H clutch system b022 02 ON ON E. ↔ 22 EC ↔ 22 22
19 Fault in L clutch system b023 02 ON ON E. ↔ 23 EC ↔ 23 23
20 Fault in 1st clutch system b024 02 ON ON E. ↔ 24 EC ↔ 24 24
21 Fault in 2nd clutch system b025 02 ON ON E. ↔ 25 EC ↔ 25 25
22 Fault in 3rd clutch system b026 02 ON ON E. ↔ 26 EC ↔ 26 26
23 Fault in 4th clutch system b027 02 ON ON E. ↔ 27 EC ↔ 27 27
24 Fault in R clutch system b028 02 ON ON E. ↔ 28 EC ↔ 28 28
25 Fault 1 in pressure control valve system for H clutch b032 02 ON ON E. ↔ 32 EC ↔ 32 32
26 Fault 1 in pressure control valve system for L clutch bo33 02 ON ON E. ↔ 33 EC ↔ 33 33

Table Of Service Codes And Action Codes Related To Transmission Controller (Continued)
Monitor panel display Controller LED display
gearshiftin Central temperature
Service Action
No. Details of faulure g warning 15° Below
code code
caution lamp (60 ° F) 15°
(Existing,
(Existing) (Existing) (Existing) (Existing) (Existing) (History)
reset)
27 Fault 1 in pressure control valve system for 1st clutch b034 02 ON ON E. ↔ 34 EC ↔ 34 34
28 Fault 1 in pressure control valve system for 2nd clutch b035 02 ON ON E. ↔ 35 EC ↔ 35 35
29 Fault 1 in pressure control valve system for 3rd clutch b036 02 ON ON E. ↔ 36 EC ↔ 36 36
30 Fault 1 in pressure control valve system for 4th clutch b037 02 ON ON E. ↔ 37 EC ↔ 37 37
31 Fault 2 in pressure control valve system for R clutch b038 02 ON ON E. ↔ 38 EC ↔ 38 38
32 Fault 2 in pressure control valve system for H clutch b042 02 ON ON E. ↔ 42 EC ↔ 42 42
33 Fault 2 in pressure control valve system for L clutch b043 02 ON ON E. ↔ 43 EC ↔ 43 43
34 Fault 2 in pressure control valve system for 1st clutch b044 02 ON ON E. ↔ 44 EC ↔ 44 44
35 Fault 2 in pressure control valve system for 2nd clutch b045 02 ON ON E. ↔ 45 EC ↔ 45 45
36 Fault 2 in pressure control valve system for 3rd clutch b046 02 ON ON E. ↔ 46 EC ↔ 46 46
37 Fault 2 in pressure control valve system for 4th clutch b047 02 ON ON E. ↔ 47 EC ↔ 47 47
38 Fault 2 in pressure control valve system for R clutch b048 02 ON ON E. ↔ 48 EC ↔ 48 48
39 Fault in oil flow detection valve system for H clutch b052 02 ON ON E. ↔ 52 EC ↔ 52 52
40 Fault in oil flow detection valve system for L clutch b053 02 ON ON E. ↔ 53 EC ↔ 53 53
41 Fault in oil flow detection valve system for 1st clutch b054 02 ON ON E. ↔ 54 EC ↔ 54 54
42 Fault in oil flow detection valve system for 2nd clutch b055 02 ON ON E. ↔ 55 EC ↔ 55 55
43 Fault in oil flow detection valve system for 3rd clutch b056 02 ON ON E. ↔ 56 EC ↔ 56 56
44 Fault in oil flow detection valve system for 4th clutch b057 02 ON ON E. ↔ 57 EC ↔ 57 57
45 Fault in oil flow detection valve system for R clutch b058 02 ON ON E. ↔ 58 EC ↔ 58 58
46 Fault in engine speed sensor system b060 02 ON ON E. ↔ 60 EC ↔ 60 60
47 Fault in transmission input shaft speed sensor system b061 02 ON ON E. ↔ 61 EC ↔ 61 61
Fault in transmission intermediate shaft speed sensor
48 b062 02 ON ON E. ↔ 62 EC ↔ 62 62
system
Fault in transmission output shaft speed sensor
49 b063 02 ON ON E. ↔ 63 EC ↔ 63 63
system
50 Short circuit in lock-up clutch solenoid system b071 02 ON ON E. ↔ 71 EC ↔ 71 71
51 Short circuit in H clutch solenoid b072 02 ON ON E. ↔ 72 EC ↔ 72 72
52 Short circuit in L clutch solenoid b073 02 ON ON E. ↔ 73 EC ↔ 73 73
53 Short circuit in 1st clutch solenoid b074 02 ON ON E. ↔ 74 EC ↔ 74 74
54 Short circuit in 2nd clutch solenoid b075 02 ON ON E. ↔ 75 EC. ↔ 75 75
55 Short circuit in 3rd clutch solenoid b076 02 ON ON E. ↔ 76 EC. ↔ 76 76
56 Short circuit in 4th clutch solenoid b077 02 ON ON E. ↔ 77 EC. ↔ 77 77
57 Short circuit in R clutch solenoid b078 02 ON ON E. ↔ 78 EC. ↔ 78 78
58 Disconnection in lock-up clutch solenoid system b091 02 ON ON E. ↔ 91 EC ↔ 91 91
59 Disconnection in H clutch solenoid b092 02 ON ON E. ↔ 92 EC ↔ 92 92
60 Disconnection in L clutch solenoid b093 02 ON ON E. ↔ 93 EC ↔ 93 93
61 Disconnection in 1st clutch solenoid b094 02 ON ON E. ↔ 94 EC ↔ 94 94

Table Of Service Codes And Action Codes Related To Transmission Controller (Continued)
Monitor panel display Controller LED display
gear Central temperature
Service Action
No. Details of failure shifting warning 15° Below
code code
caution lamp (60 ° F) 15°
(Existing,
(Existing) (Existing) (Existing) (Existing) (Existing) (History)
reset)
62 Disconnection in 2nd clutch solenoid b095 02 ON ON E. ↔ 95 EC ↔ 95 95
63 Disconnection in 3rd clutch solenoid b096 02 ON ON E. ↔ 96 EC ↔ 96 96
64 Disconnection in 4th clutch solenoid b097 02 ON ON E. ↔ 97 EC ↔ 97 97
65 Disconnection in R clutch solenoid b098 02 ON ON E. ↔ 98 EC ↔ 98 98
66 Fault in model selection system rotary switch b0A1 04 ON ON E. ↔ A1 EC ↔ A1 A1
Fault in torque converter oil temperature sensor
67 b0A2 02 ON ON E. ↔ A2 EC ↔ A2 A2
system
69 Fault in air pressure sensor system b0b3 02 ON ON E. ↔ b3 EC ↔ b3 b3
Fault in retarder brake oil level sensor (right)
70 b0b4 02 ON ON E. ↔ b4 EC ↔ b4 b4
system
72 Fault in connector connection b0c1 04 ON ON E. ↔ C1 EC ↔ C1 C1
73 Short circuit with ground in BCV solenoid system b0c4 c4 ON ON E. ↔ C4 EC ↔ C4 C4
74 Disconnection in BCV solenoid system b0c6 c4 ON ON E. ↔ C6 EC ↔ C6 C6
75 Short circuit in BCV solenoid system b0c8 c4 ON ON E. ↔ C8 EC ↔ C8 C8
76 Transmission filter clogging warning b0d1 01 OFF ON E. ↔ d1 EC ↔ d1 d1
Torque converter oil temperature overheat
77 b0d2 05 OFF ON E. ↔ d2 EC ↔ d2 d2
warning
78 Engine water temperature overheat warning b0d3 05 OFF ON E. ↔ d3 EC ↔ d3 d3
79 Tilt warning b0d5 07 OFF OFF E. ↔ d5 EC ↔ d5 d5
80 Radiator water level drop warning b0d6 01 OFF OFF E. ↔ d6 EC ↔ d6 d6
81 Fault in charging circuit system b0d7 01 OFF ON E. ↔ d7 EC ↔ d7 d7
82 Engine overrun actuated b0d8 03 OFF OFF E. ↔ d8 EC ↔ d8 d8
83 Engine overshoot b0d9 02 ON ON E. ↔ d9 EC ↔ d9 d9
84 Drop in battery direct power source voltage b0dA 04 ON ON E. ↔ dA EC ↔ dA dA
85 Drop in main power source voltage b0db 04 ON ON E. ↔ db EC ↔ db db
86 Steering oil temperature overheat warning b0E5 05 OFF OFF E. ↔ E5 EC ↔ E5 E5
87 Drop in air pressure b0E9 05 OFF OFF E. ↔ E9 EC ↔ E9 E9
Transmission lubricating oil temperature
88 b0F4 02 OFF OFF E. ↔ F4 EC ↔ F4 F4
overheat warning
89 Drop in engine oil pressure b0F5 04 OFF OFF E. ↔ F5 EC ↔ F5 F5
90 Fault in brake circuit system b0F6 c4 OFF OFF E. ↔ F6 EC ↔ F6 F6
* Applicable only for mechanical governor specification truck

Note 1: "Existing" means that the problem is still occurring; "History" means that the problem occurred in the past.
Note 2: If the problem is still existing, the alarm buzzer will also sound. (When the central warning lamp is ON).
Note 3: Reset fault are kept as existing fault for 5 minutes by the transmission controller only; after that, they
are saved as a service code for past fault.
Note 4: For details of the method of display of the service code for reset fault on the monitor panel, see
MONITOR PANEL ACTION CODE AND SERVICE MODE FUNCTION, SERVICE CODE
AND TROUBLE DATA DISPLAY MODE in the Foreword to the Troubleshooting Section. For the method
of displaying the transmission controller LED SERVICE CODE TO MEMORY in the Foreword to
the Troubleshooting Section.

3. TABLE OF SERVICE CODES AND ACTION CODES RELATED TO SUSPENSION CONTROLLER
Table Of Service Codes And Action Codes Related To Suspension Controller

Other Controller
Central LED display
No. Details of failure Service code Action code gearshifting
warning lamp
caution lamp
(Existing,
(Existing) (Existing) (Existing) (Existing)
reset)
1 Fault in power source system d001 - OFF OFF E. ↔ 01
2 Fault in controller d002 - OFF OFF E. ↔ 02
3 Fault in pressure sensor (right) system d011 02 ON ON E. ↔ 11
4 Fault in pressure sensor (left) system d012 02 ON ON E. ↔ 12
5 Fault in travel speed sensor system d015 02 ON ON E. ↔ 12
6 Fault in steering sensor system d016 02 ON ON E. ↔ 16
7 Fault in solenoid 1 system d021 02 ON ON E. ↔ 21
10 Fault in network system d0C1 - OFF OFF E. ↔ C1
11 Defective model selection data d0C2 - OFF OFF E. ↔ C2
12 Defective travel speed compensation d0C3 - OFF OFF E. ↔ C3
Note 1: "Existing" means that the problem is still occurring;

Note 2: For the items where the central warning lamp lights up, the alarm buzzer also sounds.
Note 3: For details of the method of display of the service code for reset failures on the monitor panel, see
MONITOR PANEL ACTION CODE AND SERVICE MODE FUNCTION, SERVICE CODE AND TROUBLE
DATA DISPLAY MODE in the Foreword to the Troubleshooting Section.
Note 4: Reset faults are not displayed on the suspension controller LED display.

4. Table of service codes and action codes related to PMC (Power Train Management Controller)

Controller
Other Central LED
No. Details of failure Service code Action caution warning display
lamp lamp
(Existing) (Existing) (Existing) (Existing) (Existing)
1 NV RAM data fault E001 02 ON ON 01 (flashes)
2 Drop in voltage of batter y direct power source E002 02 ON ON 02 (flashes)
3 Faulty connection of connector E003 04 ON ON 03 (flashes)
4 Fault in GSP communications E011 02 ON ON 11 (flashes)
5 Fault in GSP communications E012 02 ON ON 12 (flashes)
6 Disconnection MOM communications E013 02 ON ON 13 (flashes)
7 Fault in MOM communications E014 02 ON ON 14 (flashes)
8 Disconnection in TMS communications E015 15 ON ON 15 (flashes)
9 Fault in TMS communications E016 16 ON ON 16 (flashes)
10 Disconnection in CENSE communications E017 02 ON ON 17 (flashes)
11 Fault in CENSE communications E018 02 ON ON 18 (flashes)
12 PLM communication faulty 1 E026 02 ON ON 26 (flashes)
16 PLM communication faulty 5 E02A 02 ON ON 2A (flashes)
17 Idling validation fault E035 02 ON ON 35 (flashes)
18 Disconnection, short circuit with ground in suspicion pressure sensor (right) system E041 02 ON ON 41 (flashes)
19 Disconnection, short circuit with ground in suspension pressure sensor (left) system E042 02 ON ON 42 (flashes)
20 Short circuit in suspension pressure sensor (right) system E043 02 ON ON 43 (flashes)
21 Short circuit in suspension pressure sensor (left) system E044 02 ON ON 44 (flashes)
22 Disconnection in accelerator E054 02 ON ON 54(flashes)
23 Short circuit in accelerator signal system E055 02 ON ON 55 (flashes)
24 Fault in engine speed sensor system E056 02 ON ON 56 (flashes)
25 Fault in transmission input shaft speed sensor system E057 01 ON ON 57(flashes)
26 Fault in travel speed sensor (transmission output shaft speed sensor) system E058 01 ON ON 58 (flashes)
27 Drop in brake oil level E0A1 01 OFF OFF A1 (flashes)
28 Drop in retarder oil level E0A2 01 OFF OFF A2 (flashes)
29 Drop in hydraulic oil level E0A3 01 OFF OFF A3 (flashes)
30 Retarder filter clogged E0A5 01 OFF OFF A5 (flashes)
31 Full-flow filter clogged E0A7 01 OFF OFF A7 (flashes)
32 Hydraulic filter clogged E0A8 01 OFF OFF A8 (flashes)
33 Wear of retarder brake disc right E0b2 01 OFF OFF b2 (flashes)
34 Wear of retarder brake disc left E0b3 01 OFF OFF b3 (flashes)
35 Drop in battery electrolyte level E0b4 01 OFF OFF b4 (flashes)
36 Drop in engine oil level E0b5 01 OFF OFF b5 (flashes)
37 Air cleaner clogged E0b6 01 OFF OFF b6 (flashes)
38 Fault in network system E0C1 02 OFF OFF C1 (flashes)
39 Fault in model selection data E0C2 04 OFF OFF C2 (flashes)
40 Fault in travel speed compensation data E0C3 04 OFF OFF C3 (flashes)
Note 1: "Existing" means that the problem is still occurring.

Note 2: History faults are not saved as memory data.
Note 3: For the items where the central warning lamp lights up, the alarm buzzer also sounds.

METHOD OF USING TABLE
This table is a tool to determine if the problem with the truck is caused by a fault in the electrical system or by a
problem in the hydraulic or mechanical system.
The systems are then used to decide which troubleshooting chart (A-OO, H-OO, etc.) matches the systems
* For problems with the monitor panel system, go directly to troubleshooting of the monitor panel system chart (P-OO).
(See the contents for troubleshooting of the monitor panel).
[Method of using judgment table]
A • mark is put at the places where the fault mode and self-diagnostic display match, so check if
an error display is given on the monitor panel, and
* If an error display is given, go to the troubleshooting chart reference at the bottom ( )
of the judgment table.................................................................................................................................(A-OO).
* If a problem has appeared but no error display is given, go to the troubleshooting chart reference
on the right side ( ) ...................................................................................................................................(H-OO).
If no input signal is displayed, go to the troubleshooting code at the bottom of the judgement table...... (P-OO).
* If there is no• mark, go directly to the troubleshooting code on the right side ( ).
<Example> Failure mode "Excessive shock when starting".
Procedure Check if an error code is given on the dispaly of the monitor panel or on the controller dispaly.
FIGURE 4-49. JUDGEMENT TABLE
NOTE: See actual chart on Page D5-26.

Judgments
* If error code [ 1• 7] is given on the dispaly..........go to troubleshooting A-12 for the transmission controller system.
* If no error code is given on the display, and there is excessive shock when moving the machine.........Go to
troubleshooting H-4 of the hydraulic system.

METHOD OF USING TROUBLESHOOTING CHARTS
1. Category of troubleshooting chart number
Troubleshooting chart Component

A-OO Troubleshooting of transmission controller system
SP-OO Troubleshooting of suspension controller input signal system
LC-OO Troubleshooting of payload meter (card type) system
H-OO Troubleshooting of hydraulic, mechanical system
P-OO Troubleshooting of machine monitor panel system
2. Method of using troubleshooting chart for each troubleshooting fault.

Troubleshooting chart number and problem. (See the examples on the next page.)
(1) The title at the top of the troubleshooting chart gives the fault problem with the truck.
(2) Distinguishing conditions
Even with the same fault (problem), the method of troubleshooting may differ according to the model, component,
or problem. In such cases, the fault (problem is further divided into sections marked with small letters (for
example, a) ), so go to appropriate section to carry out troubleshooting.
If the troubleshooting chart is not divided into sections, start troubleshooting from the first check item in the fault.
(3) General precautions
When carrying out troubleshooting for the fault (problem), precautions that apply to all items are given at the top
of the page and marked with*.
The precautions marked * must always be followed first before carrying out the check inside the (box).
(4) Method of following diagnostic flow chart
• Check or measure the item inside (box), and according to the answer follow either the YES line or the NO line
to go to the next (box). (Note: The number written at the top right corner of the (box) is an index number;
it does not indicate the order to follow).
• Following the YES or NO lines according to the results of the check or measurement will lead finally to the
Cause column. Check the cause and take the action given in the Remedy column on the right.
• Below the (box) there is the method for performing an inspection or measurement. Approximate values are
given for the measurements. If the findings below the (box) are correct or the answer to the question inside
the (box) is YES, follow the YES line; if the findings are not correct, or the answer to the question is NO, follow
the NO line.
(5) Troubleshooting tools
When carrying out the troubleshooting, prepare the necessary troubleshooting tools. For details, see TOOLS
FOR TESTING, ADJUSTING, AND TROUBLESHOOTING.
A diagram or chart is given for the connector type, installation position, and connector pin number. When carrying
out troubleshooting, see this chart for details of the location for inspection and measurement of the wiring
connector and the pin number appearing in the troubleshooting flow chart for each fault.

(1) A-1 Abnormality in power source system
(2) a) [OFF] Controller self-diagnostic display LED does not light up

• When fuse BT1 (No. 10) is normal. If it is blown, check for a short circuit with the ground between the fuse and
controller.
• When the battery is normal.
• Before carrying out troubleshooting, check that all the related connectors are properly inserted.
• Always connect any disconnected connectors before going on to the next step.
FIGURE 4-50.
A-1 a) Related electrical circuit diagram
FIGURE 4-51.

ADJUSTING ELECTRONIC MONITOR
(Speedometer Module)
The speedometer on the electronic monitor are com-
mon for all models, but the input signal corresponding
to the travel speed may differ according to tire size. So
it is necessary to adjust to match the tire size.
Adjustment procedure
NOTE: Turn off the power, then remove the electronic
monitor and carry out adjustments at the rear of the
speedometer.
1. Remove the rubber cap from # 2 port at the rear FIGURE 4-52. ADJUSTING SPEEDOMETER
of the speedometer.
2. When the rubber cap is removed, a rotary switch
can be seen (See Figure 4-53).
3. Using a flat-headed screwdriver, turn this switch
and adjust to the values in the table below.
Tire size Switch 2

27.00 R49 7 or 8
4. After adjusting, fit the rubber cap securely and

install the electronic monitor.
NOTE: It may be necessary to adjust switch (2) to
obtain a correct speedometer reading. Use the table
below to compensate for incorrect speedometer read-
ing.
Switch position 0 1 2 3 4 5 6 7
Compensation (%) +7 +6 +5 +4 +3 +2 +1 0
Switch position 8 9 A B C D E F
Compensation (%) 0 -1 -2 -3 -4 -5 -6 -7
FIGURE 4-53. SWITCH LOCATION

SETTING ROTARY SWITCH
(Model Data, Network Data)
WHEN REPLACING TRANSMISSION
CONTROLLER
NOTE: If the transmission controller is replaced with a
new controller or the controller is used on another
truck, set the model data and network connection data
to match the model and specification of the truck
1. Remove left and right grommets (1) on the top

face of the old controller (controller being re -
placed) and check the settings of built-in rotary FIGURE 4-54. SETTING ROTARY SWITCH
switch (2). 1. Grommets 2. Rotary Switch
2. Remove left and right grommets (1) on the top
face of the new (replacement) controller and use
a screwdriver to turn built-in rotary switch (2) to
set the controller settings to the settings of the old
controller (settings before replacement).
3. Put left and right rubber grommets (1) back in their
original positions on the top face.
Reference
The model data are set with the right rotary switch
(switch 1) and the network connection data are
set with the left rotary switch (switch 2).
The relationship of the settings and the model
data and network connection data is as shown in
the table below.
Rotary switch combination table

Rotary switch (switch 1, 2) combinations
C0 C1 C2 C3 E0 E1 E2 E3
(Switch 1 setting) - (Switch 2 setting)
ABS system NO NO NO NO YES YES YES YES
PMC controller YES NO YES NO YES NO YES NO
Suspension controller (SOS) YES YES NO NO YES YES NO NO

METHOD OF DELETING DATA FROM
MEMORY
(CONTROL FROM MONITOR PANEL)
NOTE: For details, see MONITOR PANEL ACTION
CODE AND SERVICE MODE FUNCTION in the Fore-
word of the Troubleshooting Section.
A. Outline
NOTE: If the transmission controller is going to be used
on another truck, delete the trouble data and other data
related to the current truck from the memory of the
transmission controller and PMC as follows. FIGURE 4-55. MODE SWITCHES
1. Bulb Check Switch 3. Mode Switch (Black)
1. This function is used to delete data from the 2. Mode Switch (Red)
memory of the transmission controller and PMC.
2. This function is effected by operating bulb check
switch (1, Figure 4-55) and mode change
switches (2) (the red switch at the front of the truck
and (3) (the black switch at the rear of the ma -
chine) and using the S-NET to send the command
from the monitor panel to each controller to delete
the data from memory.
3. The monitor panel accepts the operation for their
function only when the key switch is ON and the
engine is stopped.
In addition, each controller also accepts the op-
eration for this function only when the key switch
in ON and the engine is stopped.
4. To prevent the data from being deleted from the
memory of the wrong controller, an instrument
panel caution display (5, Figure 4-56) lights up to
make it possible to confirm the controller from FIGURE 4-56. CONFIRMING DATA DELETION
which the data is being deleted. 5. Caution Light

B. Deletion Method Flow Chart
Change in condition of monitor panel.
Items (1-5, Figure 4-57) shows the change in different
conditions.
FIGURE 4-57. DIFFERENT MONITOR CONDITIONS
C. Method of operation
1. (Shown at location A in figure 4-57)
Operate bulb check switch (1, Figure 4-58) and
both mode change switches (2) & (3). Keep the
switches pressed to the ON position at the same
time for at least 2.5 seconds, then release them.
(When the switches are released, they will return
automatically to the OFF position).
2. (Shown at location B in Figure 4-57)
No particular operation is needed; after Step 1
and display (3) is shown, the display automat-
ically changes to display (4).
3. (Shown at location D in Figure 4-57)
Operate bulb check switch (1, Figure 4-58) and
FIGURE 4-58. MODE SWITCHES
both mode change switches (2) & (3). Keep the
switches pressed to the ON position at the same 1. Bulb Check Switch 3. Mode Switch (Black)
time for at least 5 seconds, then release them. 2. Mode Switch (Red)
(When the switches are released, they will return
automatically to the OFF position).

D. Monitor panel functions for each condition
NOTE: For items 1 - 5 below, refer to corresponding
items 1 - 5 in Figure 4-57.
1. Normal mode: None in particular
2. Memory data deletion mode: The total for this
function
(For details, see item " C. Method of Operation").
NOTE: When entering the deletion mode, if the con-
troller detects an error, it will display a service code,
but this is not a fault for this function.
3. Deletion mode entry display:

Two items will light up at the same time for 3 FIGURE 4-59.
seconds:
• Automatic gear shifting mechatronics caution
display (5).
• Other mechatronics caution display (6).
4. Transmission controller deletion setting display:
Automatic gearshifting mechatronics caution dis-
play (5) lights up.
5. Transmission controller data deletion command
issued.
E. Remarks
The memory data deletion mode is also in the normal
mode except for the other mechatronics caution dis-
play (6).

NOTES:

TROUBLESHOOTING OF TRANSMISSION CONTROLLER SYSTEM
(A-DIAGNOSIC FLOW CHART)
Points to remember when carrying out troubleshooting of transmission controller system D5-4
Action taken by self-diagnostic device and problems on the truck D5-6
Table for transmission controller, transmission related parts D5-26
Fault in power source circuit
A-1
A-1 ( u.u ) a) (OFF) Controller self-diagnostic display LED does not light up D5-28
b001 (E. ↔ 0.1) b) Drop in voltage of controller power source is displayed D5-29
b0dA (E. ↔ d.A) c) Drop in voltage of battery direct power source is displayed D5-30
b0db (E. ↔ d.b) d) Drop in voltage of main power source is displayed D5-31
b002 (E. ↔ 0.2) e) Fault in transmission cut relay power source is displayed D5-32
A-2 b003 (E. ↔ 0.3) Fault in neutral safety circuit is displayed D5-33
Fault in controller
A-3 b005 (E. ↔ 0.5) Double engagement for clutch is displayed D5-34
A-4 b006 (E. ↔ 0.6) Fault in transmission (cut relay) is displayed D5-35
A-5 b008 (E. ↔ 0.8) Fault in rear brake solenoid is displayed D5-36
A-6 b009 (E. ↔ 0.9) Fault in exhaust brake solenoid is displayed D5-37
A-7 b0C4 (E. ↔ C.4) a) Short circuit with ground in BCV rear solenoid is displayed D5-38
b0C6 (E. ↔ C.6) b) Short circuit in BCV rear solenoid is displayed D5-38
b0C8 (E. ↔ C.8) c) Disconnection in BCV rear solenoid is displayed D5-40
Fault in speed sensor
A-8 b010 (E. ↔ 1.0) or b060 (E. ↔ 6.0)
a) Disconnection in engine speed sensor is displayed on truck or fault of
engine speed sensor is displayed (electronic governor specification on truck) D5-41
b011 (E. ↔ 1.1) or b061 (E. ↔ 6.1)
b) Disconnection in input shaft speed sensor is displayed or fault of input
shaft speed sensor is displayed D5-42
b012 (E. ↔ 1.2) or (E. ↔ 6.2)
c) Disconnection in intermediate shaft speed sensor is displayed or fault
of intermediate shaft speed sensor is displayed D5-43
b013 (E. ↔ 1.3) or (E. ↔ 6.3)
d) Disconnection in transmission output shaft speed sensor is displayed or
fault of output shaft speed sensor is displayed D5-44
D05007 TROUBLESHOOTING OF TRANSMISSION CONTROLLER SYSTEM D5-1

Speed sensor, clutch slipping
A-9 b022 (E. ↔ 2.2) or b023 (E. ↔ 2.3)
a) Input shaft speed sensor or H, L clutch is displayed D5-45
b024 (E. ↔ 2.4) or b028 (E. ↔ 2.8)
b) Transmission output shaft or speed clutch (1,2,3,4,R) is displayed D5-46
Fault in model selection
A-10 b014 (E. ↔ 1.4) a) Fault in model selection (wiring harness) is displayed D5-47
b0A1 (E. ↔ A.1) b) Fault in model selection (rotary switch) is displayed D5-48
Fault in shift lever
A-11 b007 (E. ↔ 0.7) a) Short circuit in shift lever assembly power source is displayed D5-49
b015 (E. ↔ 1.5) b) Shift lever position signal input for 2 or more circuit is displayed D5-50
b016 (E. ↔ 1.6) c) Shift lever position signal is not inputted D5-52
A-12 b017 (E. ↔ 1.7) Fault in accelerator signal is displayed D5-54
A-13 b019 (E. ↔ 1.9) Fault in transmission oil temperature sensor is displayed D5-55
Fault in pressure control valve
A-14 b032 (E. ↔ 3.2) - b038 (E. ↔ 3.8)
a) Fill switch (clutch ON) is displayed regardless of command D5-56
b042 (E. ↔ 4.2) - b048 (E. ↔ 4.8)
b) Fill signal is not inputted and clutch slipping is displayed D5-58
b-1) Checking fill signal D5-
b042 (E. ↔ 4.2) - b043 (E. ↔ 4.3)
b-2)Checking transmission input shaft speed signal H,L clutch
(check clutch slip) D5-59
b044 (E. ↔ 4.4) - b048 (E. ↔ 4.8)
b-3) Checking transmission output shaft speed signal 1-4, R clutch
(inspecting clutch slip) D5-59
A-15 b052 (E. ↔ 5.2) - b058 (E. ↔ 5.8)
When fill signal is not input (flow detector valve) D5-60
A-16 b071 (E. ↔ 7.1) - b078 (E. ↔ 7.8)
short circuit in pressure control valve solenoid is displayed D5-61
b091 (E. ↔ 9.1) - b098 (E. ↔ 9.8)
Disconnection in pressure control valve solenoid is displayed D5-61
Fault in sensor
A-17 b0A2 (E. ↔ A.2) a) Fault in torque converter oil temperature sensor is displayed D5-63
b0A3 (E. ↔ A.3) b) Fault in fuel level sensor is displayed D5-64
b0b2 (E. ↔ b.2) c) Fault in cooling water temperature sensor is displayed D5-65
b0b3 (E. ↔ b.3) d) Fault in air pressure sensor is displayed D5-66
b0b4 (E. ↔ b.4) e) Fault in retarder brake oil temperature sensor is displayed D5-67
D5-2 TROUBLESHOOTING OF TRANSMISSION CONTROLLER SYSTEM D05007

Warning display
A-18 b0d1 (E. ↔ d.1) a) Transmission filter clogged warning is displayed D5-68
b0d5 (E. ↔ d.5) b) Tilt warning is displayed D5-69
b0d6 (E. ↔ d.6) c) Drop in radiator water level warning is displayed D5-70
b0d7 (E. ↔ d.7) d) Battery charge level warning is displayed D5-71
b0E5 (E. ↔ E.5) e)Steering oil temperature overheat warning is displayed D5-72
b0F5 (E. ↔ F.5) f) Drop in engine oil pressure warning is displayed D5-73
b0F6 (E. ↔ F.6) g) Rear brake oil pressure warning is displayed D5-74
A-19 b0B7 (E. ↔ B.7) Fault in engine oil pressure sensor is displayed D5-75
A-20 b0C1 (E. ↔ C.1) Fault in connector connection is displayed D5-76
A-21 b0d2 (E. ↔ d.2) a) Torque converter oil temperature overheat warning is displayed D5-77
b0d3 (E. ↔ d.3) b) Engine water temperature overheat warning is displayed D5-77
b0E9 (E. ↔ E.9) c) Air pressure drop warning is displayed D5-77
b0F3 (E. ↔ F.3) d) Retarder brake oil temperature overheat warning is displayed D5-77
b0d8 (E. ↔ d.8) e) Engine overrun actuated is displayed D5-78
b0d9 (E. ↔ d.9) f) Engine overshoot actuated is displayed D5-78
Re-enacting failures in electrical system

With problems in the electrical circuits, there are cases where poor connections in the wirin g harnesses and
connectors occur only under special conditions. (For example, when the engine is running at high speed or the truck
is traveling at high speed on rough road surfaces)
Therefore, investigate the values for the resistance and voltage at the locations indicated by the flow chart. Even if
no fault is found, it is necessary to investigate the conditions under which the fault occu rred, and to try to re-enact
the fault condition to carry out troubleshooting.

POINTS TO REMEMBER WHEN CARRYING OUT TROUBLESHOOTING OF
1. Troubleshooting of electrical circuit and 2. Saving service code
mechanical system
The transmission controller records faults that have

If the fault display shows 2. , 3. ,4. ,5. , there occurred in the past, and can display the ones saved
are some cases where there is a problem in the in memory in the monitor panel service mode, (For
electrical circuit (sensors, wiring harnesses), and other details of the operation, see Method of operating moni-
cases where the problem is in the mechanical or tor panel service mode). When the key switch is turned
hydraulic system (ECMV) or clutch). OFF-ON, the transmission controller displays the
Therefore, if troubleshooting is carried out on the elec- codes as shown in Figure 1.
trical circuit and no problem is found, go to trou -
Therefore, by seeing these service codes, it is possible
bleshooting of the mechanical and hydraulic system.
to obtain information about problems that have oc -
On the other hand, if no problem is found during
curred in the past.
troubleshooting of the mechanical and hydraulic sys-
tem, go to troubleshooting of the electrical circuit.
FIGURE 5-1. TRANSMISSION CONTROLLER LED DISPLAY

Note: When investigating faults, if the key switch is turned ON/OFF with a connector disconn ected, the controller
may determine there is an fault, and a fault code may be recorded.
Therefore, after carrying out troubleshooting, always delete the recorded data and check to see the fault has been
deleted.
(For details of the method of deleting the data, see MONITOR PANEL DISPLAY AND SERVICE CODES).
When disconnecting and connecting the connectors of any other controller or monotor system, check to be sure the
transmission controller has not taken it as a fault

TRANSMISSION CONTROLLER SELF-DIAGNOSTIC DISPLAY CODES AND
PROBLEMS ON TRUCK
Details of fault Check the wiring harnesses and equipment given below :
Display Fault Conditions Disconnection, short circuit in wiring harness (+): Positive, (-): Negative
code Possible causes:
1. Between (+) battery - (+) circuit breaker

2. Between (+) circuit breaker - J07
Defective controller poer source
Input voltage: Max. 37V
3. Between (+) J07 - BT1 fuse No. 10 - TMB (11)
4. Between (+) TMB (11) - ATC1 (9), (17)
Min. 9V
Power source voltage inside controller
5. Between (-) ATC (8) - TMC (1) - J06 - battery relay terminal E
6. Defective alternator regulator
7. Defective power circuit inside controller
Controller system
Watch dog timer actuated Defective controller
When controller input voltage has become weak

1. Alternator output faulty
Drop in controller voltage
b001
(E. ↔ 0.1)
Input voltage, when engine speed is 500
2. Battery tends to become discharged
3. Defective charging circuit
rpm or more: Max. 19V and direct input
(E.C ↔ 0.1) voltage max. 19V
1) Between alternator terminal B - emergency steering relay terminal
B - battery 4 (+)
2) Between alternator terminal E - chassis
b0dA Drop in battery direct voltage 2. Battery tends to become discharged
(E. ↔ d.A)
Difference in electric potential between main 3. Defective charging circuit
(E.C ↔ d.A) supply voltage and battery voltage: Min. 5V 1) Between alternator terminal B - emergency steering relay terminal
B - battery 4 (+)
Drop in main supply power voltage
b0db
(E. ↔ d.b)

Difference in electric potential between
2. Battery tends to become discharged
battery direct voltage and main supply
(E.C ↔ d.b) 1) Between alternator terminal B - emergency steering relay terminal
voltage: Min. 5V
B - battery 4 (+)
Drop in solenoid supply voltage Defective solenoid circuit
b002
(E. ↔ 0.2)
Solenoid input voltage when engine speed 1. Defective transmission cut relay
is 500 rpm or more and input voltage is 20V 2. Between ATC (1), (12) - TMC (2) - R25 (5), (3) (transmission cut relay)
(E.C ↔ 0.2)
or more: 18V - BT1 fuse No. 10
1. Defective handling of machine
2. Defective controller system
N safety 1) Looseness of J07, circuit breaker, battery (+)

With key switch "ON" Shift lever at position 2) Defective insertion of fuse BT1 fuse (No. 10)
b003 other than N 3) Defective contact of connectors ATC (9), (17), TMB (11)
(E. ↔ 0.3) There may also be sudden cut in power 4) Looseness of terminal J06, battery relay E
(E.C ↔ 0.3) (when there is defective contact of control 5) Defective contact of connectors ATC1 (8), (16), TMC (1)
power and power is momentarily cut and
comes on again)
The top code in th Display code column shows the monitor panel display and the bottom code (in [ ] ) shows the
transmission controller LED display. (< less than - > greater than)

TRANSMISSION CONTROLLER SELF-DIAGNOSTIC DISPLAY CODES AND
PROBLEMS ON TRUCK
(Continued)
Symtoms that appear in truck

Condition when normal: Check with tester Action of controller when fault is when there is fault
Voltage (V), current (A), resistance value Ω detected Mechatronics display given,
warning actuated
1. Between ATC1 (9), (17) - (8) (V): 20 - 30 V
2. Between TMB (11) - TMC (1) (V): 20 - 30 V
3. Between J07 - J06 (V): 20 - 30 V Transmission suddenly shifts to
Cannot carry out control
4. BT1 fuse No. 10 is not blown Neutral during propel or truck
(Transmission is placed in Neutral)
cannot move again
Transmission suddenly shift to

Cannot carry out control
Normal controller display: Shows 0.0 or 0.C Neutral during propel or truck
(Transmission is placed in Neutral)
cannot move again
1. Between ATC (9), (17) - (8) (V): 20 - 30 V
2. ATC (7) - (8) (V): 20 - 30 V
3. Between TMB (11) - TMC (1) (V): 20 - 30 V Transmission suddenly shifts to
4. Between TMC (6) - (11) (V): 20 - 30 V Shift Neutral Neutral during propel or truck
5. Between J07 - J06 (V): 20 - 30 V cannot move again
6. Between J07 (13) - J06 (V): 20 - 30 V
7. No looseness of terminals: alternator B, battery relay B, battery (+)
1. Between ATC (7) - (8) (V): 20 - 30 V
3. Between J03 (13) - J06 (V): 20 - 30 V
Only gives self-diagnostic display; There is no problem with
does not take any action automatic gearshifting function
1. Between ATC (9), (17) - (18) (V): 20 - 30 V

3. Between J07 - J06 (V): 20 - 30 V
Only gives self-diagnostic display; There is no problem with
does not take any action automatic gearshifting function
1. Between ATC (1), (12) - chassis (V): 20 - 30 V

Transmission suddenly shifts to
2. Between TMC (2) - chassis (V): 20 - 30 V Actuates transmission cut relay
Neutral during propel or truck
3. Between R25 (5) - chassis (V): 20 - 30 V and to shifts to Neutral
cannot move again
4. Between R25 (3) - chassis (V): 20 - 30 V
1. When key switch is turned
"ON" and operation to move
truck is carried out, and it
does not move. But if shift
1. Key switch "ON" and shift lever "N"
IF there is fault when switch is lever is returned to N,
2. No looseness of terminals: battery, circuit breaker, J07, J06, battery
"ON" transmission is held at machine can start again
relay E
neutral 2. There is no mechantronics
3. Connectors TMB, TMC, ATC1 securely inserted
fault display.
3. Applicable position on
monitor panel shift position
display flashes.

Details of fault Check the wiring harnesses and equipment given below :
Display Fault condition
code Possible causes
Disconnection, short circuit in wiring harness (+): Psotive, (-): Negative
1. Defective controller
2. Defective fill switch
3. Between H SW - TM3 (3) - ATC5A (12)
Double engagement of clutch Between L SW - TM3 (6) - ATC5A (10)
b005 With double engagement of clutch, Between R SW - TM3 (9) - ATC5A (13)
input of fill sensor signal was Between 1 SW - TM4 (3) - ATC5A (14)
(E. ↔ 0.5)
detected Between 2 SW - TM4 (6) - ATC5A (15)
(E.C ↔ 0.5) Double engagement: Actuated for Between 3 SW - TM4 (9) - ATC5A (11)
2.1 - 4.7 sec Between 4 SW - TM4 (12) - ATC5A (16)
Disconnection, short circuit, short

circuit with ground in transmisssion
b006 cut relay 1. Defective transmission cut relay
(E. ↔ 0.6) Transmission cut relay output 2. Between ATC1 (15) - TMC (3) - R25 (2), (1) (transmission cut relay) BT1 fuse
(E.C ↔ 0.6) terminal voltage No. 10
• When actuated: > 11V
• When not actuated: < 11V
Short circuit with ground in 12V
b007
output circuit 1. Between (+) ATC2 (14) - TMB (1) - SF (1)
(E. ↔ 0.7)
(Shift lever power supply) 2. Defective voltage circuit inside controller
(E.C ↔ 0.7)

12V output terminal voltage, < 6V
circuit with ground in rear brake 1. Between (+) ASTC1 (13) - TMB (16) - RH4 (6) - SL4 (1)
b008
prevention solenoid 2. Between (-) SL4 (2) - RH4 (5) - GND ER
(E. ↔ 0.8)
(E.C ↔ 0.8)
Rear brake 3. Between (+) ATC1 (5) - TMC (10) - BT1 fuse No. 10
• When actuated: > 11V 4. Defective rear brake solenoid
•When not actuated < 11V
circuit with ground in exhaust brake 1. Between (+) ATC1 (14) - TMB (15) - RH4 (5) - GND ER
b009
solenoid 2. Between (-) SL5 (2) - RH4 (5) - GND ER
(E. ↔ 1.0)
(E.C ↔ 1.0)
Exhaust brake 3. Between (+) SL5 (1) RH4 (5) - BT1 fuse No. 10
• When actuated: > 11V 4. Defective exhaust brake solenoid
• When not actuated: < 11V
1. Engine speed sensor
1) Between E12 (1) - J09M (9) - TMD (13) - ATC3A (13)
Defective engine speed sensor output
b010
(E. ↔ 1.0)

Engine speed less than 350 rpm
2) Between E12 (2) - J09M (10) - TMD (14) - ATC3A (14)
2. Defective engine speed sensor
and transmission speed more than
(E.C ↔ 1.0)
500 rpm continues for 10 sec.
Disconnection in transmission input

shaft speed sensor
b011 If disconnection detection is 1. Input shaft speed sensor
actuated but there is no sensor 1) Between N1 (1) - TM2 (1) - ATC3A (2)
(E. ↔ 1.1)
signal 2) Between N2 (2) - TM2 (2) - ATC3A (14)
(E.C ↔ 1.1)
2. Defective input shaft speed sensor
Defective transmission intermediate

b012 shaft speed sensor output 1. Intermediate shaft speed sensor
(E. ↔ 1.2) If disconnection detection is 1) Between N2 (1) - TM2 (3) - ATC3A (12)
(E.C ↔ 1.2) actuated but there is no sensor 2) Between N2 (2) - TM2 (4) - ATC3A (14)
signal
The top code in the Display code column shows the monitor panel display and the bottom code in
( [ ]) shows
the transmission controller LED display. (< less than - > greater than)

(Continued)
Symptoms that appear

in truck when tere is
Condition when normal: Check with tester Action of controller
fault Mechatronics
Voltage (V), current (A), resistance value Ω when fault is detected
display given, warning
actuated
Display is as shown in the table below when shift lever is at Neutral
H SW (male) - chassis TM3 (male) (3) - chassis ATC5A (female) (12) - chassis > 1M Ω or > 1 M Ω
between terminals
L SM (male) - chassis TM3 (male) (6) - chassis ATC5A (female) (10) - chassis
Transmission suddenly
Actuates transmission
R SW (male) - chassis TM3 (male) (9) - chassis ATC5A (female) (13) - chassis shifts to Neutral during
cut relay and shift to
1 SW (male) - chassis TM3 (male) (3) - chassis ATC5A (female) (14) - chassis propel or truck cannot
Neutral
move again
2 SW (male) - chassis TM3 (male) (6) - chassis ATC5A (female) (15) - chassis
AT1 TMC R25 (V) Ω shifts to Neutral during
Actuates transmission propel or truck cannot
(15) - chassis (1) - chassis (1) - chassis 20 - 30 V -
cut relay and shift to move again
- - Between relay - 100 - 500 Ω Neutral
(1) - (2)
1. Between ATC2 (14) - chassis (V): 12V 12V output circuit Transmission suddenly
2. Between TMB (1) - chassis (V): 12V OFF (does not give shifts to Neutral during
3. Between SF (1) - (2) (V): 12V +12V) propel or truck cannot
4. Each terminal of ATC2 (14), TMB (1), DF (1) - chassis: > 1MΩ Shifts to Neutral move again
Even when engine
Only gives self- speed exceeds 2,600
1. Between ATC2 (13) - chassis: 20 - 60 Ω
diagnostic display; rpm and engine
2. Between SL4 (male) (1) - (2): 20 - 60 Ω does nottake any overruns, brake to
3. Between ATC1 (13) - ATC1 (4) (V): 20 30 V action prevent overrun is not
actuated
Even when accelerator
pedal is released and
1. Between ATC1 (14) - chassis: 20 - 60 Ω
Operation of exhaust retarder lever is
2. Between SL4 (male) (1) - (2): L 20 - 60 Ω brake function stopped opeated, exhaust brake
3. Between ATC (5) - (14) (V): 20 - 30 V is not actuated.
1. gearshifting
Speed range used
1. Engine speed display on monitor panel is normal. becomes impossible.
during propel is
2. If shift lever is set to
2. Between ATC3A (13) - (14): 500 - 1,000 Ω, AC: > 0.5V maintained
Neutral, it becomes
3. Between each terminal ATC3A (13), (14) - chassis: > 1MΩ If shift lever is at
impossible to move
4. Between E12 (male) (1) - (2): 500 - 1,000Ω Neutral, transmission
truck again unless it is
is held in Neutral
stopped.
1. Gearshifting bec-
Speed range used omes impossible.
ATC3A (female) TM2 (male) N1 (male) Ω. during propel is 2. If shift lever is set
maintained to Neutral, it bec-
Between (2) - (14) Between (1) - (2) Between (1) - (2) 500 - 1,000 Ω If shift lever is at omes impossible
Each terminal - chassis > 1M Ω. Neutral, transmission to move truck
is held in Neutral again unless it is
stopped.
1. Gearshifting be
comes impossi
Speed range used
ble.
ATC3A (female) TM2 (male) N2 (male) Ω during propel is
2. If shift lever is set
maintained
Between (14) - (12) Between (3) - (4) Between (1) - (2) 500 - 1,000 Ω to Neutral, it be
If shift lever is at
comes imposs
Each terminal - chassis > 1M Ω. Neutral, transmission
‘ ible to move
is held in Neutral
truck again un
less it is stopped.

Details of abnormality Check the wiring harnesses and euipment given below:
Display Fault condition Disconnection, short circuit in wiring harness (+): Positive, (-): Negative
Disconnection in transmission
output shaft speed ssensor
If disconnection detection is
actuated but there is no 1. Output shaft speed sensor
b013
sensor signal 1) Between N3 (1) - TM2 (5) - ATC3A (3)
(E. ↔ 1.3)
2) Between N3 (2) - TM2 (6) - ATC3A (14)
(E.C ↔ 1.3) 2. Defective output shaft speed sensor
Defective model selection signal

b014 After the key switch is
turned "ON", depending on 1. Between ATC5B (13) - ATC1 (8)
(E. ↔ 1.4)
the wiring harness, the 2. Defective contact of ATC5B, ATC1 connector
(E.C ↔ 1.4) model selection signal
does not match
Short circuit, short circuit with 1. R Between ATC5B (2) - TMB (2) - SF (3)
b015 ground in lever signal circuit N Between ATC5B (3) - TMB (3) - SF (4)
(E. ↔ 1.5) When two or more lever D Between ATC5B (4) - TMB (4) - SF (5)
(E.C ↔ 1.5) signals are generated, and 5 Between ATC5B (5) - TMB (5) - SF (6)
this continues for 3 seconds 4 Between ATC5B (6) - TMB (6) - SF (7)
3 Between ATC5B (7) - TMB (7) - SF (8)
L Between ATC5B (8) - TMB (8) - SF (9)
GND Between ATC5A (16) - TMB (9) - SF (2)
b016 Disconnection in lever signal circuit 2. Defective shift lever
(E. ↔ 1.6)
When there is no lever
(E.C ↔ 1.6) signal for 3 seconds
Accelerator signal circuit

Disconnection, defective adjustment
of mount, link out of position 1. Between ATC3B (11) - TMA (13) - C/V.T (1)
b017 Voltage between ATC3B (11) 2.
3.
Defective adjustment of clearance of sensor mount
Damaged accelerator pedal link
(E. ↔ 1.7) sand chassis
4. Defective acceleration sensor
(E.C ↔ 1.7) • > 4.7± 0.1V
5. Defecrive engine controller acceleration sensor power source circuit
• < 0.6± 0.1V
Short circuit with ground in

transmission valve oil temperature
b019 1. Between (+) ATC3B (9) - TM4 (13) - C/V.T (1)
circuit
(E. ↔ 1.9)
When transmission oil
(E.C ↔ 1.9) temperature sensor signal
Between (-) ATC3A (16) - TM4 (14) - C/V.T (2)
2. Defective transmission valve lil temperature sensor
is more than 150°C
b022 Clutch slipping or defective
 transmission speed sensor.
b028 When the input shaft 1. Input shaft 1) Between N1 (1) - TM2 (1) - ATC3A (2)
speed, intermediate shaft Speed sensor 2) Between N1 (2) - TM2 (2) - ATC3A (14)
(E. ↔ 2.2)
speed, output shaft speed 2. Output shaft 1) Between N3 (1) - TM2 (1) - ATC3A (5)
(E.C ↔ 2.2)
are converted and it is Speed sensor 2) Between N3 (2) - TM2 (6) - ATC3A (14)
 found that there is an fault 3. One of following clutches worn or damaged: H, L, 1st, 2nd, 3rd, 4th, R
(E. ↔ 2.8) with either the HL clutch or
(E.C ↔ 2.8) speed clutch.
b022
Defective H clutch or input shaft See itmes for display codes b022 - b028
(E. ↔ 2.2)
speed sensor (E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
(E.C ↔ 2.2)
b023
Defective L clutch or input shaft See items for display codes b022 - b028
(E. ↔ 2.3)
speed sensor system (E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
(E.C ↔ 2.3)
The top code in the Display code column shows the monitor panel display and the bottom code (in [ ] ) shows

(Continued)
Symptoms that appear in
Condition when normal: Check with tester Action of controller truck when there is fault
Voltage (V), current (A), resistance value Ω when fault is detected Mechatronics display
given, warning actuated
1. Speedometer shows
0 km/h when moving,
Speed range used
and gearshifting
during propel is
ATC3A (female) TM2 (male) N3 (male) Ω cannot be carried out.
maintained
2. If shift lever is shifted
Between (3) - (14) Between (5) - (6) Between (1) - (2) 500 - 1,000 Ω If shift lever is at
to Neutral, it becomes
N3 (1) - TM2 (5) - ATC3A (3) - chassis Neutral, transmission
> 1 MΩ impossible to move
is held in Neutral
truck again unless it is
stopped.
If there is fault when When key switch is
1. Between ATC5B (female) (13) - ATC1 (female) (8): 0 Ω key switch is turned turned "ON", truck cannot
2. ATC5B, ATC1 connectors are securely inserted. "ON", transmission is move off even when shift
held in Neutral. lever is operated.
1. Shifts to same speed
Shift lever position ATC5B TMB SF (V)
Set in order of priority range or higher than
N>D>5>4>3>L range set by shift
R (2) - chassis Between (2) - (9) Between (3) - (2) < 1.5 V (1.0 V) If it is together with R, lever.
N (3) - chassis Between (3) - (9) Between (4) - (2) it is taken as N 2. Stays in Neutral and
cannot move.
D (4) - chassis Between (4) - (9) Between (5) - (2)
5 (5) - chassis Between (5) - (9) Between (6) - (2)

1. Shifts to speed range
higher than range set
4 (6) - chassis Between (6) - (9) Between (7) - (2) by shift lever.
3 (7) - chassis Between (7) - (9) Between (8) - (2) Holds at position 2. Stays in Neutral and
before signal stopped cannot move.
L (8) - chassis Between (8) - (9) Between (9) - (2)
3. Impossible to shift
When lever is not in the above position / Between above terminals > 15V (24V) between FORWARD
and REVERSE
1. Automatic gear-
shifting is carried
out with normal 1. Transmission shift
mode shock becomes
ATC3B TMA WAS2 Ω
2. Control of clutch oil greater
(11) - chassis Between (13) - chassis Between (2) - (3) 0.6 - 4.5V pressure is carried 2. Immediately shifts up
out as for when acc- when going downhill
elerator is fully
depressed
Clutch oil pressure

ATC3B,3A (female) TM4 (female) C/V.T (male) Ω
control is carried out in Transmission shift shock
Between (9) -(16) Between (13) - (140 Between (1) - (2) 1 KΩ. - 100 KΩ mode used before becomes greater
(9) - chassis (13) - chassis (1) - chassis fault occurred
1
1. Transmission
ATC3A (female) Ω suddenly shifts to
Neutral during propel
Between (2) - (14) 500 - 1,000 Ω. or truck cannot move
Between (12 - (14) again
Shift to Neutral
Between (3) - (14)
2. Power is lost when in
propel , and trans-
Each terminal - chassis > 1 MΩ mission repeatedly
shifts when going
2. See TESTING AND ADJUSTING OF TRANSMISSION
uphill
3. Transmission oil is not black enough to indicate problem
See items for display
1. Between ATC3A (female) (2) - (14): 500 - 1,000 Ω. codes b022 - b028
Shift to Neutral
2. See TESTING AND ADJUSTING OF TRANSMISSION, H clutch portion. (E. ↔ 2.2, E.C ↔ 2.2,
E. ↔ 2.8, E.C ↔ 2.8)
See items for display
1. Between ATC3A (female) (2) - (14): 500 - 1,000 Ω. codes b022 - b028
Shift to Neurtral
2. See TESTING AND ADJUSTING OF TRANSMISSION, L clutch portion. (E. ↔ 2.2, E.C ↔ 2.2,
E. ↔ 2.8, E.C ↔ 2.8)

Details of abnormality Check the wiring harnesses and equipment given
below : Disconnection, short circuit in wiring harness (+): Positive, (-): Negative
Display Fault Condition
code Possible Causes
b024
Defective 1st clutch or output shaft speed See items for display codes b022 - b028
(E. ↔ 2.4)
sensor (E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
(E.C ↔ 2.4)
b025
Defective 2nd clutch or ouput shaft speed See items for display codes b022 - b028
(E. ↔ 2.5)
sensor (E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
(E.C ↔ 2.5)
b026
See itmes for display codes b022 - b028
(E. ↔ 2.6) Defective 3rd clutch or output speed sensor
(E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
(E.C ↔ 2.6)
b027
Defective 4th clutch or output shaft speed See items for display codes b022 - b028
(E. ↔ 2.7)
sensor (E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
(E.C ↔ 2.7)
b028
Defective R clutch or output shaft speed See itmes for display codes b022 - b028
(E. ↔ 2.8)
sensor (E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
(E.C ↔ 2.8)
b032

b038 1. Dirt caught in pressure control spool
(E. ↔ 3.2) 2. Short circuit, short circuit with ground in fill detection switch
(E.C ↔ 3.2) Defective pressure control valve 1) Between H SW - TM3 (3) - ATC5A (12)
 ï When the controller is issuing the com 2) Between L SW - TM3 (6) - ATC5A (10)
(E. ↔ 3.8) mand to disengage the clutch, but the fill 3) Between R SW - TM3 (9) - ATC5A (16)
(E.C ↔ 3.8) signal is still being sent (clutch is en- 4) Between 1 SW - TM4 (3) - ATC5A (13)
gaged) 5) Between 2 SW - TM4 (6) - ATC5A (14)
6) Between 3 SW - TM4 (9) - ATC5A (15)
7) Between 4 SW - TM4 (12) - ATC5A (11)
b032
1. Dirt caught in H clutch pressure control spool
(E. ↔ 3.2) Defective H clutch pressure control valve
2. Between HSW - TM3 (3) - ATC5A (12)
(E.C ↔ 3.2)
b033
1. Dirt caught in L clutch pressure control spool
(E. ↔ 3.3) Defective L clutch pressure control valve
2. Between LSW - TM3 (6) - ATC5A (10)
(E.C ↔ 3.3)
b034
1. Dirt caught in 1 clutch pressure control spool
(E. ↔ 3.4) Defective 1st clutch pressure control valve
2. Between 1SW - TM4 (3) - ATC5A (13)
(E.C ↔ 3.4)
b035
(E. ↔ 3.5) Defective 2nd clutch pressure control valve
(E.C ↔ 3.5)
b036
(E. ↔ 3.6) Defective 3rd clutch pressure control valve
2. Between 3SW - Tm4 (9) - ATC5A (15)
(E.C ↔ 3.6)
b037
(E. ↔ 3.7) Defective 4th clutch pressure control valve
(E.C ↔ 3.7)
b038
1. Dirt caught in R clutch pressure control spool
(E. ↔ 3.8) Defective R clutch pressure control valve
2. Between RSW - TM3 (9) - ATC5A (16)
(E.C ↔ 3.8)

(Continued)
Action of
controller Symptoms that appear in truck when there is
Condition when normal: Check with tester
when fault Mechantronics display given, warning
Voltage (V), current (A), resistance value Ω
fault is actuated
detected
See items for display codes b022 - b028
1. Between ATC3A (female) (3) - (14): 500 - 1,000 Ω Shift to
(E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
2. SeeTESTING AND ADJUSTING OF TRANSMISSION, 1st clutch portion. Neurtral

(E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
2. See TESTING AND ADJUSTING OF TRANSMISSION, 2nd clutch portion. Neutral

(E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
2. See TESTING AND ADJUSTING OF TRANSMISSION, 3rd clutch portion. Neutral

(E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
2. See TESTING AND ADJUSTING OF TRANSMISSION, 4th clutch portion. Neutral

(E. ↔ 2.2, E.C ↔ 2.2, E. ↔ 2.8, E.C ↔ 2.8)
2. See TESTING AND ADJUSTING OF TRANSMISSION, R clutch portion. Neutral
When transmission shift is at N, conditions are as in table below Ω
H SW (male) - chassis TM3 (male) (3) - chassis ATC5A (female) (12) - chassis > 1 MΩ
or
H SW (male) - chassis TM3 (male) (6) - chassis ATC5A (female) (10) - chassis > 1M Ω
between Shift to Transmission suddenly shifts to Neutral during
H SW (male) - chassis TM3 (male) (9) - chassis ATC5A (female) (16) - chassis
terminals
Neutral propel or truck cannot move again
Shift to Transmission suddenly shifts to neutral during

H SW (male) - chassis TM3 (female) ATC5A (female) > 1 M Ω or > 1 M Ω
(3) - chassis (12) - chassis between terminals
L SW (male) TM3 (female) ATC5A (female) > 1 M Ω or > 1 M Ω Shift to Transmission suddenly shifts to neutral during
(6) - chassis (10) - chassis between terminals Neutral propel or truck cannot move again

1 SW (male) - chassis TM4 (female) ATC5A (female) > 1 M Ω or > 1 M Ω

2 SW (male) - chassis TM4 (female) ATC5A (female) > 1 M Ω or >1 M Ω.

3 SW (male) - chassis TM4 (female) ATC5A (female) > 1 M Ω or > 1 M Ω
(9) - chassis (15) - chassis between terminals
4 SW (male) - chassis TM4 (female) ATC5A (female) >1 M Ω or > 1 M Ω


R SW (male) - chassis TM3 (female) ATC5A (female) >1 M Ω or > 1 M Ω

Details of abnormality Check the wiring harnesses and
equipment given below: Disconnection, short circuit in wiring
harness (+): Positive, (-): Negative
b042

b048 Defective pressure control valve
(E. ↔ 4.2) When it is tried to engage the clutch, the controller
Pressure control spool is stuck at clutch disengage position
(E.C ↔ 4.2) issues the command, but the fill sensor signal is not
 given, and the clutch is not engaged
(E. ↔ 4.8)
(E.C ↔ 4.8)
b042
(E. ↔ 4.2) Defective H clutch pressure control valve Pressure control spool is stuck at clutch disengage position
(E.C ↔ 4.2)
b043
(E. ↔ 4.3) Defective L clutch pressure control valve Pressure control spool is stuck at clutch disengage position
(E.C ↔ 4.3)
b044
(E. ↔ 4.4) Defective 1st clutch pressure control valve Pressure control spool is stuck at clutch disengage position
(E.C ↔ 4.4)
b045
(E. ↔ 4.5) Defective 2nd clutch pressure control valve Pressure control spool is stuck at clutch disengage postion
(E.C ↔ 4.5)
b046
(E. ↔ 4.6) Defective 3rd clutch pressure control valve Pressure control spool is stuck at clutch disengage position
(E.C ↔ 4.6)
b047
(E. ↔ 4.7) Defective 4th clutch pressure control valve Pressure control spool is stuck at clutch disengage position
(E.C ↔ 4.7)
b048
(E. ↔ 4.8) Defective R clutch pressure control valve Pressure control spool is stuck at clutch disengage position
(E.C ↔ 4.8)
1. Disconnection in fill switch circuit
1) Between H SW - TM3 (3) - ATC5A (12)
b052 2) Between L SW - TM3 (6) - ATC5A (10)
 3) Between R SW - TM3 (9) - ATC5A (16)
b058 Disconnection in fill detection switch 4) Between 1 SW - TM4 (3) - ATC5A (13)
(E. ↔ 5.2) When it is tried to engage the clutch, the controller 5) Between 2 SW - TM4 (6) - ATC5A (14)
(E.C ↔ 5.2) issues the command, but the fill sensor signal is not 6) Between 2 SW - TM4 (9) - ATC5A (15)
 given. However, the clutch is engaged. 7) Between 4 SW - TM4 (12) - ATC5A (11)
(E. ↔ 5.8) 2. Defective fill switch
(E.C ↔ 5.8)
b052 1. Between HSW - TM3 (3) - ATC5A (12)

2. Defective H clutch fill switch
(E. ↔ 5.2) Defective H clutch flow control valve
(E.C ↔ 5.2)
b053 1. Between LSW - TM3 (6) - ATC5A (10)

2. Defective L clutch fill switch
(E. ↔ 5.3) Defective L clutch flow control valve
(E.C ↔ 5.3)

b054
2. Defective 1st clutch fill switch
(E. ↔ 5.4) Defective 1st clutch flow control valve
(E.C ↔ 5.4)

(Continued)
Symptoms that appear in truck when there is

Condition when normal: Check with tester Action of controller
Mechatronics display given, warning actuated
Voltage (V), current (A), resistance value Ω when fault is detected
Transmission suddenly shift to Neutral during

propel or truck cannot move again
Normal controller display: Shows 0.0 or 0.C Shift to Neutral
Transmission suddenly shift to Neutral during

Normal controller display: Shows 0.0 or 0.C Shift to Neutral propel or truck cannot move again
Transmission suddenly shifts to Neutral during




Transmission suddently shifts to Neutral during


When each gear range is engaged using the shift checker, the fill
switch signal is given with the combinations shown in Table 1
Table 1 Relationship between gear range and fill switch signal

H L 1 2 3 4 R
Gear range used
R O O
during propel is 1. Gearshifting during propel becomes
F1 O O maintained impossible.
F2 O O If shift lever is in 2. If shift lever is shifted Neutral, it becomes
Neutral, transmission impossible to move machine.
F3 O O
is held in Neutral
F4 O O
F5 O O
F6 O O
F7 O O
When each gear range is engaged with the shift checker, the fill See items for display 1. Gearshifting during propel becomes
switch signal is issued for the combinations in Table 1 of the items codes b052 - b058 impossible.
for display codes b052 - b058 (E. ↔ 5.2, E.C ↔ 5.2, 2. If shift lever is in Neutral, it becomes
(E. ↔ 5.2, E.C ↔ 5.2, E. ↔ 5.8, E.C ↔ 5.8) E. ↔ 5.8, E.C ↔ 5.8) impossible to move truck
When each gear range is engaged with the shift checker, the fill
See items for display 1. Gearshifting during propel becomes
switch signal is issued for the combinations in Talbe 1 of the items
codes b052 - b058 impossible.
for display codes b052 - b058
(E. ↔ 5.2, E.C ↔ 5.2, 2. If shift lever is in Neutral, it becomes
(E. ↔ 5.2, E.C ↔ 5.2, E. ↔ 5.8, E.C ↔ 5.8)
E. ↔ 5.8, E.C ↔ 5.8) impossible to move truck

Display Fault condition Details of abnormality Check the wiring harnesses and equipment given bellow:
code Possible causes Disconnection, short circuit in wiring harness (+): Positive, (-): Negative
b055
(E. ↔ 5.5) Defective 2nd clutch flow control valve
2. Defective 2nd clutch fill switch
(E.C ↔ 5.5)
b056
(E. ↔ 5.6) Defective 3rd clutch flow control valve
2. Defective 3rd clutch fill switch
(E.C ↔ 5.6)
b057
1. Between 4SW - TM4 (12) - ASTC5A (11)
(E. ↔ 4.4) Defective 4th clutch flow control valve
2. Defective 4th clutch fill switch
(E.C ↔ 4.4)
b058
1. Between RSW - TM3 (9) - ATC5A (16)
(E. ↔ 5.8) Defective R clutch flow control valve
2. Defective R clutch fill switch
(E.C ↔ 5.8)
1. 1) Lock-up Between (+) L/U.t (1) - ATC1 (1)

Between (-) L/U.T (2) - ATC1 (8), (16)
2) H clutch Between (+) H.PS (2) - ATC2 (9)
Between (-) H.PS (2) - ATC2 (19)
b071 Short cirucuit in pressure control 3) L clutch Between (+) L.PS (1) - ATC2 (7)
solenoid Between (-) L.PS (2) - ATC2 (17)

b078 When it is tried to disengage the 4) 1st clutch Between (+) 1.PS (1) - ATC2 (2)
clutch, Between (-) 1.PS (2) - ATC2 (13)
(E. ↔ 7.1)
• The pressure control solenoid output 5) 2nd clutch Between (+) 2.PS (1) - ATC2 (4)
(E.C ↔ 7.1)
is turned OFF, but the solenoid Between (-) 2.PS (2) - ATC2 (15)
 current still flows 6) 3rd clutch Between (+) 3.PS (1) - ATC2 (3)
(E. ↔ 7.8) or Between (-) 3.PS (2) - ATC2 (13)
(E.C ↔ 7.8) • Excessive solenoid current flows 7) 4th clutch Between (+) 4.PS (1) - ATC2 (8)
Between (-) 4.PS (2) - ATC2 (18)
8) R clutch Between (+) R.PS (1) - ATC2 (5)
Between (-) R.PS (2) - ATC2 (15)
2. Defective pressure control solenoid
b071
Short circuit in lock-up pressure control See items for display codes b071 - b078
(E. ↔ 7.1)
solenoid (E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C ↔7.8)
(E.C ↔ 7.1)
b072
Short circuit in H clutch pressure control See items for display codes b071 - b078
(E. ↔ 7.2)
solenoid (E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C ↔7.8)
(E.C ↔ 7.2)
b073
Short circuit in L clutch pressure control See items for display codes b071 - b078
(E. ↔ 7.3)
solenoid (E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C ↔7.8)
(E.C ↔ 7.3)
b074
Short circuit in 1st clutch pressure See items for display codes b071 - b078
(E. ↔ 7.4)
control solenoid (E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C ↔7.8)
(E.C ↔ 7.4)
b075
Short circuit in 2nd clutch pressure See items for display codes b071 - b078
(E. ↔ 7.5)
control solenoid (E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C ↔7.8)
(E.C ↔ 5.5)

(Continued) in truck when there is
Condition when normal: Check with tester
Action of controller when fault is detected fault Mechatronics
Voltage (V), current (A), resistance value Ω
actuated
1. Gearshifting during
propel becomes
impossible.
switch signal is issued for the combinations in Table 1 of the See items for display codes b052 - b058
2. If shift lever is in
items for display codes b052 - b058 (E. ↔ 5.2, E.C ↔ 5.2, E. ↔ 5.8, E.C ↔ 5.8)
Neutral, it becomes
(E. ↔ 5.2, E.C ↔ 5.2 - E. ↔ 5.8, E.C ↔ 5.8)
impossible to move
the truck
propel becomes
impossible.
Neutral, it becomes
(E. ↔ 5.2, E.C ↔ 5.2 - E. ↔ 5.8, E.C ↔ 5.8)
impossible to move
truck.
propel becomes
impossible.,
Neutral, it becomes
(E. ↔ 5.2, E.C ↔ 5.2 - E. ↔ 5.8, E.C ↔ 5.8)
impossible to move
truck
propel becomes
impossible.
Neutral, it becomes
(E. ↔ 5.2, E.C ↔ 5.2 - E. ↔ 5.8, E.C ↔ 5.8)
impossible to move
truck
ATC1 (female) ATC2 (female) Ω

Between (1) - (8), (16) - 30 - 80 Ω
Between (9) - (19)
Between (7) - (17) Actuates transmission cut relay and shifts to
Between (2) - (13) Neutral Transmission suddenly
-
shifts to Neutral during
Between (4) - (15)
propel or truck cannot
Between (3) - (13) move again
5 - 25 Ω
Between (8) - (18)
Between (5) - (15)
Resistance value between each terminal > 1 MΩ
Between each terminal - chassis > 1 MΩ
Check with Table 2 for the items for display codes b071 - b078 Actuates transmission cut relay and shifts to shifts to Neutral during
(E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C ↔ 7.8) Neutral propel or truck cannot
move again
(E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C↔ 7.8) Neutral propel or turck cannot
move again
(E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C ↔ 7.8) Neutral propel or truck cannot
move again
(E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C ↔7.8) Neutral propel or truck cannot
move again
Check with table 2 for the items for display codes b071 - b078 Actuates transmission cut relay and shifts to shifts to Neutral during
(E. ↔ 7.1, E.C ↔ 7.1, E. ↔ 7.8, E.C ↔7.8) Neutral propel or truck cannot
move again

Display Fault condition below: Disconnection, short circuit in wiring harness (+): Positive, (-): Negative
b076
Short circuit in 3rd clutch pressure control See items for display codes b071 - b078
(E. ↔ 7.6)
solenoid (E. ↔ 7.1, E.C ↔ 7.1- E. ↔ 7.8, E.C ↔ 7.8)
(E.C ↔ 7.6)
b0077
Short circuit in 4th clutch pressure control See items for display codes b071 - b078
(E. ↔ 7.7)
solenoid (E. ↔ 7.1, E.C ↔ 7.1- E. ↔ 7.8, E.C ↔ 7.8)
(E.C ↔ 7.7)
b0078
Short circuit in R clutch pressure control See items for display codes b071 - b078
(E. ↔ 7.7)
solenoid E. ↔ 7.1, E.C ↔ 7.1- E. ↔ 7.8, E.C ↔ 7.8)
(E.C ↔ 7.7)
1. 1) Lock - up Between (+) L/U.T (1) - ATC1 (1)
Between (-) L/U.T (2) - ATC1 (8), (16)
2) H clutch Between (+) H.PS (1) - ATC2 (9)
Between (-) H.PS (2) - ATC2 (19)
3) L clutch Between (+) L.PS (1) - ATC2 (7)
Between (-) L.PS (2) - ATC2 (17)
4) 1st clutch Between (+) 1.PS (1) - ATC2 (2)
b091 Between (-) 1.PS (2) - ATC2 (13)
 5) 2nd clutch Between (+) 2.PS (1) - ATC2 (4)
b098 Disconnection in pressure control solenoid Between (-) 2.PS (2) - ATC2 (15)
(E. ↔ 9.1) When it is tried to disengage the clutch, the 6) 3rd clutch Between (+) 3.PS (1) - ATC2 (3)
(E.C ↔ 9.1) pressure control solenoid output is turned Between (-) 3.PS (2) - ATC2 (13)
 ON, but the solenoid current does not flow 7) 4th clutch Between (+) 4.PS (1) - ATC2 (8)
(E. ↔ 9.8) Between (-) 4.PS (2) - ATC2 (18)
(E.C ↔ 9.8) 8) R clutch Between (+) R.PS (1) - ASTC2 (5)
Between (-) R.PS (2) - ATC2 (15)
2. Defective pressure control solenoid
b091
Disconnection in lock-up pressure control See items for display codes b091 - b098
(E. ↔ 9.1)
solenoid (E. ↔ 9.1, E.C ↔ 9.1, E. ↔ 9.8, E.C ↔ 9.8)
(E.C ↔ 9.1)
b092
Disconnection in H clutch pressure control See items for display codes b091 - b098
(E. ↔ 9.2)
solenoid (E. ↔ 9.1, E.C ↔ 9.1, E. ↔ 9.8, E.C ↔ 9.8)
(E.C ↔ 9.2)
b093
Disconnection in L clutch pressure control See items for display codes b091 - b098
(E. ↔ 9.3)
solenoid (E. ↔ 9.1, E.C ↔ 9.1, E. ↔ 9.8, E.C ↔ 9.8)
(E.C ↔ 9.3)
b094
Disconnection in 1st clutch pressure control See items for display codes b091 - b098
(E. ↔ 9.4)
solenoid (E. ↔ 9.1, E.C ↔ 9.1, E. ↔ 9.8, E.C ↔ 9.8)
(E.C ↔ 9.4)
b095
Disconnection in 2nd clutch pressure control See items for display codes b091 - b098
(E. ↔ 9.7)
soelnoid (E. ↔ 9.1, E.C ↔ 9.1, E. ↔ 9.8, E.C ↔ 9.8)
(E.C ↔ 9.7)
b096
Disconnection in 3rd clutch pressure control See items for display codes b091 - b098
(E. ↔ 9.6)
solenoid (E. ↔ 9.1, E.C ↔ 9.1, E. ↔ 9.8, E.C ↔ 9.8)
(E.C ↔ 9.6)
b097
Disconnection in 4th clutch pressure control See items for display codes b091 - b098
(E. ↔ 9.7)
solenoid (E. ↔ 9.1, E.C ↔ 9.1, E. ↔ 9.8, E.C ↔ 9.8)
(E.C ↔ 9.7)
b098
Disconnection in R clutch pressure control See tiems for display codes b091 - b098
(E. ↔ 9.8)
solenoid (E. ↔ 9.1, E.C ↔ 9.1, E. ↔ 9.8, E.C ↔ 9.8)
(E.C ↔ 9.8)

(Continued)
Condition when normal: Check with tester Action of controller when fault is truck when there is
Voltage (V), current (A), resistance value Ω detected Mechatronics display given,
warning actuated
Transmission suddenly shifts
Check with Table 2 for the items for display codes b071 - b078 Actuates transmission cut relay
to Neutral during propel or
(E. ↔ 7.1, E.C ↔ 7.1 - E. ↔ 7.8, E.C ↔ 7.8) and shifts to Neutral
truck cannot move again
(E. ↔ 7.1, E.C ↔ 7.1 - E. ↔ 7.8, E.C ↔ 7.8) and shifts to neutral
(E. ↔ 7.1, E.C ↔ 7.1 - E. ↔ 7.8, E.C ↔ 7.8) and shifts to Neutral
When each gear range is engaged using the shift checker, the
fill switch signal is given with the combinations shown in
Table1.
Table 2 Solenoid valve check

ATC1 (female) ATC2 (female) Ω
30 - 80 1. Power is lost when pro
Between (1) - (8), (16) - Even when a disconnection is
Ω peling, and when shifting
detected, it tries to send current
up, transmission immed-
Between (9) - (19) to the solenoid
iately shifts down again
• This is because there is
Between (7) - (17) • This frequently happens
no danger of damage to
Between (2) - (13) when going uphill loaded
- the controller even if
2. Shift indicator display
Between (4) - (15) 5 - 25 Ω there is a disconnection
shows "E"
Between (3) - (13)
Between (8) - (18)
Between (5) - (15)
Resistance value between each terminal > 1 MΩ
Between each terminal - chassis > 1 MΩ
See items for display codes See items for display codes
Check with Table 2 for the items for display codes b091 - b098
b091 - b098 (E. ↔ 9.1, E.C ↔ b091 - b098 (E. ↔ 9.1, E.C
(E. ↔ 9.1, E.C ↔ 9.1 - E. ↔ 9.8, E.C ↔ 9.8)
9.1- E ↔ 9.8, E.C ↔ 9.8) ↔ 9.1- E ↔ 9.8, E.C ↔ 9.8)
b091 - b098 (E. ↔ 9.1, E.C ↔ b091 - b098 (E. ↔ 9.1, E.C
(E. ↔ 9.1, E.C ↔ 9.1 - E. ↔ 9.8, E.C ↔ 9.8)
9.1- E ↔ 9.8, E.C ↔ 9.8) ↔ 9.1- E ↔ 9.8, E.C ↔ 9.8)
b091 - b098 (E. ↔ 9.1, E.C ↔ b091 - b098 (E. ↔ 9.1, E.C
(E. ↔ 9.1, E.C ↔ 9.1 - E. ↔ 9.8, E.C ↔ 9.8)
9.1- E ↔ 9.8, E.C ↔ 9.8) ↔ 9.1- E ↔ 9.8, E.C ↔ 9.8)
Check with Tabel 2 for the items for display codes b091 - b098
b091 - b098 (E. ↔ 9.1, E.C ↔ b091 - b098 (E. ↔ 9.1, E.C
(E. ↔ 9.1, E.C ↔ 9.1 - E. ↔ 9.8, E.C ↔ 9.8)
9.1- E ↔ 9.8, E.C ↔ 9.8) ↔ 9.1- E ↔ 9.8, E.C ↔ 9.8)
b091 - b098 (E. ↔ 9.1, E.C ↔ b091 - b098 (E. ↔ 9.1, E.C
(E. ↔ 9.1, E.C ↔ 9.1 - E. ↔ 9.8, E.C ↔ 9.8)
9.1- E ↔ 9.8, E.C ↔ 9.8) ↔ 9.1- E ↔ 9.8, E.C ↔ 9.8)
b091 - b098 (E. ↔ 9.1, E.C ↔ b091 - b098 (E. ↔ 9.1, E.C
(E. ↔ 9.1, E.C ↔ 9.1 - E. ↔ 9.8, E.C ↔ 9.8)
9.1- E ↔ 9.8, E.C ↔ 9.8) ↔ 9.1- E ↔ 9.8, E.C ↔ 9.8)
b091 - b098 (E. ↔ 9.1, E.C ↔ b091 - b098 (E. ↔ 9.1, E.C
(E. ↔ 9.1, E.C ↔ 9.1 - E. ↔ 9.8, E.C ↔ 9.8)
9.1- E ↔ 9.8, E.C ↔ 9.8) ↔ 9.1- E ↔ 9.8, E.C ↔ 9.8)
b091 - b098 (E. ↔ 9.1, E.C ↔ b091 - b098 (E. ↔ 9.1, E.C
(E. ↔ 9.1, E.C ↔ 9.1 - E. ↔ 9.8, E.C ↔ 9.8)
9.1- E ↔ 9.8, E.C ↔ 9.8) ↔ 9.1- E ↔ 9.8, E.C ↔ 9.8)

Details of abnormality Check the wiring harnesses and equipment given below:
Disconnection, short circuit in wiring harness (+): Positive, (-): Negative
Defective engine speed sensor output 1. Engine speed sensor B

b060
(E. ↔ 6.0)
Engine speed less than 350 rpm and 1) Between E12 (1) - J09M (9) - TMD (13) - ATC3A (13)
transmission speed more thatn 500 2) Between E12 (2) - J09M (10) - TMD (14) - ATC3A (14)
(E.C ↔ 6.0) rpm continues for 10 sec. 2. Defective engine speed sensor
Defective output of transmission input

1. Input shaft speed sensor
shaft speed sensor
b061 When the engine speed, input shaft
1) Between N1 (1) - TM2 (1) - ATC3A (2)
2) Between N2 (2) - TM2 (2) - ATC3A (14)
(E. ↔ 6.1) speed, and intermediate shaft speed
2. Defective input shaft speed sensor
(E.C ↔ 6.1) are converted and it is found that there
is a problem in lock-up clutch and HL
clutch
Defective output of transmission
intermediated shaft speed sensor 1. Intermediate shaft speed sensor
When the input shaft speed, intermedi- 1) Between N2 (1) - TM2 (3) - ATC3A (12)
b062 ated shaft speed, and output shaft 2) Between N2 (2) - TM2 (4) - ATC3A (14)
(E. ↔ 6.2) speed are converted and it is found 2. Defective intermediate shaft speed sensor
(E.C ↔ 6.2) that there is a problem in HL clutch and
speed clutch (When disconnection de-
tection is actuated and there is no sen-
sor signal)
Defective output of transmission output
shaft speed sensor
When the engine speed, input shaft
1. Output shaft speed sensor
1) Between N3 (1) - TM2 (5) - ATC3A (3)
b063 speed, intermediate shaft speed, and
2) Between N3 (2) - TM2 (6) - ATC3A (14)
output shaft speed are converted and
(E. ↔ 6.3) 2. Defective output shaft speed sensor
it is found that there is a problem in rel-
(E.C ↔ 6.3)
ationship
b0A1 Fault in model selection

(E. ↔ A.1)
The setting of rotary switch is different
1. Defective controller
2. Defective setting of rotary switch
(E.C ↔ A.1) from the model in the software.
Short circuit with ground in torque
b0A2 converter oil temperature 1. Between (+) ATC3B (7) - TM2 (7) - TC.SE (1)
(E. ↔ A.2)
When torque converter oil temperature Between (-) ATC3A (16) - TMB (9) - TMC (5) - TM2 (8) - TC.SE (2)
(E.C ↔ A.2) sensor signal is more than 150°C 2. Defective torque converter oil temperature sensor
b0A3
Disconnection in fuel level sensor 1. Between (+) ATC5B (5) - TMA (15) - J09M (12), (15) - J02 (1) - 26 (1)
(E. ↔ A.3)
(E.C ↔ A.3)

Input voltage: > 4 V 2. Defective fuel sensor
Short circuit with ground in cooling water

temperature sensor
b0b2
(E. ↔ b.2)
When input resistance of cooling water
1. Between (+) ATC5B (5) - TMA (7) -J09M (12), (15) - J02 (1) - 26 (1)
Between (-) ATC5A (16) - TMB (9) - J09M (13), (16) - J02 (3) - 26 (2)
temperature sensor signal is more
(E.C ↔ b.2) 2. Defective coolant water temperature sensor
than 170 Ω
Disconnection in brake air pressure

b0b3 sensor 1. Between (+) ATC3B (2) - TMA (7) - RH4 (1) - SR5 (1)
(E. ↔ b.3)
When input resistance of brake air Between (-) ATC5A (16) - TMB (9) - RH4 (10) - SR5 (2)
(E.C ↔ b.3) pressure sensor signal is more than 2. Defective brake air pressure sensor
3,000 Ω
The top code in the Display code column shows the monitor panel display and the bottom code ( in [ ] ) shows
the transmission controller LED display. ( < less than - > greater than)

(Continued)
in truck when there is
Condition when normal: Check with tester Action of controller when
fault Mechatronics
Voltage (V), current (A), resistance value Ω fault is detected
actuated
1. Gearshifting be-
Gear range used during comes impossible.
1. Engine speed display on monitor panel is normal
propel maintained 2. If shift lever is in
2. Between ASTC3A (13) - (14): 500 - 1,000 AC sym: > 0.5V
If shift lever is in Neutral, Neutral, it becomes
3. Between each terminal of ATC3A (13), (14) - chassis: > 1 MΩ
transmission is held in impossible to move
4. Between E12 (male) (1) - (2): 500 - 1,000 Ω Neutral the truck agin unless
it is stopped.
1. Gearshifting be-
ATC3A (female) TM2 (male) N1 (male) Ω propel is maintained 2. If shift lever is in
Between (2) - (14) Between (1) - (2) Between (1) - (2) 500 - 1,000 Ω
Each terminal - chassis >1MΩ Neutral the truck agin unless
it is stopped.
1. Gearshifting be-
ATC3A (female) TM2 (male) N2 (male) Ω propel is maintained 2. If shift lever is in
Between (14) - (12) Between (3) - (4) Between (1) - (2) 500 - 1,000 Ω
Each terminal - chassis >1MΩ Neutral the truck agin unless
it is stopped.
1. Speedometer dis-
plays 0 km/h during
ATC3A (female) TM2 (male) N3 (male) Ω propel and gear-
Gear range used during
shifting becomes im-
Between (3) - (14) Between (5) - (6) Between (1) - (2) 500 - 1,000 Ω propel is maintained
possible.
If shift lever is in Neutral,
Between N3 (1) - TM2 (5) - ATC3A (3) - chassis > 1 MΩ 2. If shift lever is in
transmission is held in
Neutral, it becomes
Neutral
impossible to move
the truck again un-
less it is stopped.
When effort to move the
Set value of rotary switch 1 2, 3, 4, or 5 Holds at neutral truck is carried out, it
does not move.
ATC3B,3A (female) TM2 (female) TC.SE (male) Ω No display at all is given

Only gives self-diagnostic
on torque converter oil
Between (7) - (16) Between (7) - (8) Between (10 - (2) 1 KΩ − 100 ΚΩ display; does not take any
temperature gauge
action
(7) - chassis (7) - chassis (1) - chassis display on monitor panel.
ATC3B TMD J02 61 (V) Only gives self-diagnostic No display at all is given
display; does not take any on fuel level gauge
(4) - chassis (7) - chassis (15) - chassis (1) - chassis 0.2 - 0.4 V
action display on monitor panel.
When engine water temperature is between 25°C (normal temperature) and 100°C, condition is as shown in
table below.
No display at all is given
Only gives self-diagnostic
ATC3B,3A (male) TMA, TMB (male) J09M J02 61 (V) on engine water
display; does not take any
Between (15) - (9) Between (12), (15) - Between (1) - (3) Between (1) - (2) 37 Ω
temperature gauge
Between (5) - (16) action
(13), (16)  display on monitor panel.
4Ω
(5) - chassis (15) - chassis (12), (15) - chassis (1) - chassis (1) - chassis
ATC3B,3A (male) TMA, TMB (male) RH4, RH1 SR5 Ω Only gives self-diagnostic No display at all is given
Between (2) - (16) Between (7) - (9) Between (1) - (10) Between (1) - (2) 3 - 1,000 Ω
display; does not take any on air pressure gauge
action display on monitor panel.
(2) - chassis (7) - chassis (1) - chassis (10 - chassis

Display Fault condition below: Disconnection, short circuit in wiring harness (+): Positive, (-):
code Possible causes Negative
Short circuit with ground in retarder brake oil

b0b4 temperature sensor 1. Between (+) ATC3b (8) - tmd (5) - J02 (10) - 64 (1)
(E. ↔ b.4)
When retarder brake oil temperature sensor Between (-) ATC3A (16) - TMB (9) - J02 (9) - 64 (2)
(E.C ↔ b.4) signal is more than 150°C 2. Defective retarder brake oil temperature sensor
Disconnection, short circuit with ground in

b0b7 engine oil pressure sensor 1. Between ATC3B (12) - TMD (15) - J02 (2) - 27 (3)
(E. ↔ b.7)
Voltage between ATC3B (12) - chassis Between (+) ATC3A (6) - TMA (16) - J09M (11) - (14) - J01 (11) - 27 (2)
2. Defective voltage circuit inside controller
(E.C ↔ b.7) • 4.6 ± 0.1 V
3. Defective engine oil pressure sensor
• 0.4 ± 0.1 V
Improper connection of connector
b0C1
(E. ↔ C1)
After the key switch is turned "ON", de- 1. Between ATC5A (1) - ATC1 (16) .
pending on the wiring harness, the model 2. Defective contact of ATC5A connector
(E.C ↔ C1) selection signal does not match
Short circuit with ground in BCV rear solenoid
b0C4 BCV output terminal voltage
1. Defective BCV relay R04
(E. ↔ C.4) • When actuated: > 11V or above
2. Between ATC (11) - TMB (13) - R04 (1)
(E.C ↔ C.4) • When not actuated: < 11V or below
Disconnection in BCV rear solenoid

b0C6
(E. ↔ C.6)
BCV output terminal voltage 1. Defective BCV relay R04
• When actuated: > 11V or above 2. Between ATC (11) - TMB (13) - R04 (1), from R04 (2) - GND,ER
(E.C ↔ C.6)
• When not actuated: < 11V or below
Short circuit in BCV rear solenoid

b0C8
(E. ↔ C.8)
BCV output terminal voltage 1. Defective BCV relay R04
• When actuated: > 11V or above 2. Between ATC (11) - TMB (13) - R04 (2)
(E.C ↔ C.8)
• When not actuated: < 11V or below
Transmission filter clogging warning

b0d1
(E. ↔ d.1)
When the transmission oil filter switch is OFF
1. Between (+) ATC5A (6) - TMD (6) - J02 (13) - 52 (10
Between (-) J03 (8) - 52 (2)
with the torque converter outlet port oil
(E.C ↔ d.1) 2. Defective transmission filter sensor
temperature 50°C or above.
1. Between (+) ATC5A (5) - TMD (2) - SR3 (1)

b0d5 Between (-) SR3 (2) - GND.ER
Tilt warning display 2. Defective tilt sensor
(E. ↔ d.5)
(E.C ↔ d.5)
When the machine tilt angle switch is OFF.
1. Between (+) ATC5B (15) - TMD (4) - J02 (7) - 01 (9) - 03 (1)
b0d6 Drop in radiator water level warning display Between (-) 03 (2) - GND.16
(E. ↔ d.6)
When the engine cooling water level switch 2. Defective radiator water level sensor
(E.C ↔ d.6) is OFF.
the transmission controller LED display. ( < less than - > greater than)

(Continued)

Condition when normal: Check with tester Action of contoller when truck when there is fault
Voltage (V), current (A), resistance value Ω fault is detected Mechatronics display
given, warning actuated
No display at all is given

ATC3B,3A (male) TMD, TMB (male) J02 64 Ω Only gives self-
on retarder oil
diagnostic display; does
Between (8) - (16) Between (5) - (9) Between (10) - (9) Between (1) - (2) 2k W - 20k W temperature gauge
(25°C - 120°C) not take any action
(8) - chassis (5) - chassis (10) - chassis (1) - chassis display on monitor panel.
ATC3B TMD J02 27 (V) Only gives self- Drop in engine oil
(12) - chassis (15) - chassis (2) - chassis (3) - chassis 0.4 - 4.6 V diagnostic display; does pressure cannot be
not take any action detected.
Between (2) - (3)
If there is a fault when When key switch is

1. Between ATC5A (1) - ATC1 (16): 0 Ω key switch is turned turned "ON", truck
2. ATC5A, ATC1 connectors are securely inserted. "ON", transmission is cannot move even when
held at Neutral. shift lever is operated.
ATC1 TMB R04 (V) Ω

Only gives self-
(11) - chassis (13) - chassis (1) - chassis 20 - 30 V diagnostic display; does BCV is not actuated
Between relay 100 - 500 Ω not take any action
(1) and (2)
Only gives self-

ATC1 TMB R04 (V) Ω diagnostic display; does
not take any action
(11) - chassis (13) - chassis (1) - chassis 20 - 30 V BCV is not actuated
Between relay 100 - 500 Ω
(1) and (2)
Only gives self-

ATC1 TMB R04 (V) Ω diagnostic display; does
(11) - chassis (13) - chassis (1) - chassis 20 - 30 V
not take any action BCV in mistakenly
actuated
Between relay 100 - 500 Ω
(1) - (2)
1. If operations are
continued, dirt will
When transmission filter is normal, condition is as shown in table below.
circulate in transmission
Only gives self-
ATC5A TMD J02 52 circuit.
(6) - chassis (2) - chassis (13) - chassis (1) - chassis No continuity 2. Mechatronics display
not take any action
is not given.
Between (1) - (2)
3. Buzzer does not
sound.
When machine tilt angle is ± 15°, condition is as shown in table below. Only gives self- continued, truck may roll
ATC5A TMD SR3 diagnostic display; does over.
not take any action 2. Mechatronics display
(5) - chassis (2) - chassis (1) - chassis, (1) - (2) Continuity
is not given.
Only gives self- continued, there will be
When radiator water level is normal, condition is as shown in table below.
diagnostic display; does overheating.
ATC5B TMD J02 01 03 not take any action 2. Mechatronics display
(15) - chassis (4) - chassis (7) - chassis (8) - chassis (1) - chassis, (1) - (2) Continuity is not given.

Display Fault condition below: Disconnection, short circuit in wiring harness (+): Positive, (-) :
code Possible causes Negative
1. Between ATC3B (1) - TMD (1) - J01 (1) - alternaotor terminal R

b0d7 Battery charge warning display
(E. ↔ d.7) When battery charge switch is OFF with
(E.C ↔ d.7) engine speed at 500 rpm or above.
b0F5 1. Between ATC3B (12) - TMD (15) - J02 (2) - 27 (3)

Engine oil pressure drop warning
(E. ↔ F.5)
(E.C ↔ F.5)
When fault is recongnized in the engine
2. Defective engine lubricating oil circuit
3. Defective engine oil pressure sensor
speed at 700 rpm or above.
b0E5 1. Between ATC3A (11) - TMA (8) - J01 (6) - 21 (1)

Steering oil temperature overheat warning
(E. ↔ E.5)
(E.C ↔ E.5)
When steering oil tmeperature switch in
2. Defective steering oil temperature sensor
ON.
1. Between (+) ATC5A (8) - TMC (12) - J)3 (2) - BLSL (1)
b0F6 Rear brake oil pressure warning display Between BLSL (2) - BLSR (1)
(E. ↔ F.6) When bralke stroke switch is ON for 2 Between (-) BLSR (2) - GND.67
(E.C ↔ F.6) seconds. 2. Defective brake stroke sensor
b0d3 Engine water temperature overheat warning

(E. ↔ d.3) When engine water temperature sensor Abnormal rise in engine water temperature.
(E.C ↔ d.3) signal is above 102°C
b0d2 Torque converter oil temperature overheat

warning
(E. ↔ d.2)
(E.C ↔ d.2)
According to network data from monitor
Abnormal rise in torque converter oil temperature
system.
b0E9 Air pressure drop warning

(E. ↔ E.9) According to network data from monitor
Abnormal drop in air pressure inside air tank
(E.C ↔ E.9) system.
b0F3 Retarder oil temperature overheat warning

(E. ↔ F.3) According to network data from monitor
Abnormal rise in retarder oil temperature
(E.C ↔ F.3) system.
b0d8 Engine overrun actuated display Engine overrun actuated display

(E. ↔ d.8) Overrun actuated with transmission input
(E.C ↔ d.8) shaft speed more than 2,600 rpm.
Engine overshoot display

b0d9
(E. ↔ d.9)
When d.8 does not detect engine over-
Engine overshoot display (sudden spurt)
shoot display with engine speed at 2,600
(E.C ↔ d.9)
rpm or above
The top code in the Display code column shows the monitor panel display and the bottom code ( in [ ] ) shows

Symptoms that appear in truck
Condition when normal: Check with tester Action of controller when when there is fault
Voltage (V), current (A), resistance value Ω fault is detected Mechatronics display given,
warning actuated
1. Propel is possible until
control power source vol-
When engine is running (1/2 throttle or above), condition is as shown in table below. tage drops. If operations
Only gives self-
are continued, battery life
ATC3B TMD J01 (V) diagnostic display; does
will be reduced.
not take any action
(1) - chassis (1) - chassis (1) - chassis 27.5 - 29.5 V 2. Mechatronics display is not
given
3. Buzzer does not sound
1. Loses power during

ATC3A TMD J02 27
operations.
Only gives self-
Engine 1,000 (12) - chassis (15) - chassis (2) - chassis Between 1.3 - 5.0 V 2. Engine acceleration
Speed rpm (1) - (3) diagnostic display; does
becomes poor.
not take any action
1,800 (12) - chassis (15) - chassis (2) - chassis Between 2.1 - 5.0 V 3. Mechatronics display is not
rpm (1) - (3) given
When steering oil temperature is 25°C (normal temperature), condition is as shown in tabel below.
1. If operations are continued,
Only gives self-
oil may leak.
ATC3A TMA J01 21 . diagnostic display; does
2. Mechatronics display is not
not take any action
(11) - chassis (8) - chassis (6) - chassis (1) - chassis No continuity given.
When brake stroke is normal, condition is as shown in table below. 1. If operations are continued,
Only gives self-
ATC5A TMD J03 BLSL oil may leak.
(8) - chassis (12) - chassis (2) - chassis (1) - chassis Continuity not take any action
given.
- - - (1) - (2), (2) - chassis
1. Low power during operation.

Only gives self- 2. Engine acceleration be
diagnostic display; does comes poor.
not take any action 3. Mechatronics display is not
given
Only gives self-
engine may be damaged.
not take any action
given
Only gives self-
not take any action
given
Only gives self-
not take any action
given
Only gives self-
not take any action
given
Only gives self-
not take any action
given

TABLE FOR TRANSMISSION CONTROLLER,
TRANSMISSION RELATED PARTS

A-1 FAULTS IN POWER SOURCE SYSTEM
a) (OFF) Controller self-diagnostic display LED does not light up
• When fuse BT1 (No. 10) is normal.

If it is blown, check for a short circuit with the ground in the wiring harness between the fuse and controller.

b) Drop in voltage of controller power source is displayed
• When fuses BT1 (10) (19 - 20) and BT2 (8) (15 - 16) are normal.
If it is blown, check for a short circuit with the ground inside the controller and in the wiring harness between the
fuse and controller.
A-1 b) Related electrical circuit diagram

c) Drop in voltage of battery direct power source is displayed
• When fuse BT2 (8) (15 - 16) is normal.

If it is blown, check for a short circuit with the ground inside the controller and in the wiring harness between the
fuse and controller.
• Always connect any disconnected connectors before going on the next step.
A-1 c) Related electrical circuit diagram

d) Drop in voltage of main power source is displayed
• When fuse BT1 (10) (19 - 20) is normal.

If it is blown, check for a short circuit with ground inside the controller and in the wiring harness between the fuse
and controller.
A - 1 d) Related electrical circuit diagram

e) Faults in transmission cut relay power source is displayed
• When battery and charging voltage are normal

• When fuse FB1 (No. 10) is normal
A-1 e) Related electrical circuit diagram

A-2 Faults in neutral safety system is displayed
• When the key switch is turned to ON with the shift lever at a position other than N, or when the power source is
momentarily cut when moving.
A-2 Related electrical circuit diagram

A-3 Double engagement for clutch is displayed

A-4 Faults in transmission [cut relay] system displayed
• Displays disconnection, short circuit, or short circuit with chassis ground in transmission cut relay system.

A-5 Faults in rear brake solenoid circuit is displayed
A-5 related electrical circuit diagram

A-6 Faults in exhaust brake solenoid circuit is displayed

A-7
a)
Short circuit with ground in BCV rear solenoid is displayed

b) Short circuit in BCV rear solenoid is displayed
• Check that the mounting bolts of the input shaft speed sensor sre not loose.

c) Disconnection in BCV rear solenoid is displayed

A-8 Fault in speed sensor
a) -2
Disconnection in engine speed sensor [B] is displayed on truck
or
Failure of engine speed sensor is displayed on truck

b) Disconnection in input shaft speed sensor is displayed or
Failure of input shaft speed sensor is displayed
• Check that the mounting bolts of the input shaft speed sensor are not loose.
Table 1 ATC3A (female) N1 (male) Resistance

Between (2) - (14) Between (1) - (2) 500 Ω - 1000 Ω
Between (2) & chassis Between (1) & chassis > 1M Ω

c) Disconnection in intermediate shaft speed sensor is displayed or
Failure of intermediate shaft speed sensor is displayed
• Check that the mounting bolts of the intermediate shaft speed sensor are not loose.
Table 1
ATC3A (female) N2 (male) Resistance

Between (12) - (14) Between (1) - (2) 500 Ω - 1000 Ω
A-8 c) Related electrical diagram

d) Disconnection in speed sensor (transmission output shaft speed
sensor) us displayed or
Failure of output shaft speed sensor is displayed
• Check that the mounting bolts of the speed sensor are not loose.
• Before carrying out troubleshooting, check that all the related
connectors are properly inserted.
• Always connect any disconnected connectors before going on to
the next step.
Table 1 ATC3A (female) N3 (male) Resistance

A-8 d) Related electrical circuit diagram Between (3) - (14) Between (1) - (2) 500 Ω - 1000 Ω

A-9 Speed sensor, clutch slipping
a)
or
Input shaft speed sensor or H,L clutch is displayed
• Always connect any disconnected connectors before going on to the next step
Table 1
ATC3A N3 Resistance
A-9 a) Related electrical circuit diagram Between (2) - (14) Between (1) - (2) 500 Ω - 1000 Ω

Output shaft speed sensor or
b) speed clutch (1,2,3,4,R) system
is displayed
Table 1
ATC3A N3 Resistance
A-9 b) Related electrical circuit diagram Between (3) - (14) Between (1) - (2) 500 Ω - 1000 Ω

A-10 Fault in model selection (wiring harness) is displayed
Fault in model selection (wiring harness) is displayed

a)
• When the controller power source is normal.

Table 1
ATC5B ATC1 Voltage
(10) - (8) > 15 V
A-10 a) Related electrical circuit diagram (11) - (8) >1V
(12) - (8) >1V
(13) - (8) <1V

b) Fault in model selection (rotary switch) is displayed


A-11 Fault in shift lever circuit
a) Short circuit in shift lever assembly power source is displayed


b) Shift lever position signal input for 2 or more circuits is displayed

Table 1
Abnormal system System with failed wiring harness

SF (4) - ATC5B (3) - transmission neutral
N
relay R02 (2) - payload meter relay R11 (6)
SF (3) - ATC5B (2) - backup alarm relay
R
R06 (2)
D SF (5) - ATC5B (4)
5 SF (6) - ATC5B (5)
4 SF (7) - ATC5B (6)
3 SF (8) - ATC5B (7)
L SF (9) - ATC5B (8)

c) Shift lever position signal is not inputed
Table 1
Terminal of Voltage when

Lever Voltage when Shift lever
TORQFLOW position is not
position position is selected SF terminal
transmission controller selected
N ATC5B (3) < 1.0 V > 15.0 V SF (4)
R ATC5B (2) < 1.0 V > 15.0 V SF (3)
D ATC5B (4) < 1.0 V > 15.0 V SF (5)
5 ATC5B (5) < 1.0 V > 15.0 V SF (6)
4 ATC5B (6) < 1.0 V > 15.0 V SF (7)
3 ATC5B (7) < 1.0 V > 15.0 V SF (8)
L ATC5B (8) < 1.0 V > 15.0 V SF (9)


A-12 Fault in accelerator signal is displayed

A-13 Fault in transmission oil temperature sensor is displayed

A-14 Fault in pressure control valve
a) Fill switch (clutch ON) is displayed

regardless of command
Table 1
Connection of connector and fill
Fill switch
switch
Service code Corresponding Transmission When connected When open
display clutch controller
Fill switch
connector and pin Voltage Resistance Voltage Resistance
number
b042[E.↔ 4.2,
H clutch ATC5A (12) - H. SW <1V <1Ω 15 -25 V > 1 MΩ
E.C↔4.2]
b043[E.↔ 4.3,
L clutch ATC5A (10) - L. SW <1V <1Ω 15 - 25 V > 1 MΩ
E.C↔ 4.3]
b044[E.↔ 4.4,
1 clutch ATC5A (13) - 1. SW <1V <1Ω 15 - 25 V > 1 MΩ
E.C↔ 4.4]
b045[E.↔ 4.5,
E.C↔ 4.5]
b046[E↔ 4.6,
E.C↔ 4.6]
b047[E.↔ 4.7,
E.C↔ 4.7]
b048[E.↔ 4.8,
R clutch ATC5A (16) - R. SW <1V <1Ω 15 - 25 V > 1 MΩ
Ε.Χ ↔4.8]


Fill switch signal is not input
b) and clutch slipping is displayed
• Measure the clutch oil pressure of the circuit where the fault is displayed. If the oil pressure is normal, carry out
the troubleshooting below.
b-1) Inspecting fill switch signal
Table 1
Connection of connector and

Fill switch
fill switch
Service code Corresponding Transmission When connected When open
display clutch controller
Fill switch
connector and pin Voltage Resistance Voltage Resistance
number
b042[E.↔ 4.2,
H clutch ATC5A (12) - H. SW <1V <1Ω 15 -25 V > 1 MΩ
E.C↔4.2]
b043[E.↔ 4.3,
L clutch ATC5A (10) - L. SW <1V <1Ω 15 - 25 V > 1 MΩ
E.C↔ 4.3]
b044[E.↔ 4.4,
E.C↔ 4.4]
b045[E.↔ 4.5,
E.C↔ 4.5]
b046[E↔ 4.6,
E.C↔ 4.6]
b047[E.↔ 4.7,
E.C↔ 4.7]

b-2) Inspecting transmission input shaft speed signal system, H, L clutch (check clutch slip)
When
is displayed
Go to Troubleshooting of A-7b).
b-3) Inspecting transmission output shaft speed signal system, 1-4, R clutch (check clutch slip)
When
is displayed
Go to Troubleshooting of A-7a).

A-15 When fill switch signal is not input
(flow detector valve)
Carry out troubleshooting of A-13 b-1) Fill switch

signal. Respond to the display as follows.
5.2 ↔ 4.2
5.3 ↔ 4.3
5.4 ↔ 4.4
5.5 ↔ 4.5
5.6 ↔ 4.6
5.7 ↔ 4.7
5.8 ↔ 4.8

A-16 Short circuit in pressure control
valve solenoid is displayed
Disconnection in pressure
control valve solenoid is
displayed
• Before carrying out troubleshooting, check that all the related

connectors are properly inserted.
• Always connect any disconnected connectors before going on
to the next step.
Table 1 Table 2
Display Measurement location
Normal
7.2 ‘Trouble- Touble Measurement item value Display
Measurement Measurement Normal
9.2 shooting 1 shooting 2 location item value
Between Between Trouble Trouble Resistance
7.3 Resistance 30 - 80 Ω
ATC1 HPS 5 - 25 Ω shooting 1 shooting2 between (1) - (2)
9.3 between (1) - (2)
(9) - (19) (1) - (2) 7.1 Between
9.1 Between Resistance
Between Between ATC1
7.4 LCT between (2) - >1MΩ
ATC2 1 PS (1) - (8)
9.4 (1) - (2) chassis ground
(7) - (17) (1) - (2) (16)
Between Between
7.5
9.5
ATC2
(4) - (15)
2 PS
(1) - (2)
Resistance
b0 [E., E.C] is omitted from the Display column.
Between Between between (2) -
7.6
ATC2 3 PS >1MΩ
chassis
9.6
(3) - (13) (1) - (2) ground
Between Between
7.7
ATC2 4 PS
9.7
(8) - (18) (1) - (2)
Between Between
7.8
ATC2 RPS
9.8
(5) - (15) (1) - (2)


A-17 Fault in sensor circuits
a) Fault in torque converter oil temperature sensor is displayed


b) Fault in fuel level sensor is displayed
(It takes 30 seconds for the fuel gauge to change 1 level. Take this into account when carrying out troubleshooting).

c) Fault in cooling water temperature sensor is displayed

d) Fault in air pressure sensor is displayed
A-17 d) Related electrical circuit diagram

e) Fault in retarder brake oil temperature sensor is displayed

A-18 Warning display
a) Transmission filter clogged warning is displayed
• Before carrying out troubleshooting, check that the transmission oil filter is not clogged.

b) Tilt warning is displayed

c) Drop in radiator water level warning is displayed
• Before carrying out troubleshooting, check that the cooling water level is not low.

d) Battery charge warning is displayed
A-18 d) Related electrical circuit diagram

e) Steering oil temperature overheat warning is displayed
• Before carrying out troubleshooting, check if the steering oil temperature is high.

f) Drop in engine oil pressure warning is displayed
• Before carrying out troubleshooting, check if the engine oil pressure is low.
A-18 f) Related electrical circuit diagram

g) Rear brake oil pressure warning is displayed
• Before carrying out troubleshooting, check if the rear brake chamber has reached the end of its stroke.
A-18 g) Related electrical circuit diagram

A-19 Fault in engine oil pressure sensor is displayed

A-20 Fault in connector connection is displayed

A-21
a) Torque converter oil temperature overheat warning is displayed
• This shows that there had been an abnormal rise in the torque converter oil temperature.
• If the rise in the torque converter oil
Engine water temperature overheat warning is displayed

b)
• This shows that there has been an abnormal rise in the engine water temperature.
• If the rise in the engine water temperature is abnormal, see the engine Shop Manual.
Air pressure drop warning is displayed

c)
• This shows that there has been an abnormal drop in the air pressure.
• If the drop in the air pressure is abnormal, carry out troubleshooting H-18.
Retarder brake oil temperature overheat warning is displayed

d)
• This shows that there had been an abnormal rise in the retarder brake oil temperature.
• If the rise in the retarder brake oil temperature is abnormal, see the Operation and Maintenance Manual.

e) Engine overrun actuated is displayed
• This shows that the engine overrun prevention had been actuated to protect the transmission.
f) Engine overshoot actuated is displayed
• This shows that there has been engine overshoot (sudden spurt).

MONITOR PANEL TROUBLESHOOTING
(P - Diagnostic Flow Charts)
Method of self-diagnostic display for monitor panel and controllers . . . . . . . . . . . . . . . . . . . . . . D6-3

Action taken by self-diagnostic device and problems on truck (monitor panel) . . . . . . . . . . . . . . . . D6-3
P-1 Check pattern for wiring harnesses between modules . . . . . . . . . . . . . . . . . . . . . . . . . D6-8
P-2 Nothing on monitor panel works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-11
P-3 LH, RH module and fuel gauge do not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-12
P-4 LH, RH module and fuel gauge do not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-13
P-5 RH module does not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-14
P-6 LH module does not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D6-15
. .
P-7 Travel calculator does not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-16
P-8 Service meter display does not operate correctly . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-17
P-9 Central warning lamp does not operate, or monitor panel detects fault code [A002] . . . . . . . . . D6-18
P-10 Central warning lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-19
P-11 Alarm buzzer does not operate , or monitor panel detects failure code [A003] . . . . . . . . . . . . D6-20
P-12 Alarm buzzer continues to sound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-21
P-13 All data from shift controller (speedometer, tachometer, shift indicator, etc.) are abnormal
(nothing is displayed, or display does not change), or monitor panel detects service code [A018] . D6-22
P-14 Suspension mode power/economy mode displays are abnormal (nothing is displayed or
display does not change), or monitor panel detects service code [A016] . . . . . . . . . . . . . . . D6-23
P-15 Gauge displays are abnormal (nothing is displayed, or display does not change) . . . . . . . . . . . D6-24
P-16 Cooling water level drop caution lamp does not operate,
or monitor panel detects service code [A001] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-25
P-17 Cooling water level drop caution lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-26
P-18 Emergency steering pilot lamp does not operate, or monitor panel detects service code [A001] . . . D6-27
P-19 Emergency steering pilot lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-28
P-20 Engine oil pressure drop caution lamp does not operate, or
monitor panel detects service code [A001] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-29
P-21 Engine oil pressure drop caution lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-30
P-22 Exhaust brake pilot lamp does not operate, or monitor panel detects service code [A001] . . . . . . D6-31
P-23 Exhaust brake pilot lamp (optional) stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-32
P-24 Charging circuit fault caution lamp does not operate, or monitor panel detects service code [A001] . D6-33
P-25 Charging circuit fault caution lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-34
P-26 Transmission filter clogging caution lamp does not operate, or monitor panel detects
service code [A001] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-35
P-27 Transmission filter clogging caution lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . D6-36
P-28 Brake stroke caution lamp does not operate, or monitor panel detects service code [A001] . . . . . D6-37
D06003 Monitor Panel Troubleshooting D6-1

P-29 Brake stroke caution lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-38
P-30 Preheating switch pilot lamp does not operate, or monitor panel detects service code [A001] . . . . D6-39
P-31 Preheating switch pilot lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-40
P-32 Tilt warning lamp does not operate, or monitor panel detects service code [A001] . . . . . . . . . D6-41
P-33 Tilt warning lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-42
P-34 Body FLOAT (except FLOAT) pilot lamp does not operate,
P-35 Body FLOAT (except FLOAT) pilot lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . D6-44
P-36 Rear brake pilot lamp does not operate, or monitor panel detects service code [A001] . . . . . . . D6-45
P-37 Rear brake pilot lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-46
P-38 Parking brake pilot lamp does not operate, or monitor panel detects service code [A001] . . . . . . D6-47
P-39 Parking brake pilot lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-48
P-40 Maintenance caution lamp does not operate, or monitor panel detects service code [A001] . . . . D6-49
P-41 Maintenance caution lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-50
P-42 Steering oil temperature caution lamp does not operate,
P-43 Steering oil temperature caution lamp stays on . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-52
P-46 High beam display does not light up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-53
P-47 Turn signal lamp (right) does not light up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-55
P-48 Turn signal lamp (left) does not light up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-56
P-49 Lamp check switch does not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-57
P-50 AISS switch does not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-58
P-51 Exhaust brake switch (optional) does not operate . . . . . . . . . . . . . . . . . . . . . . . . . . D6-59
P-52 Mode change switch (1) does not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-60
P-53 Mode change switch (2) does not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-61
P-54 KPH/MPH speedometer unit selector does not operate . . . . . . . . . . . . . . . . . . . . . . . D6-62
P-55 Improper operation of all switch inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-63
P-56 Monitor panel detects service codes [A014] or [A019] . . . . . . . . . . . . . . . . . . . . . . . . D6-64
P-58 Monitor panel detects service code [A011] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D6-65
D6-2 Monitor Panel Troubleshooting D06003

MONITOR PANEL AND CONTROLLER
SELF-DIAGNOSTIC DISPLAY
1. After the key switch is turned ON, all lamps light 3. Press the caution and pilot lamp bulb check switch
for 3 seconds during the monitor self-diagnostic at the right side of the dash to verify bulb operation
test.
2. Refer to Monitor Panel Action Codes and Service
Mode Function for the displays indicating a fault
has occurred in any controller or the monitor
panel itself.
SERVICE
No. FAILURE DESCRIPTION DISPLAY CONDITIONS
CODE
Display conditions, display in service code,
1 A000 Short circuit in output
trouble data display mode.
2 A001 Short circuit in lamp output
Display when lamp check switch is pressed
3 A002 Short circuit in central warning lamp output for at least 2.5 seconds and then released.
4 A003 Short circuit in alarm buzzer output
Display in service code, trouble data display
5 A011 Fault in network
mode
Network system connection data does not
6 A012
match
7 A013 Fault in network — transmission controller
Display when lamp check switch is pressed
8 A014 Fault in network — PMC
for at least 2.5 seconds and then released.
9 A015 Fault in network — engine controller
10 A016 Fault in network — suspension controller
11 A018 Fault in model selection data
12 A019 Fault in option data
13 A021 Abnormal drop in air pressure
Engine cooling temperature overheat
14 A022
warning
Torque converter oil temperature overheat
15 A023
warning
16 A024 Brake oil temperature overheat warning
SELF-DIAGNOSTIC SERVICE CODE TABLE

ACTION TAKEN BY SELF-DIAGNOSTIC DEVICE AND PROBLEMS ON TRUCK
MONITOR PANEL SYSTEM
FAULT TROUBLESHOOTING
CODE FAULT CONDITION POSSIBLE CAUSE NOTE: Check wiring harness circuits and components listed below for
short circuit, open circuit, etc.
1. Fault between lamp (+) and monitor panel. (Refer to P-16, 18, 20, 22,
A001 Short circuit in lamp output Short circuit in output 24, 26, 28, 30, 32, 34, 36, 38, 40, 42 for troubleshooting details.)
2. Defective lamp
1. Between (+) DP08 pin 2 and WL pin 2.
Short circuit in Central
A002 Warning Lamp output
Short circuit in output 2. Defective central warning lamp
1. Between (+) DP08 pin 2 and BZ pin 2.

Short circuit in alarm buzzer
A003 output
Short circuit in output 2. Defective alarm buzzer
1. Incorrect shift controller model selection setting

Network system fault Connection data does
A012 not match
1. Between (+) DP05 pin 3, TMD pin 10, and ATC4 pin 6.
2. Between (+) DP05 pin 4, TMD pin 12, and ATC4 pin 12.
3. Between (-) DP05 pin 5, TMD pin 9, and ATC4 pin 10.
Transmission 4. Between (-) DP05 pin 5, TMD pin 11, and ATC4 pin 10.
A013 Network system fault
Controller system 5. Defective shift controller
1. Between (+) DP05 pin 3 and PMC pin 1.

A014 Network system fault PMC system 3. Between (-) DP05 pin 5 and PMC pin 3.
4. Defective PMC
1. Between (+) DP05 pin 3, SU3 pin 9, and SSP1 pin 1.

2. Between (+) DP05 pin 4, SU3 pin 13, and SSP1 pin 12.
Suspension 3. Between (-) DP05 pin 5, SU3 pin 12, and SSP2 pin 9.
A016 Network system fault
Controller 4. Between (-) DP05 pin 5, SU3 pin 14, and SSP2 pin 9.
5. Defective Suspension Controller
1. Incorrect Shift Controller model selection setting.

2. Between (+) DP05 pin 3, TND pin 10, and ATC4 pin 6.
3. Between (+) DP05 pin 4, TND pin 12, and ATC4 pin 12.
4. Between (-) DP05 pin 5, TND pin 9, and ATC4 pin 10.
A018 Network system fault Model selection data 5. Between (-) DP05 pin 5, TND pin 11, and ATC4 pin 20.
6. Defective Shift Controller.

A019 Network system fault Option data 3. Between (+) DP05 pin 5 and PMC pin 3.
4. Defective PMC.

CONDITION WHEN NORMAL CONTROLLER ACTION TRUCK SYMPTOMS
NOTE: Use a DMM to verify voltage or
WHEN FAULT IS DETECTED WHEN FAULT IS PRESENT
resistance values listed below.
1. Other mechatronics caution lamp flashes.
Lamp ON: Voltage between monitor panel
2. Displays action code. Applicable lamp always OFF.
connector and chassis ground: <0.1 volts
3. Applicable lamp forcibly turned OFF.
Central Warning Lamp ON: Voltage be-
2. Displays action code. Central Warning Lamp always OFF.
tween DP08 pin 1 and WL pin 2 <0.1 volts.
3. Central Warn. Lamp forcibly turned OFF.
Buzzer ON: Voltage between DP08 pin 2
2. Displays action code. Buzzer does not sound.
and BZ pin 2 <0.1 volts.
3. Alarm buzzer forcibly stopped.
1. Other mechatronics caution lamp flashes. If the setting is for a truck with the electronic
Shift Controller model selection setting
governor specification, engine output will
and actual mounting condition of Control-
2. Displays action code. decrease and engine speed may not
ler in network match.
increase.
1. Resistance between (+) DP05 pin 3, 1. Other mechatronics caution lamp flashes.
TMD pin 10, ATC4, pin 6 is 0 ohms.
2. Resistance between (+) DP05 pin 4, 2. Displays action code. For trucks with electronic governor
TMD pin 12, ATC4, pin 12 is 0 ohms. specification, the engine mode switching,
3. Display is fixed for all data from Transmission the engine mode selection, or AISS may
3. Resistance between (-) DP05 pin 5,
Controller (speedometer, tachometer, gauges, not work. Engine output may be reduced or
TMD pin 9, ATC4, pin 10 is 0 ohms. speed may not increase.
etc.)
TMD pin 11, ATC4, pin 10 is 0 ohms.
1. Resistance between (+) DP05 pin 3 1. Other mechatronics caution lamp flashes.
and PMC pin 1 is 0 ohms. MOM may not function properly at times.
2. Resistance between (+) DP05 pin 4 2. Displays action code. For trucks with electronic governor
and PMC pin 2 is 0 ohms. specification, the engine output may be
3. Resistance between (-) DP05 pin 5 and reduced or the speed may not increase.
PMC pin 3 is 0 ohms.
1. Resistance between (+) DP05 pin 3, 1. Other mechatronics caution lamp flashes.
SU3 pin 9, SSP1 pin 2 is 0 ohms.
2. Resistance between (+) DP05 pin 4, 2. Displays action code.
SU3 pin 13, SSP1 pin 12 is 0 ohms. In some cases, suspension control is
3. Resistance between (-) DP05 pin 5, 3. Suspension mode display does not change or inoperable.
SU3 pin 12, SSP2 pin 9 is 0 ohms. all lamps go out.
SU3 pin 14, SSP2 pin 9 is 0 ohms.
1. Shift Controller model selection setting 1. Other mechatronics caution lamp flashes.
is correct.
2. Resistance between (+) DP05 pin 3, 2. Displays action code.
TND pin 10, ATC4 pin 6 is 0 ohms. In some cases, the transmission may
3. Resistance between (+) DP05 pin 4, remain in neutral or the engine may remain
3. In addition to 1 & 2, only the speed unit, turn
TND pin 12, ATC4 pin 12 is 0 ohms. at low idle.
signal lamp, and high beam pilot lamp are
4. Resistance between (-) DP05 pin 5, displayed.
TND pin 9, ATC4 pin 10 is 0 ohms.
TND pin 11, ATC4 pin 10 is 0 ohms.
1. Resistance between (+) DP05 pin 3
and PMC pin 1 is 0 ohms. MOM may not function properly. For trucks
2. Resistance between (+) DP05 pin 4 with electronic governor specification, the
2. Displays action code. engine output may be reduced or speed
and PMC pin 2 is 0 ohms.
3. Resistance between (+) DP05 pin 5 may not increase.
and PMC pin 3 is 0 ohms.

FAULT
CODE FAULT CONDITION POSSIBLE CAUSE
TROUBLESHOOTING
A004 Fault in engine control Refer to “Electrical Troubleshooting” .

CONTROLLER ACTION TRUCK SYMPTOMS
CONDITION WHEN NORMAL
WHEN FAULT IS DETECTED WHEN FAULT IS PRESENT
1. Engine mechatronics caution lamp flashes. In some cases, the engine may not start.
2. Displays action code. Engine output may be reduced or the speed
3. Engine Stop Lamp (red) flashes. may not increase.
3. Engine Protection Lamp (blue) flashes. may not increase.
3. Engine Check Lamp (yellow) flashes. may not increase.

TROUBLESHOOTING
P-1 Check pattern for wiring harnesses between modules
NOTE: When troubleshooting the monitor panel, if the The following instructions must be followed when trou-
item in the troubleshooting flow chart or the item in the bleshooting the monitor panel and associated compo-
“remedy” column indicates “carry out check of wiring nents and wire harnesses:
harnesses between modules”, refer to the number
• Be certain all harnesses are properly inserted in
displayed in the following tables and check the female
the mating connectors.
connector of the wiring harnesses between modules.
• Before removing any harness connector, be cer-
tain the key switch is in the OFF position.
• The key switch must remain in the OFF position
when performing the following checks on the wir-
ing harnesses.
Be certain truck wheels are blocked to prevent • Visually inspect harnesses and connectors for
movement during troubleshooting procedures. physical damage, insulation cracks, pin damage
etc.
X Y
No. SIGNAL NAME
CONNECTOR PIN No. CONNECTOR PIN No.
DP11 1
A-1 1 VB (20V)
DP04 1
A-2 2 LCD TX OUT DP10 3
A-3 3 LCD TX IN DP04 4
DP10 4
A-4 4 SCK
DP04 5
DP10 5
A-5 5 LCD LOAD
DP02 DP04 6
DP10 6
A-6 6 LCD COM
DP04 7
DP10 7
A-7 7 RESET DP04 8
DP12 4
DP10 8
DP11 2
A-8 8 GND DP08 16
DP05 12
DP12 2
A-9 1 P/S DATE DP04 3
DP10
A-10 2 SHIFT/LOAD DP04 2
TABLE a. WIRING HARNESS CONTINUITY CHECK

NOTE: Circuit between “X” and “Y” connector must have continuity.

No. CONNECTOR PIN No. SIGNAL NAME
B-1 1 VB (20V)
B-2 2 LCD TX OUT
B-3 3 LCD TX IN
DP02
B-4 4 SCK
B-5 5 LCD LOAD
B-6 6 LCD COM
B-7 7 RESET
B-8 1 P/S DATE
DP10
B-9 2 SHIFT/LOAD
TABLE b. WIRING HARNESS GROUND CHECK

NOTE: Above circuits must be isolated from chassis ground.

X Y
No. SIGNAL NAME
CONNECTOR PIN No. CONNECTOR PIN No.
C-1 DP05 12
C-2 1
C-3 2
C-4 POWER 3
C-5 DP05 6 SUPPLY DP02 4
C-6 (+24V) 5
C-7 6
C-8 7
C-9 8
C-10 1
DP10
C-11 2
C-12 2
C-13 3
C-14 DP02 4
C-15 DP02 1 VB(20V) 5
C-16 6
C-17 7
C-18 1
DP10
C-19 2
C-20 3
C-21 4
C-22 DP02 5
DP02 2 LCD TX OUT
C-23 6
C-24 7
C-25 1
DP10
C-26 2
C-27 4
C-28 DP02 5
C-29 DP02 3 LCD TX IN 6
C-30 7
C-31 1
DP10
C-32 2
C-33 5
C-34 DP02 6
C-35 DP02 4 SCK 7
C-36 1
DP10
C-37 2
C-38 6
DP02
C-39 DP02 5 LCD LOAD 7
C-40 1
DP10
C-41 2
C-42 DP02 7
C-43 DP02 6 LCD COM 1
DP10
C-44 2
C-45 1
DP02 7 RESET DP10
C-46 2
C-47 DP10 1 P/S DATE DP10 2
TABLE c. HARNESS SHORT CIRCUIT CHECK
NOTE: No continuity should exist between “X” and “Y”

P-2 Nothing on Monitor Panel Operates
• Before troubleshooting, verify all connectors related to the wiring har-

nesses between the modules are properly inserted.
• Always connect any disconnected connectors before going on to the next
step.
• Refer to P-1 for Table b.

P-3 LH, RH Module and fuel gauge do not operate

step.
• Refer to P-1 for Table b.

P-4 LH, RH Module and fuel gauge do not operate

step.
• Refer to P-1 for Table a or b.

P-5 RH Module does not operate

step.
• Refer to P-1 for Table a.

P-6 LH module does not operate
step.
• Refer to P-1 for Table a and b.

P-7 Odometer does not operate

step.

P-8 Service meter does not operate correctly

step.

P-9 Central Warning Lamp does not operate, or monitor panel detects
fault code (monitor panel display) [A002]

step.

P-10 Central warning lamp stays ON

step.

P-11 Alarm buzzer does not operate. or Monitor Panel detects
fault code A003:

step.

P-12 Alarm buzzer continues to sound

step.

P-13 All data from Shift Controller (speedometer, tachometer, shift
indicator, etc.) is faulty (nothing is displayed, or display does not
change), or
Monitor Panel
detects service code
A013: or service
code A0018:
• Before troubleshooting, verify all connectors re-
lated to the wiring harnesses between the mod-
ules are properly inserted.
• Always connect any disconnected connectors be-
fore going on to the next step.

P-14 Suspension mode, power/economy mode displays are
faulty(nothing is displayed, or display does not change), or
Monitor Panel detects
service code A016:
• Before troubleshooting, verify all
connectors related to the wiring har-
nesses between the modules are
properly inserted.
• Always connect any disconnected
connectors before going on to the
next step.

P-15 Gauge displays are faulty (nothing is displayed or display does not
change)
step.
• Refer to P-1 for Tables a and b.

P-16 Cooling water level drop caution lamp does not operate, or Monitor
Panel detects service code A001:

properly inserted.
next step.

P-17 Cooling water level drop caution lamp stays ON

step.

P-18 Emergency steering pilot lamp does not operate, or monitor panel
detects service code A001:

properly inserted.
next step.

P-19 Emergency steering pilot lamp stays ON

step.

P-20 Engine oil pressure drop caution lamp does not operate, or monitor
panel detects service code
A001:
properly inserted.
next step.

P-21 Engine oil pressure drop caution lamp stays on.

step.

P-22 Exhaust brake (Optional) pilot lamp does not operate, or monitor
panel detects service code A001:
• Before troubleshooting, verify all connec-

tors related to the wiring harnesses be-
tween the modules are properly inserted.
• Always connect any disconnected connec-
tors before going on to the next step.

P-23 Exhaust brake pilot lamp stays on (Optional)

step.

P-24 Charging circuit fault caution lamp does not operate. or monitor
• Before troubleshooting, verify all connectors

related to the wiring harnesses between the
modules are properly inserted.
• Always connect any disconnected connectors
before going on to the next step.

P-25 Charging circuit fault caution lamp stays ON

step.

P-26 Transmission filter clogging caution lamp does not operate, or
monitor panel detects
service code A001:

• Always connect any disconnected con-
nectors before going on to the next step.

P-27 Transmission filter clogging caution lamp stays ON

step.

P-28 Brake stroke caution lamp does not operate, or
monitor panel detects
service code A001:
properly inserted.
next step.

P-29 Brake stroke caution lamp stays on

step.

P-30 Preheating switch pilot lamp does not work, or monitor panel

P-31 Preheating switch pilot lamp stays on.

step.

P-32 Tilt warning lamp does not operate, or monitor panel detects
service code A001:
• Before troubleshooting,
verify all connectors related
to the wiring harnesses be-
tween the modules are
properly inserted.
• Always connect any discon-
nected connectors before
going on to the next step.

P-33 Tilt warning lamp stays on.

step.

P-34 Body FLOAT (except FLOAT) pilot lamp does not operate, or
monitor panel detects service code A001:


P-35 Body FLOAT (except FLOAT) pilot lamp stays on.

step.

P-36 Rear brake pilot lamp does not work, or monitor panel detects
service code A001:
• Before troubleshooting, verify all con-
nectors related to the wiring harnesses
between the modules are properly in-
serted.
nectors before going on to the next
step.

P-37 Rear brake pilot lamp stays on

step.

P-38 Parking brake pilot lamp does not operate, or monitor panel detects
service code A001:

P-39 Parking brake pilot lamp stays on

step.

P-40 Maintenance caution lamp does not operate, or monitor panel


P-41 Maintenance caution lamp stays on

step.

P-42 Steering oil temperature caution lamp does not operate, or monitor
• Before troubleshooting, verify all connectors re-

lated to the wiring harnesses between the mod-
ules are properly inserted.
• Always connect any disconnected connectors be-
fore going on to the next step.

P-43 Steering oil temperature caution lamp stays on
step.

P-46 High beam display does not light up
step.
Refer to following page for related electrical circuit diagram

P-46 High beam display does not light up (Continued from previous
page)

P-47 Turn signal lamp (right) does not light up
• Before troubleshooting, verify all connectors related to the wiring harnesses be-

P-48 Turn signal lamp (left) does not light up
• Before troubleshooting, verify all connectors related to the wiring harnesses between the

P-49 Lamp check switch does not operate

P-50 AISS switch does not operate

P-51 Exhaust brake switch does not operate (Optional)

P-52 Mode change switch (1) does not operate

P-53 Mode change switch (2) does not operate

P-54 KPH/MPH speedometer unit selector does not operate

P-55 Improper operation of all switch inputs

P-56 Monitor panel detects service
codes A014 or A019:

P-58 Monitor panel detects service code A011:
• The monitor panel saves trouble data for problems detected as [A013], [A014], [A015], [A016], [A018], or [A019]
together as service code [A011].
• If [A013], [A014], [A015], [A016], [A018], or [A019] are currently being detected, carry out repairs according to
the respective troubleshooting.
• If [A013], [A014], [A015], [A016], [A018], or [A019] are not currently being detected, the system has been reset
so the condition is normal.
• The monitor panel saves trouble data for problems detected as [A001], [A002], or [A003] together as fault code
[A000].
• If [A001], [A002], or [A003] are currently being detected, carry out repairs according to the respective troubleshoot-
ing.
• If [A001], [A002], or [A003] are not currently being detected, the system has been reset so the condition is normal.

NOTES

ENGINE ELECTRONIC DIAGNOSTIC SYSTEM
The following information relates to the engine elec- When the keyswitch is turned
tronic diagnostic system. The controls are located on “On”, the lamps (7,8, 9) should
the Operator’s center console (items 7, 8, 9, 11, & 12, illuminate for about 2 seconds
Figure 7-1). and then turn “Off”, if no
“faults” are detected in the sys-
If an abnormal engine condition develops, the control
tem. This is a system lamp test.
system will record a “fault” code associated with that
condition. By use of a series of indicator lamps and
switches, the system will display the numerical “fault”
code. If a light remains
ON, or if a light
Release Button FLASHES, then
act i ve “ fault s”
have been de-
tected by the sys-
t e m an d t he
en gin e should
not be started un-
til the condition
h as b een cor-
rected.
Refer to DETERMING “FAULT” CODES.
During engine operation, if a “fault” is detected in the

system, a light associated with that condition will turn
“ON” and stay on for “Warning faults”, or it will turn
“ON” and “FLASH” for more severe faults that can
affect engine operation and require immediate atten-
tion.
FIGURE 7-1. CENTER CONSOLE

• “Warning” faults (light ON) are ones that require
attention in the near future, but in most conditions
1. Transmission Range Selector (Shift Lever) will not greatly affect performance.
2. Shift Limiter Switch
3. Power Mode Selector Switch • “Severe” faults (light FLASHING) are ones that
4. Emergency Steering Switch require immediate attention, because the engine
5. Emergency Brake Lever could be significantly affected.
6. Parking Brake Valve Lever Active fault conditions MUST be corrected as soon
7. Engine Shutdown Warning Light as possible.
8. Engine Maintenance Light
9. Engine Maintenance Light
10. This space not currently used.
11. Engine Fault Code Switch
12. Engine Diagnostic Switch
D07002 Engine Electronic Diagnostic System D7-1

Engine Shutdown Light (Stop Engine) Fault Check Switch (11, Figure 7-1)
(7, Figure 7-1)
This Fault Check switch, when moved to the
When illuminated, this red engine “ON” (down) position, may be used to acti-
shutdown light vate the engine electronic control system
indicates that a diagnostic codes. When the system detects
serious engine a “fault” and one of the indicator lamps (7,
problem exists. 8, 9) illuminates as previously described,
this switch will permit determination of the
kind of “fault(s)” detected.
The “fault” can be engine disabling. Stop the truck in

a safe area, as soon as possible. Shutdown the engine Fault Scroll Switch (12, Figure 7-1)
and notify Maintenance personnel immediately.
This Fault Scroll switch may be used to
scroll through the recorded faults held in
memory.
Engine Maintenance Light (Check Engine)
It will display only active fault codes.
(8, Figure 7-1)
To display the next active fault code, move the switch
This amber/yellow light, when illu-
lever to the “up” position momentarily and release
minated, indicates an engine “fault”
(switch is spring-loaded to the center “OFF” position).
exists. Current engine operation
may proceed, but the machine Activating the switch again will advance to the next
should be scheduled for check- fault code, etc. Once all active fault codes have been
out/repair as soon as practical. displayed, the fault code display sequence will be
repeated, starting from the first fault code.
Moving the switch lever to the “down” position momen-
tarily and releasing, permits the system to scroll (as
Engine Maintenance Light (Protect Engine
described above) backwards through the fault “list”.
(9, Figure 7-1)
This blue engine maintenance

light, when illuminated, indicates
an “out-of-range” condition exists
within the fuel temperature, cool-
ant, oil, or intake air system(s) of
the engine.
The light may show initially as a constant “On”, but will

go to “flashing On”, if the condition is allowed to get
worse. Serious engine damage will occur if operation
is continued without correcting the “fault”.
D7-2 Engine Electronic Diagnostic System D07002

Determing “Fault” Codes EXITING THE DIAGNOTICS MODE
1. To determine an active “fault”, turn the keyswitch
to the “OFF” position and wait until the engine Starting the engine,
completely stops. o r t u rn in g th e
keyswit ch to t he
OFF position, will
2. Turn keyswitch to “ON” position (engine NOT EXIT the diagnos-
running) and hold the Fault Check switch (11) in tics fault flash mode.
the “ON” position.
If active fault codes have been determined as de-

scribed previously, refer to the appropriate Komatsu
engine manual.
3. If there is an active fault:

a. The amber/yellow Engine Maintenance light (8)
will flash once.
b. There will be a 1-2 second pause, and then the
red Engine Shutdown light (7) will flash out the
three digit diagnostic code.
Each digit is indicated with up to nine light
flashes for each digit. There is a short pause
between each digit of the fault code.
c. After all three digits are flashed, the yellow lamp
will flash once, and then the red lamp will
repeat the same fault code sequence as be-
fore.
4. The system will continue to flash the same fault

code until the Fault Scroll Switch (12) is activated
again.

Fault Code Information (T01-001)
FAULT
PID (P) SPN
CODE REASON EFFECT (Only when fault code is active)
SID (S) FMI
LAMP
Error internal to the Electronic Control Module (ECM) related to
111 629
S254 the memory or hardware or internal microprocessor Engine will not start.
Red 12
communications failures.
No action by the ECM is taken.
113 635 More than 6.2 amps detected at timing sleeve actuator circuit The engine may have low power outputs,
S020
Yellow 3 pin 6 of the engine harness. loud combustion noise, and produce black
smoke.
114 635 Less than 1.0 amp is detected at the timing sleeve actuator No action by the ECM is taken.
S020
Yellow 4 circuit pin 6 of the engine harness. Engine emits white smoke and loses power.
122 102 More than 4.72 volts is detected at the intake manifold air
P102 Engine power derate to no-air setting.
Yellow 3 pressure sensor signal pin 45 of the engine harness.
123 102 Less than 0.33 volts is detected at the intake manifold air
P102 Engine power derate to no-air setting.
131 091 More than 4.20 volts is detected at the throttle position signal Calibration-dependent power and speed
P091
Red 3 or 4 pin 30 of the OEM interface harness. derate.
132 091 Less than 0.13 volts is detected at throttle position signal pin 30 Calibration-dependent power and speed
P091
Red 3 or 4 of the OEM interface harness. derate.
133 091 More than 4.82 volts is detected at the remote throttle position Calibration-dependent power and speed
P091
Red 3 or 4 signal pin 9 of the OEM interface harness. derate.
134 091 Less than 0.12 volts is detected at the remote throttle position Calibration-dependent power and speed
P091
Red 3 or 4 signal pin 9 of the OEM interface harness. derate.
135 100 More than 4.88 volts is detected at oil pressure sensor signal
P100 Engine protection for oil pressure is disabled.
Yellow 3 or 4 pin 33 of the engine harness.
141 100 Less than 0.31 volts is detected at the oil pressure sensor
P100 Engine protection for oil pressure is disabled.
Yellow 3 or 4 signal pin 33 of the engine harness.
Low oil pressure has been detected. Voltage signal at oil
pressure signal pin 33 of the engine harness indicates oil Depending upon calibration, progressive
143 100
P100 pressure lower than 69 kPa (10 psi) at engine speeds less than power derate and engine shutdown with
Blue 1
800 rpm; 155 kPa (22.5 psi) at 1200 rpm; 241 kPa (35 psi) increasing time after alert.
above 1600 rpm.
144 110 More than 4.95 volts is detected at the coolant temperature Engine protection for coolant temperature is
P110
Yellow 3 signal pin 23 of the engine harness. disabled.
145 110 Less than 0.21 volts is detected at the coolant temperature Engine protection for coolant temperature is
P110
Yellow 4 signal pin 23 of the engine harness. disabled.
147 091 A frequency of less than 150 Hz has been detected at the Calibration dependent power and speed
P091
Red 8 frequency throttle signal, pin 14 of the engine harness. derate.
A frequency of more than 400 Hz has been detected. Voltage
148 091 Calibration dependent power and speed
P091 signal pin 22 indicates coolant temperature above 100°C
Red 8 derate.
(212°F).
Calibration dependent progressive power and
151 110 High coolant temperature has been detected. Voltage signal at
P110 speed derated and engine shutdown as
Blue 0 coolant temperature above 100°C (212°F).
temperature increases over thresholds.
153 105 More than 4.88 volts is detected at intake manifold air Engine protection for intake manifold air
P105
Yellow 3 temperature signal pin 34 of the engine harness. temperature
154 105 Less than 0.08 volts is detected at intake manifold air Engine protection for intake manifold air
P105
Yellow 4 temperature signal pin 34 of the engine harness. temperature
High intake air manifold temperature has been detected. Depending on the calibration, a progressive
155 105
P105 Voltage signal at intake manifold air temperature signal pin 34 power and speed derate and engine shutdown
Blue 0
indicates intake manifold air temperature above 104°C (220°F) as the temperature increases over thresholds.
166 733 The rack position sensor indicates that the rack position is
S024 No action by the ECM is taken.
Yellow 3 greater than a calibrated threshold.

FAULT
PID (P) SPN
SID (S) FMI
LAMP
172 638 Fuel control rack is stuck in a position commanding
S023 Engine shutdown
Red 6 excessive fueling to the engine
173 638 Fuel control rack is stuck in a position providing adequate,
S023 No action is taken by the ECM.
Yellow 7 or less than adequate, fueling to the engine.
184 609 Module identification at powerup will fail, both
S233 Primary and/or secondary ECM identification error.
Red 2 modules will run as slaves.
221 108 More than 4.78 volts is detected at the ambient air
P108 No action is taken by the ECM.
Yellow 3 or 4 pressure signal pin 32 of the engine harness.
222 108 Less than 0.20 volts is detected at the ambient air pressure
P108 No action is taken by the ECM.
Yellow 4 signal pin 32 of the engine harness.
231 109 More than 4.72 volts is detected at the coolant pressure
P109 Engine protection for coolant pressure is disabled.
Yellow 3 sensor signal pin 24 of the engine harness.
232 109 Less than 0.33 volts is detected at the coolant pressure
P109 Engine protection for coolant pressure is disabled.
Low coolant pressure has been detected. Voltage signal at
coolant pressure siganl pin 24 of the engine harness Calibration dependent progressive power and
233 109
P109 indicates coolant pressure lower than 28 kPa (4 psi) at 800 speed derate and engine shutdown with
Blue 1
rpm; 41 kPa (6psi) at 13000 rpm; 76 kPa (11psi) at 1800 increasing time after alert.
rpm kPa (15 psi) above 2100 rpm.
The EHAB (fuel shutoff valve) is de-energized,
234 190 Engine speed signals on pin 17 of the engine harness (closed). The EHAB (fuel shutoff valve) is
P190
Red 0 indicate an engine speed greater than 2650 rpm. reenergized (opened) when engine speed falls
below 2130 rpm.
Low coolant level has been detected. Voltage signal on Calibration-dependent progressive power and
235 111
P111 the coolant level signal pin 37 of the engine harness speed derate, and engine shutdown with
Blue 1
indicates low radiator coolant level in the vehicle. increasing time after alert.
252 098 Low voltage detected at the lubricating oil level sensor
P098 No action taken by the ECM.
Yellow 2 supply pin 49 of the engine harness.
253 98 Voltage signal on the oil level signal pin 49 of the engine
P098 Engine will not start.
Blue 1 harness indicates low oil level in the engine.
No action is taken by the ECM. Low voltage to the
254 632 Less than 16.5 volts detected at fuel shutoff valve solenoid EHAB will cause it to stop fuel flow to teh
S017
Red 4 supply pin 43 of the engine harness. corresponding pump, and shut down that engine
bank.
259 632 ECM commands rack position to xero, which stops
S017 EHAB (fuel shutoff valve) is open and will not close.
Red 7 fueling corresponding engine bank.
342 630
S253 The primary and secondary ECM calibrations do not match. Engine will not start.
Red 13
343 629
S254 Microprocessor communication error internal to the ECM. Variable; performance will or will not be affected.
Yellow 12
Power down data (which includes maintenance
346 630
S253 ECM power down internal data store error. monitoring, current ECM/engine delta times, and
OFF 12
past fault data) are lost.
Very low oil pressure has been detected. Voltage signal at
oil pressure signal pin 33 of the engine harness indicates Calibration dependent progressive power and
415 100
P100 oil pressure lower than 800 rpm; 121 kPa (17.5 psi) at speed derate and engine shutdown with
Blue 1
1200 rpm; 207 kPa (30 psi) at engine speeds greater than increasing time after alert.
1600 rpm.
Voltage detected simultaneously on both the coolant level
422 111
P111 high and low signal pins 27 and 37 of the OEM interface No action taken by the ECM.
Yellow 2
harness, or no voltage detected on either pin.
Voltage detected simultaneously on both the idle validation,
431 091,607
P091 off-idle and idle-signal pins 25 and 26 of the OEM interface None on performance.
Yellow 2 or 4
harness.

FAULT
PID (P) SPN
SID (S) FMI
LAMP
Voltage detected at idle validation on idle signal pin 26 of
the OEM harness when voltage at accelerator position
signal pin 30 of the OEM harness indicates pedal is not at
432 091 Engine will not respond to accelerator.
P091 idle, or voltage detected at idle validation off-idle signal pin
Red 13 Engine will idle only.
25 of the OEM harness when voltage at accelerator
position signal pin 30 of the OEM harness indicates pedal
is at rest.
441 168 Less than 9 volts battery voltage detected at the engine ECM voltage supply approaching a level at which
P168
Yellow 1 harness. unpredictable operation will occur.
442 168
P168 More than 34 volts battery voltage detected at ECM. ECM damage will occur.
Yellow 0
524 113 Voltage detected at pin 22 of the engine harness is out of Droop setting defaults to switch position "1" (or
P113
Yellow 2 range. normal) preprogrammed droop
527 702 Less than 17 volts detected at solenoid supply pin 41 of the
S040 No action is taken by the ECM.
Yellow 3 engine harness.
528 093 Voltage detected at pin 39 of the OEM interface harness is Torque curve setting defaults to switch position 2 (or
P093
Yellow 3 out of range. lowest) preprogrammed torque curve.
No voltage detected simultaneously on both the idle
551 091
P091 validation off-idle and idle-signal pins 25 and 26 of the Engine will default to zero percent throttle.
Yellow 2 or 4
OEM interface harness.
High crankcase blowby pressure has been detected. Calibration dependent progressive power and
555 101
P101 Voltage signal at blowby pressure signal pin 25 indicates speed derate and engine shutdown with increasing
Blue 0
blowby pressure above 368 mm H20 (14.5 in H20). time after alert.
719 101 More than 4.94 volts detected at the blowby pressure
P030 Engine protection for blowby flow rate is disabled.
729 101 Less than 0.29 volts detected at the crankcase blowby
P101 Engine protection for blowby flow rate is disabled.

ELECTRICAL SPECIFICATIONS
This diagram is provided as a diagnostic tool for trained, experienced technicians only. Improper trouble-
shooting or repair can result in severe personal injury or death or property damange. See important
instructions in the Shop Manual.
DATA LINK ALL SHORTS TO GROUND

Resistance between positive/negative wires 55 to 65 No short circuit if more than 100 k
ALL CONTINUITY CHECKS SHORT CIRCUIT TO EXTERNAL VO

No open circuit if less than 10 No short circuit if less than 1.5 VDC
EHAB (FUEL SHUTOFF VALVE) RACK ACTUATOR

Internal Resistance 38.5 to 43.5 Coil Resistance
7.0 to 9.0
ESS/EPS VOLTAGE RANGES
Low Signal
Less than 0.4 VDC
High Signal
Greater than 4.5 VDC
SENSOR SPECIFICATIONS
OIL OR COOLANT PRESSURE SENSOR AMBIENT AIR PRESSURE SENSOR

Torque = 14 N*m [10 ft - lb] Torque = 23 N*m [17 in - lb]
Pressure (kPa) Pressure (psi) Voltage (V) mmHg inHg Voltage (v)
0 0 0.39-0.58 259 10.2 1.67-1.99
172 25 1.39-1.61 517 20.4 3.05-3.29
344 50 2.39-2.61 621 24.4 3.58-3.82
517 75 3.39-3.61 776 30.5 4.38-4.62
689 100 4.39-4.61
INTAKE MANIFOLD PRESSURE SENSOR ALL TEMPERATURE SENSORS

Torque = 14 N*m [10 ft - lb] Torque = 14 N*m [10 in - lb]
Pressure (kPa) Pressure (psi) Voltage (V) Altitude (m) Altitude (ft) Voltage (v)
0 0 0.41-0.59 104 15 0.43-0.57
69 10 1.21-1.39 586 85 1.62-1.76
138 20 2.01-2.19 931 135 2.48-2.60
207 30 2.81-2.99 1276 185 3.32-3.46
276 40 3.61-3.79 1620 235 4.15-4.33
345 50 4.41-4.59 1725 250 4.41-4.59

NOTES

HYDRAULIC AND MECHANICAL SYSTEMS TROUBLESHOOTING
H-1 Truck does not move . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-2

H-2 Truck does not travel smoothly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-4
H-3 Lock-up clutch cannot be disengaged . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-4
H-4 Excessive shock when starting or shifting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-4
H-5 Transmission does not shift up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-5
H-6 Truck lacks power or speed when moving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-6
H-7 Time lag is excessive when starting or shifting gear . . . . . . . . . . . . . . . . . . . . . . . . . . D8-10
H-8 Torque converter oil temperature is high . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-12
H-9 Torque converter oil pressure is high . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-13
H-10 Front brakes are ineffective, or effective only on one side . . . . . . . . . . . . . . . . . . . . . . . D8-14
H-11 Rear brakes are ineffective, or effective on one side only . . . . . . . . . . . . . . . . . . . . . . . D8-15
H-12 Steering wheel is difficult to turn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-16
H-13 Steering wheel inoperative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-17
H-14 Steering wheel vibrates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-17
H-15 Hoist cylinder lacks lifting force (lifting speed) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-18
H-16 Hoist cylinders do not operate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-20
H-17 Excessive dump body hydraulic drift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-22
H-18 Air pressure does not increase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D8-23
D08002 Hydraulic and Mechanical Systems Troubleshooting D8-1

H-1 Truck does not move
Checks before troubleshooting
Ask the operator the following questions: • Is the transmission oil level correct?
• Did the problem suddenly happen? • Is the torque converter, transmission input
YES = Internal seizure, damage shaft broken? (Check with the transmission
• When this happened, was there any abnor- input shaft speed sensor.)
mal noise? • Is the drive shaft broken?
YES = Broken part • Are the brakes dragging?
No. PROBLEM CAUSE REMEDY

a. Clogged strainer Clean
1 Abnormal noise from between pump and filter
b. Air sucked in at suction side of pump Repair
a. Defective pump Replace
b. Drop in pressure of main relief valve (torque converter Repair or
Truck does not start in any gear range. valve) replace
2
(Item No. 1 is normal)
c. Internal transmission damage Replace
d. Internal torque converter damage Replace
e. Defective speed sensor Replace
a. Defective ECMV Replace
b. Defective transmission clutch seal ring, groove Replace
c. Seized transmission clutch Replace
3 Truck starts normally in certain gear range
d. Defective speed clutch (oil leak) Replace
e. Defective shaft seal ring in speed clutch circuit Replace
f. Internal transmission damage Replace
g. Defective speed sensor Replace
4 Truck does not move when oil temperature rises b. Defective transmission clutch seal ring, groove Replace
c. Defective speed clutch (oil leak) Replace
d. Defective shaft seal ring in speed clutch circuit Replace
Low at every gear b. Air sucked in at suction side of pump Repair
5
range
c. Drop in pressure of main relief valve (torque converter Repair or
valve) replace
a. Defective ECMV Replace
Transmission oil
pressure is low Becomes lower at b. Defective transmission clutch seal ring, groove Replace
6
certain speed range
c. Defective speed clutch (oil leak) Replace
d. Defective shaft seal ring in speed clutch circuit Replace
Indicator is a. Clogged strainer Clean
unstable and
7
fluctuates b. Air sucked in at suction side of pump Repair
excessively
When pressure pickup port plug is removed and
8 a. Pump does not turn (defective PTO) Replace
engine is cranked, no oil comes out.
9 Modulation pressure is abnormal a. Defective ECMV Replace
a. Drop in pressure of main relief valve (torque converter Repair or
10 Hydraulic pressure at pump outlet port is low
valve) replace
D8-2 Hydraulic and Mechanical Systems Troubleshooting D08002

CLUTCH
GEAR L 4th
H 3rd 2nd 1st R
RANGE (rotating) (rotating)
R
N
F1
F2
F3
F4
F5
F6
F7
CLUTCH COMBINATION TABLE

H-2 Truck does not travel smoothly (truck jerks)
• Transmission hunts.
• Lock-up lamp flashes.
CAUSE REMEDY
Drop in main relief pressure
Refer to H-6
Worn clutch seal ring
H-3 Lock-up clutch cannot be disengaged (engine stalls)

• Is the level in transmission case correct?

a. Improper operation of lock-up solenoid valve Replace
1 Lock-up pressure does not drop to “0” Clean or
b. Improper operation of lock-up valve
Replace
Lock-up clutch is not disengaged even when lock-up
2 a. Seized lock-up clutch Replace
pressure is “0”
3 Operation of lock-up valve is normal a. Improper operation of lock-up solenoid valve Replace
Clean or
4 Operation of lock-up solenoid valve is normal a. Improper operation of lock-up valve
Replace
H-4 Excessive shock when starting to move or shifting

Determining Standard
There is some shock, but it is difficult to determine if the shock is excessive or not, so determine if it is excessive in
the following cases:
• It is clear that the shock has suddenly become excessive.
• The shock is excessive compared with other trucks of the same model.
Cause
• Improper operation due to dirt in the ECMV pressure control valve spool or flow detector valve spool. Im-
proper operation of the of the ECMV proportional solenoid.
• Improper operation due to dirt in the in the pressure control valve spool.

H-5 Transmission does not shift up
a. Does not shift up
• Shifts on downhill slopes.
CAUSE REMEDY
Slipping or damaged torque converter lock-up clutch Repair or replace
NOTE: The above is the most probable cause, but for details, see “Torque converter lock-up does not engage”.
b. Does not shift up
CAUSE REMEDY
Improper operation of ECMV for clutch which does not shift up Clean, repair, or replace
Defective piston seal ring, defective groove for clutch which does not shift up Replace
Drop in main relief pressure Adjust, clean, repair, or replace
CLUTCH
GEAR L 4th
H 3rd 2nd 1st R
R
N
F1
F2
F3
F4
F5
F6
F7

H-6 Truck lacks power or speed when moving
a. Problems at all gear ranges
• Is the oil level in the transmission case correct?
• Is there any external oil leakage from the piping or valve connections?
• Is the parking brake, service brake, or retarder dragging?
Checking for problems
• Engine high idle speed
• Torque converter stall speed
• Truck speed
• Transmission clutch pressure
• Torque converter lock-up pressure
• Main relief pressure.

b. Drop in pressure of main relief valve (torque converter Adjust, repair, or
valve) replace
2 Torque converter stall speed is high c. Defective operation of torque converter relief valve, Adjust or
weak spring replace
d. Cooler, piping beyond torque converter outlet port Repair or
damaged replace
e. Internal torque converter damage (turbine rivet broken) Replace
a. Drop in engine performance Repair
3 Torque converter stall speed is low
b. Defective torque converter stator clutch Replace
Low at every gear b. Defective pump Replace
4
range
c. Drop in pressure of main relief valve (torque converter Adjust, repair, or
valve) replace
Transmission pressure is low Indicator is a. Clogged strainer Clean
unstable and
5
fluctuates b. Air sucked in at suction side of pump Repair
excessively
Low after entering
6 torque converter a. See “Torque converter lock-up does not engage”
lock-up
a. Defective operation of torque converter relief valve, Adjust or
Hydraulic pressure at torque converter inlet port is weak spring replace
7
low (items 4 - 6 normal) b. Cooler, piping beyond torque converter outlet port Repair or
damaged replace
Hydraulic pressure at torque converter outlet port is a. Cooler, piping beyond torque converter outlet port Repair or
8
low (item 7 normal) damaged replace
Iron and aluminum particles stuck to strainer and a. Defective torque converter stator clutch Replace
9
drain plug of transmission case. b. Internal torque converter damage (turbine rivet broken) Replace
a. Drop in pressure of main relief valve (torque converter Adjust, repair, or
10 Hydraulic pressure at pump outlet port is low
valve) replace
11 When oil temperature rises, oil pressure drops a. Defective pump Replace

b. Torque converter lock-up does not engage
Ask the operator the following questions:

• Did the problem suddenly happen?
YES = Internal seizure, damage
• When this happened, was there any abnormal noise?
Yes = Broken part

• Is there any external oil leakage?
• Is current flowing to the lock-up solenoid? (Check using a voltmeter.)
Checking for problems:
• Main relief pressure
• Lock-up oil pressure
• Truck speed

Repair or
a. Drop in main relief valve pressure
replace
1 Main relief pressure is low
Repair or
b. Defective lock-up solenoid
replace
Repair or
a. Improper operation of lock-up solenoid valve spool
replace
2 With item 1 normal, lock-up pressure is low or “0” Repair or
b. Improper operation of lock-up valve spool
replace
c. Cracked lock-up clutch case Replace
Solenoid is normal in item 2 (proper continuity, no Repair or
3 a. Improper operation of lock-up valve spool
short circuit) replace
Solenoid is defective in item 2 (no continuity or short Repair or
4 a. Improper operation of lock-up solenoid valve spool
circuit) replace
a. Worn lock-up clutch piston seal ring Replace
5 With items 1 - 4 normal, lock-up pressure is low
b. Worn lock-up clutch disc Replace
6 Oil pressure is normal in item 5 a. Worn lock-up clutch disc Replace
7 Lock-up pressure is low and main pressure is also low a. Cracked lock-up clutch case Replace
Repair or
a. Improper operation of lock-up valve spool
8 Lock-up requires excessive time to engage replace
b. Worn lock-up clutch piston seal ring Replace

c)-1 Problems in some gear ranges (troubleshooting without using shift checker)

• Is the oil level in the transmission case cor-
rect?
• Is the parking brake, service brake, or re-
tarder dragging?
• Truck travel speed
TRANSMISSION
CONTROLLER
SELF-DIAGNOSTIC
DISPLAY
a. 2nd clutch disc worn or seized, seal ring worn Replace
(1) F1 is normal, but F2 is defective 2.5 3.5 4.5 4.5
1 b. Improper operation of 2nd clutch ECMV Replace
Returns to normal when replaced
(2) a. Improper operation of 2nd clutch ECMV Replace
with any ECMV except 2nd.
a. 1st clutch disc worn or seized, seal ring worn Replace
(1) F2 is normal, but F1 is faulty 2.4 3.4 4.4 5.4
2 b. Improper operation of 1st clutch ECMV Replace
(2) a. Improper operation of 1st clutch ECMV Replace
with any ECMV except 1st.
F1 and F2 are normal, but F3 is a. H clutch disc worn or seized, seal ring worn Replace
(1) 2.2 3.2 4.2 5.2
faulty b. Improper operation of H clutch ECMV Replace
3
(2) a. Improper operation of H clutch ECMV Replace
with any ECMV except H.
F1, F2, and F3 are normal, but F4 a. 3rd clutch disc worn or seized, seal ring worn Replace
(1) 2.6 3.6 4.6 5.6
is faulty b. Improper operation of 3rd clutch ECMV Replace
4
(2) a. Improper operation of 3rd clutch ECMV Replace
with any ECMV except 3rd.
a. 4th clutch disc worn or seized, seal ring worn Replace
(1) F1 - F5 are normal, but F6 is faulty 2.7 3.7 4.7 5.7
5 b. Improper operation of 4th clutch ECMV Replace
(2) a. Improper operation of 4th clutch ECMV Replace
with any ECMV except 4th.
F3, F5, and F7 are normal, but a. L clutch disc worn or seized, seal ring worn Replace
(1) 2.3 3.3 4.3 5.3
others are faulty b. Improper operation of L clutch ECMV Replace
6
(2) a. Improper operation of L clutch ECMV Replace
a. R clutch disc worn or seized, seal ring worn Replace
(1) Only R is faulty 2.8 3.8 4.8 5.8
7 b. Improper operation of R clutch ECMV Replace
(2) a. Improper operation of R clutch ECMV Replace
NOTE:
> Remove all dirt and mud from around the ECMV, and clean it before replacing.
> After replacing, tighten ECMV mounting bolts to 2.8 - 3.5 kg.m (20 - 25 ft. lbs) torque

CLUTCH
GEAR L 4th
H 3rd 2nd 1st R
R
N
F1
F2
F3
F4
F5
F6
F7

H-7 Time lag is excessive when starting to move, or shifting gear
• Is there any external oil leakage from the piping or valve joints?
• Is operation of control valve normal?
• Refer to “Standard Value Tables” to check if the time lag is actually excessive.

1 Noise comes from pump
There is a time lag when transmission is placed in
2 Repair or
any speed range b. Defective pump
replace
a. 2nd clutch disc worn or defective seal ring, worn groove Replace
3 F1 is normal, but there is time lag when shifting to F2
b. Improper operation of 2nd clutch ECMV Replace
a. 1st clutch disc worn or defective seal ring, worn groove Replace
4 F2 is normal, but there is time lag when shifting to F1
b. Improper operation of 1st clutch ECMV Replace
F1 and F2 are normal, but there is time lag when a. H clutch disc worn or defective seal ring, worn groove Replace
5
shifting to F3 b. Improper operation of H clutch ECMV Replace
F1, F2 and F3 are normal, but there is time lag when a. 3rd clutch disc worn or defective seal ring, worn groove Replace
6
shifting to F4 b. Improper operation of 3rd clutch ECMV Replace
a. Speed clutch oil leak Repair
F1 - F5 are normal, but there is time lag when b. Defective shaft seal ring in speed clutch circuit Replace
7
shifting to F6
c. 4th clutch disc worn or defective seal ring, worn groove Replace
d. Improper operation of 4th clutch ECMV Replace
F3, F5 and F7 are normal, but there is time lag when a. L clutch disc worn or defective seal ring, worn groove Replace
8
in other speed ranges b. Improper operation of L clutch ECMV Replace
a. R clutch disc worn or defective seal ring, worn groove Replace
9 There is a time lag in R
b. Improper operation of R clutch ECMV Replace
Transmission modulating pressure low when placed
10 Repair or
in any gear range c. Defective pump
replace
Repair or
d. Drop in main relief valve pressure
replace
Torque converter oil temperature goes above b. Air sucked in at suction side of pump Repair
11
operating range
Repair or
c. Defective pump
replace

CLUTCH
GEAR L 4th
H 3rd 2nd 1st R
R
N
F1
F2
F3
F4
F5
F6
F7

H-8 Torque converter oil temperature is high
• Does the oil temperature go up when torque converter is stalled and go down when torque converter is
not stalled?
Yes = Normal (incorrect selection of speed range)
• Is oil level in transmission or steering case normal?
• Use “Standard Value Table” to determine if torque converter oil temperature is actually high.
> NOTE: If oil temperature is normal but oil temperature gauge on truck goes above operating range, the
gauge is defective and should be replaced.

Pump makes abnormal noise when oil temperature is a. Clogged strainer Clean
1
low b. Air sucked in at suction side of pump Repair
a. Oil leakage inside torque converter (defective seal ring, Repair or
2 High idle and low idle speeds are low
loose bolt, crack in pump, turbine) replace
3 Torque converter outlet port oil pressure is low
Repair or
4 Torque converter inlet port oil pressure is low a. Defective torque converter relief valve
replace
5 Transmission modulating pressure is low b. Air sucked in at suction side of pump Repair
c. Defective pump Replace
6 Excessive leakage inside torque converter
NOTE: If troubleshooting shows all above items are normal, the pump
filter is clogged and should be replaced.

H-9 Torque converter oil pressure is low
• Is oil level in transmission case correct?
• Is there any external oil leakage from the piping or valve joints?
• Pump outlet port oil pressure

a. Clogged hydraulic pump suction strainer or suction of
1 Noise comes from pump Clean
air into circuit
2 Oil pressure is low between pump and relief valve a. Defective hydraulic pump Repair or replace
a. Drop in pressure of torque converter relief valve Repair or replace
3 Torque converter inlet port pressure is low
b. Excessive leakage inside torque converter Repair or replace
Transmission and lock-up pressures are normal, but
4 a. Excessive leakage inside torque converter Repair or replace
torque converter inlet pressure is low
When pressure of torque converter relief valve is
5 a. Drop in pressure of torque converter relief valve Repair or replace
raised, relief pressure becomes high

H-10 Front brakes are ineffective, or effective only on one side
• Is oil level in the brake tank correct?
• Is there air in the brake oil?
• Is there external oil leakage between the brake chamber and wheel cylinder?
• Is the air pressure within the operating range?
• Air pressure
• Brake chamber outlet port pressure

a. Defective brake valve Repair or replace
Oil pressure at master cylinder outlet port is low b. Defective relay valve Repair or replace
1
(outlet port hose disconnected) c. Clogged, crushed tube between relay valve and brake
Repair or replace
chamber
d. Defective brake chamber seal Replace
a. Defective brake chamber seal Replace
2 Air pressure at brake chamber inlet port is normal b. Clogged, crushed tube between relay valve and brake
Repair or replace
chamber
3 Air pressure at brake chamber inlet port is low b. Defective relay valve Repair or replace
c. Clogged, crushed tube between relay valve and brake
Repair or replace
chamber
4 Air leakage from brake chamber a. Defective brake chamber seal Replace
Items 1-4 are normal, but there is lack of hydraulic a. Clogged, crushed tube between relay valve and brake
5 Repair or replace
pressure in wheel cylinder chamber
Items 1-5 are normal, but brake is ineffective or
6 a. Excessive brake disc wear Replace
braking effect is poor

H-11 Rear brakes are ineffective, or effective on one side only
• Is there air in the brake oil circuit?
• Is the transmission oil level correct?
• Is there external oil leakage between the brake chamber and brake?
• Is the air pressure within the operating range?
• Air pressure
• Brake chamber outlet port pressure

b. Defective relay valve Repair or replace
Oil pressure at master cylinder outlet port is low c. Clogged, crushed tube between relay valve and brake
1
(outlet port hose disconnected) Repair or replace
chamber
d. Defective brake chamber seal Replace
e. Defective operation of master cylinder, worn packing Repair or replace
a. Defective brake chamber seal Replace
2 Air pressure at brake chamber inlet port is normal
b. Defective operation of master cylinder, worn packing Repair or replace
3 Air pressure at brake chamber inlet port is low b. Defective relay valve Repair or replace
c. Clogged, crushed tube between relay valve and brake
Repair or replace
chamber
4 Air leakage from brake chamber a. Defective brake chamber seal Replace
Items 1 - 4 are normal, but slack adjuster outlet
5 a. Defective slack adjuster operation Repair or replace
pressure is low
Items 1 - 5 are normal, but but brake piston pressure
6 a. Worn piston seal ring Replace
is low
7 Excessive contamination of cooling oil a. Excessive brake disc wear Replace
a. Worn piston seal ring Replace
8 Oil level in final drive case rises b. Defective floating seal between brake cooling chamber
Replace
and final drive
a. Defective floating seal between brake cooling chamber
9 In item 7, brake piston oil pressure is normal Replace
and final drive
Items 1 - 5 are normal, but brake is ineffective or
10 a. Excessive brake disc wear Replace
braking effect is poor.

H-12 Steering wheel is difficult to turn
• Is the oil level in the hydraulic tank correct?
• Is there any external oil leakage between the pump and steering valve?
• Is the steering wheel play correct?
• Operating effort of steering wheel
• Time required to turn the steering wheel from lock to lock
• Relief pressure of steering circuit

Circuit pressure is too high at engine low idle or
1 a. Defective check valve in demand valve Repair or replace
pressure rises to relief pressure
a. Crushed suction tube Repair
b. Air sucked in at suction end Repair
c. Clogged strainer Clean
2 Relief pressure in steering circuit is too low d. Defective steering pump Replace
e. Defective hoist pump Replace
f. Drop in demand valve relief valve pressure or defective Adjust, repair, or
seal replace
g. Defective steering cylinder Replace
3 Hoist force is also low
d. Defective steering pump Replace
seal replace
Item 3 is normal and sound of oil blowing through a. Drop in demand valve relief valve pressure or defective Adjust, repair, or
4
relief valve is heard seal replace
Relief pressure is low at end of cylinder stroke (items
5 a. Defective steering cylinder Replace
1 - 4 are normal)
6 Abnormal noise comes from between pump and filter a. Air sucked in at suction end Repair
When steering wheel is turned to right (left) oil flows a. Defective steering cylinder Replace
7 out continuously when hose on opposite side is
removed b. Defective steering valve Repair or replace

8 Condition is normal at engine low idle
b. Clogged strainer Clean
a. Defective steering pump Replace
9 Pump volume is too low
b. Defective hoist pump Replace
a. Defective demand valve spool operation or stuck spool Repair
10 Item 3 is normal, but speed is slow
b. Defective steering valve Repair or replace
11 Excessive play in steering wheel a. Defective steering valve Repair or replace

H-13 Steering wheel is inoperative
• Is the hydraulic tank oil level correct?
• Is there any external oil leakage between the pump and steering valve?
• Is the steering wheel play correct?
• Relief pressure

1 Hoist cylinder also does not work d. Defective steering pump Replace
seal replace
g. Improper operation of demand valve spool or stuck
Repair
spool
No oil comes out when pressure pickup port plug and
2 a. Defective pump drive (PTO) Repair
engine is cranked
Circuit pressure is too high at engine low idle, or
3 a. Improper operation of demand valve check valve Repair
pressure rises to relief pressure (item 2 normal)
a. Improper operation of demand valve spool or stuck
Repair
spool
4 Hoist is normal b. Improper operation of demand valve check valve Repair
c. Defective steering cylinder Replace
d. Defective steering valve Replace
a. Drop in demand valve relief valve pressure or defective Adjust, repair, or
Relief pressure is low at end of cylinder stroke (item 4 seal replace
5
normal) b. Defective steering cylinder Replace
c. Defective steering valve Replace
Item 5 is normal and sound of oil blowing through a. Drop in demand valve relief valve pressure or defective Adjust, repair, or
6
relief valve is heard seal replace
7 Abnormal noise comes from between pump and filter a. Air sucked in at suction end Repair
8 Steering wheel operates when engine is at low idle
When steering wheel is turned to right (left) and hose
9 on opposite side is removed, rod does not move, but a. Defective steering cylinder Replace
oil flows out.
a. Defective steering pump Replace
10 Pump volume is too low
b. Defective hoist pump Replace
11 Excessive play in steering wheel a. Defective steering valve Replace
H-14 Steering wheel vibrates
CAUSE REMEDY
Air in hydraulic oil Clean
Air leakage inside steering cylinder Repair or replace

H-15 Hoist cylinder lacks lifting force (lifting speed)
• Is the hydraulic tank oil level correct?
• Is the control lever actuation normal?
• Is the control cable corroded?
• When the cable is disconnected at the hoist valve end, does the control lever move normally?
• Is there any external oil leakage between the pump and cylinder?
• Relief pressure
• Body lifting speed

a. Air sucked in at suction side of pump Repair
c. Crushed suction tube Repair
1 Steering wheel is also difficult to turn
d. Drop in performance of hydraulic pump Replace
e. Drop in performance of steering pump Replace
f. Drop in demand valve relief valve pressure or defective Adjust, clean or
seal replace
a. Improper operation of demand valve spool or stuck
Repair
spool
b. Improper operation of demand valve check valve Repair
c. Drop in hoist valve relief valve pressure or defective seal Adjust or replace
2 Steering wheel is normal
d. Drop in hoist valve safety valve pressure or defective
Adjust or replace
seal
e. Defective hoist valve suction valve seal Clean or adjust
f. Improper hoist valve check valve operation Repair
g. Defective hoist cylinder Replace
Item 1 is defective and hoist circuit relief pressure is c. Crushed suction tube Repair
3
low d. Drop in performance of hydraulic pump Replace
e. Drop in performance of steering pump Replace
f. Drop in demand valve relief valve pressure or defective Adjust, clean or
seal replace
Item 3 is abnormal and the sound of oil blowing a. Drop in demand valve relief valve pressure or defective Adjust, clean or
4
through relief valve is heard seal replace
Hoist circuit pressure is too high at engine high idle a. Improper operation of demand valve check valve Repair
5
(items 1 - 4 are normal) b. Improper hoist valve check valve operation Repair
a. Drop in hoist valve relief valve pressure or defective seal Adjust or replace
6 Only hoist circuit relief pressure is low
b. Defective hoist cylinder Replace

Item 6 is abnormal and the sound of oil blowing
7 a. Drop in hoist valve relief valve pressure or defective seal Adjust or replace
through relief valve is heard
8 Dump body rises irregularly a. Crushed suction hose Repair
a. Drop in performance of hydraulic pump Replace
9 Pump volume is low
b. Drop in performance of steering pump Replace
a. Drop in hoist valve safety valve pressure or defective
Adjust or replace
seal
10 Excessive hoist cylinder hydraulic drift
b. Defective hoist valve suction valve seal Clean or adjust
c. Defective hoist cylinder Replace
a. Drop in hoist valve safety valve pressure or defective
External leakage of oil from valve (tank cover Adjust or replace
11 seal
removed)
b. Defective hoist valve suction valve seal Clean or adjust
Items 1 - 9 are normal, but dump body lifting speed is a. Improper operation of demand valve spool or stuck
12 Repair
slow spool
b. Drop in performance of hydraulic pump Replace

H-16 Hoist cylinders do not operate
• Did the problem suddenly happen?
YES = Seizure, damage to equipment
• Had drop in lifting speed or other symptoms appeared before?
YES = Worn parts, deteriorated spring, etc.

• Is the oil level in the hydraulic tank correct?
• Is the operation of the control levers normal?
• When the cable is disconnected at the hoist valve end, does the control lever move normally?
• Relief pressure

No oil comes out of pressure pickup port when plug is
1 a. Pump does not turn (defective PTO) Repair
removed and engine is cranked
a. Pump does not turn (defective PTO) Repair
b. Crushed pump suction tube Repair
2 Steering also does not work
d. Defective hydraulic pump Replace
e. Defective steering pump Replace
seal replace
a. Defective demand valve spool operation or stuck spool Repair
b. Defective demand valve check valve Repair
Adjust, repair, or
c. Drop in hoist valve relief pressure or defective seal
replace
3 Steering is normal, only hoist is inoperative
d. Drop in hoist valve safety valve pressure or defective Adjust, repair, or
seal replace
e. Defective hoist valve suction valve seal Repair or replace
f. Defective hoist valve check valve Repair or replace
g. Defective hoist cylinder Replace
a. Defective demand valve check valve Repair
Adjust, repair, or
b. Drop in hoist valve relief pressure or defective seal
replace
4 In item 2, hoist circuit relief pressure is low c. Drop in hoist valve safety valve pressure or defective Adjust, repair, or
seal replace
d. Defective hoist valve suction valve seal Repair or replace
e. Defective hoist valve check valve Repair or replace
f. Defective hoist cylinder Replace
Item 4 is abnormal and the sound of oil blowing a. Drop in demand valve relief valve pressure or defective Adjust, repair, or
5
through relief valve is heard seal replace

Adjust, repair, or
a. Drop in hoist valve relief pressure or defective seal
replace
Only hoist circuit relief pressure is low at engine high b. Drop in hoist valve safety valve pressure or defective Adjust, repair, or
6
idle seal replace
c. Defective hoist valve suction valve seal Repair or replace
d. Defective hoist cylinder Replace
Item 4 is abnormal and the sound of oil blowing Adjust, repair, or
7 a. Drop in hoist valve relief pressure or defective seal
through relief valve is heard replace
Hoist circuit pressure is too high at engine low idle or a. Defective demand valve check valve Repair
8 pressure rises to relief pressure (items 1 - 5 are
normal) b. Defective hoist valve check valve Repair or replace
a. Crushed pump suction tube Repair

9 Works when engine is at low idle
a. Defective hydraulic pump Replace
10 Pump volume is low
b. Defective steering pump Replace
When hoist lever is moved to RAISE, and hose on
11 opposite side is removed, cylinder does not move, a. Defective hoist cylinder Replace
but oil comes out

H-17 Excessive dump body hydraulic drift
• When the control lever cable is disconnected at the valve end, does the hydraulic drift come within the
standard range?
YES = Cable is corroded or needs lubrication
• Hydraulic drift of cylinder

When engine is stopped and control lever is moved a. Defective hoist cylinder piston ring Replace
1
to RAISE, hydraulic drift becomes excessive b. Defective hoist valve Repair or replace
Oil continues to
2 When engine is stopped, with a. Defective hoist cylinder piston ring Replace
flow out
body fully raised and the head
piping is removed Oil does not b. Defective suction valve seal Repair or replace
3
continue to flow out c. Defective valve spool seal Replace

H-18 Air pressure does not increase (low-pressure buzzer does not turn
off. Air pressure does not increase to green range.)

• Is the air gauge normal?
• Is there any air leakage from air piping?

When compressor outlet port is removed, no air a. Defective compressor Replace
1
comes out b. Defective unloader valve Repair or replace
There is no change even after unloader valve is
2 a. Defective compressor Replace
disassembled and cleaned
Pressure rises when hose between governor and
3 a. Defective governor Adjust or replace
unloader valve is removed
4 Compressor is overheating a. Crushed tube between compressor and air tank Repair or replace
Even when pressure gauge indicator rises to green
5 range, buzzer does not stop (pressure gauge is a. Defective low-pressure switch Replace
normal)
Air pressure does not rise, but air blows out from
6 a. Defective safety valve Replace
safety valve

NOTES

SECTION F
TRANSMISSION
INDEX
TORQUE CONVERTER OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-2

Main Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-7
Torque Converter Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-7
Lock Up Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-9
Hydraulic Pressure of the Torque Converter . . . . . . . . . . . . . . . . . . . . . . . F2-12
Torque Converter Stall Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F2-14
TRANSMISSION OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F2-15
ECMV (Electronic Control Modulation Valve) . . . . . . . . . . . . . . . . . . . . . . F2-19
Lubrication Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F2-29
TRANSMISSION
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F2-30
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F2-32
TRANSMISSION FILTER
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F2-34
TRANSMISSION OIL COOLER

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-1
TRANSMISSION OIL STRAINER

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-1
TORQUE CONVERTER CONTROL VALVE
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-2
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-2
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-2
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-3
DRIVELINES & U-JOINTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-1
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-1
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-1
AUTOMATIC SHIFT CONTROL SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . F6-1

GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-1
TRANSMISSION SHIFT CONTROLLER . . . . . . . . . . . . . . . . . . . . . . . . . F6-1
Power Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-1
Braking Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-1
Lock-Up and Engine Overspeed . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-1
Transmission Speeds Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-1
Self Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-2
F01010 3/99 Index F1-1

RANGE SELECTOR POSITIONS AND AUTOMATIC GEAR SHIFTING RANGES . . . F6-4
Transmission Operation Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-4
AUTOMATIC GEAR SHIFTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-5
Automatic Shifting Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-5
Safety Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-7
TRANSMISSION RANGE SELECTOR . . . . . . . . . . . . . . . . . . . . . . . . . . F6-8
SENSORS, SWITCHES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F6-9
TRANSMISSION TROUBLESHOOTING PROCEDURES . . . . . . . . . . . . . . . F6-12
F1-2 Index F01010 3/99

TRANSMISSION
The 330M Truck utilizes a remote mounted, 7 speed Operation of the transmission is controlled electroni-
transmission. The TORQFLOW transmission (8, Fig- cally through inputs from the operator (range selector
ure 2-1) consists of a water-cooled, 3-element, single- position, accelerator, etc.) and various sensors and
stage, two phase torque converter (7) and a switches monitoring speeds and operating conditions.
planetary-gear, multiple-disc clutch transmission
The transmission oil supply is filtered through a wash-
which is hydraulically actuated and pressure lubricated
able strainer located in the transmission sump and by
for optimum heat dissipation.
external, replaceable elements located at the front of
A rubber dampened drive line adapter (2), coupling the the hydraulic tank. The transmission filter element
engine to the transmission and torque converter, re- should be replaced at 500 hour intervals, or sooner, if
duces harmful engine shock and vibration to the trans- the warning light indicates high restriction. Refer to
mission. A lockup system, consisting of a wet, Section "P", Lubrication And Service. The transmis-
double-disc clutch, can be actuated in all forward gears sion oil should be drained, and the strainer removed
for higher fuel savings. and cleaned, every 1000 hours of operation.
FIGURE 2-1. POWER TRAIN

1. Engine 8. Transmission
2. Driveline Adapter 9. Rear Drive Shaft
3. Front Drive Shaft 10. Parking Brake
4. Steering and Hoist Pump 11. Differential Gear
5. Brake Cooling Pump 12. Drive Shaft
6. Torque Converter Transmission Pump 13. Brakes
7. Torque Converter 14. Planetary Gears
F02016 11/98 Transmission F2-1

TORQUE CONVERTER
The torque converter is a 3-element, single-stage, two
phase torque converter with lockup clutch. A water-to-
oil type oil cooler is utilized to dissipate heat from the
oil supply.
Stall ratio: . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4:1.
FIGURE 2-3. TORQUE CONVERTER HOUSING

1. Torque Converter A. From Pump
Outlet Temperature B. To Transmission
Test Port Shift Valve
FIGURE 2-2. TORQUE CONVERTER DRIVE 2. Torque Converter C. To Transmission
1. Gear (63 Teeth) 4. Steering and Hoist Outlet Pressure Test Lubrication
2. Gear (53 Teeth) Pump Drive Port
3. Brake Cooling 5. Torque Converter and 3. Solenoid Valve
Pump Drive Transmission Charge 4. Torque Converter Valve
Pump Drive
F2-2 Transmission F02016 11/98

TORQUE CONVERTER
FIGURE 2-4. TORQUE CONVERTER
1. Front Housing 7. Drive Case 13. Drain Plug

2. Lockup Clutch Housing 8. Stator 14. One-way Clutch
3. Lockup Clutch Piston 9. Pump 15. Gear (56 Teeth)
4. Disc 10. Rear Housing 16. Input Shaft
5. Plate 11. Stator Shaft 17. Coupling
6. Turbine 12. Retainer

TORQUE CONVERTER VALVE
FIGURE 2-5. TORQUE CONVERTER VALVE FIGURE 2-6. TORQUE CONVERTER VALVE
(External View) (Internal components)
A: Lockup Pressure Port 1. Piston

B: Main Pressure Port 2. Piston
C: Torque Converter Inlet Pressure Port 3. Spool (Lockup Valve)
4. Spool (Main Relief Valve)
5. Piston
6. Spring
7. Body
8. Spool (Torque Converter Relief Valve)
9. Piston
10. Spring
11. Piston
12. Spring

TORQUE CONVERTER AND
TRANSMISSION HYDRAULIC PIPING
FIGURE 2-7. TORQUE CONVERTER AND TRANSMISSION PIPING
1. Torque Converter Valve 3. Breather 5. Hydraulic Pump (SAR4-160)

2. Transmission 4. Transmission Oil Filter 6. Torque Converter Oil Cooler

HYDRAULIC PUMP
Torque converter and transmission
Volume: . . . . . . . . . . . . . . 162.2 cc/rev (0.042 gpr)

Maximum Pressure: . . . . . 210 kg/cm2 (3000 psi)
Maximum Speed: . . . . . . . . . . . . . . . . . . . 2200 rpm
FIGURE 2-8. HYDRAULIC PUMP
1. Drive Gear 5. Gear Case

2. Bracket 6. Cover
3. Oil Seal 7. Driven Gear
4. Side Plate

MAIN RELIEF VALVE
Function
The main relief valve maintains the main hydraulic
pressure of the transmission valve, lockup valve, and
pilot pressure.
Operation
The oil from the hydraulic pump enters port (A, Figure
2-9), then passes through orifice (2) and goes to port
C.
When the hydraulic pressure in the circuit rises, the
pressure at port C also rises and pushes main relief
spool (1) to the left, in the direction of the arrow. The
oil at port A passes through port B and flows to the
torque converter circuit.
Actuating pressure:
Engine @ high idle RPM: . . . . . . . . 39 ± 2 kg/cm2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (555 ±29 psi)
FIGURE 2-9. MAIN RELIEF VALVE

1. Main Relief Spool 2. Orifice
TORQUE CONVERTER RELIEF VALVE
Function
This valve acts to protect the torque converter circuit
from abnormally high pressure.
Operation
The oil from the main relief valve enters port B (Figure
2-10) and then passes through orifice (2) and goes to
port A. When the pressure in the circuit rises, the
pressure at port A also rises, and moves torque con-
verter relief spool (1) to the right in the direction of the
arrow. The oil at port B flows to port C and goes to the
transmission lubrication circuit.
Actuating pressure:
FIGURE 2-10. TORQUE CONVERTER RELIEF
Engine @ high idle RPM . . . . . . . . . . 8 ±1 kg/cm2 VALVE
1. Relief Spool 2. Orifice
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (113 ±15 psi)

LOCKUP SOLENOID VALVE
FIGURE 2-11. LOCKUP SOLENOID VALVE
1. Cover 7. Spring A. From torque converter valve

2. Coil 8. Valve seat B. To torque converter valve
3. Spring 9. Cap C. To torque converter valve
4. Plunger 10. Cable
5. Valve seat holder 11. Connector
6. Valve seat

LOCKUP VALVE
Function
The lockup valve sets the specified pressure for the

lockup clutch hydraulic pressure, and also switches
the lockup clutch.
It has a modulation valve, which engages the lockup
clutch smoothly, and reduces the shock when shifting
gears. Furthermore, it prevents the generation of peak
torque in the power train. As a result, the durability of
the power train is greatly increased.
The chart in Figure 2-12 illustrates the time delay
incorporated in the electronic control system to delay
lockup as the hydraulic pressure increases.
FIGURE 2-12. LOCKUP VALVE DELAY
Operation
Driving in torque converter range with lockup off (Refer

to Figure 2-13).
When the machine is driving in the torque converter
range, solenoid valve (1) is switched OFF by an elec-
trical signal, and valve (2) is pushed to the right in the
direction of the arrow by the tension of spring (4), so
port B and port P of solenoid valve (1) are opened. The
oil from the pump enters port A of lockup valve (3),
passes through port B and port P of solenoid valve (1),
and goes to port D. Piston (6) is pushed to the left in
the direction of the arrow because of the hydraulic
pressure applied to port D. This force pushes lockup
valve (3), compresses spring (5), and closes port A to
port E.
The oil at port E and port H is drained, and the lockup FIGURE 2-13. LOCKUP VALVE OPERATION
clutch is disengaged. 1. Solenoid Valve 4. Spring
2. Valve 5. Spring
3. Lockup Valve 6. Piston

Driving in direct range with lockup on.
(Refer to Figure 2-14 through 2-17):
1. When the machine travels in the direct range

(lockup), solenoid valve (1) is switched ON by the
electrical signal, and valve (2) is pushed to the left
in the direction of the arrow, so port B is closed,
and port P and port C are opened.
As a result, the oil at port D flows from port P of

solenoid valve (1), passes through port C and is
drained. Lockup valve (3) and piston (6) are
pushed to the right by spring (5), and port E are
opened.
FIGURE 2-14. LOCKUP VALVE OPERATION (1)
2. When port A and port E are opened, the oil from

the pump is sent to the lockup clutch. In addition,
the oil at port E flows to port F and applies back
pressure to load piston (7).
3. As the hydraulic pressure of the lockup clutch

rises, the pressure of the oil passing through
orifice A and entering port G also rises, and
pushes piston (8).
Because of the reaction force, lockup valve (3)

compresses spring (5) and pushes it to the left in
the direction of the arrow to throttle port A and port
E.

4. The oil from port E to port F applies pressure to
load piston (7), and pushes the piston to the right
in the direction of the arrow to compress spring
(5).
Compressed spring (5) pushes lockup valve (3)

to the right in the direction of the arrow, and opens
port A and port E. When this happens, the in-
crease in hydraulic pressure to the lockup clutch
again increases.
5. By repeating the actions in Steps 3. and 4., the

load on spring (5) is increased, and the hydraulic
pressure gradually rises.
Finally, when load piston (7) contacts stopper (9),
the rise in hydraulic pressure stops. The pressure
at this point is the set pressure of the lockup valve.
Set pressure: . . . . . . . . . . . . 16kg/cm2 (230 psi)

TESTING HYDRAULIC PRESSURE OF
TORQUE CONVERTER VALVE
Testing main relief pressure

1. Raise the dump body and lock it with safety pin.
The oil is at high temperature. Use caution to

prevent burns.
Always remove and install the plugs and hydraulic
pressure gauge with the engine stopped.
2. Raise the transmission oil temperature to 60-80°

C (140-176° F) and shut down engine. FIGURE 2-19. TORQUE CONVERTER PRESSURE
2
3. Remove plug (1, Figure 2-20). Install a 60 kg/cm
(850 psi) gauge (A, Figure 2-19) in the port.
4. Start the engine, place the gearshift lever at N.
At high idle, the hydraulic pressure should be:
39 ± 2 kg/cm2 (555 ±29 psi)
5. Shut down engine, remove gauge and reinstall
plug (1).
Testing hydraulic pressure at torque converter

inlet port (relief)
1. Perform the main relief pressure test (above) prior
to the next step.
2. With the engine shut down, remove plug (2, Figure
2-20). Install a 25 kg/cm2 (350 psi) gauge in the
port.
3. Start the engine. At high idle, the hydraulic pres-
sure should be:
8 ± 1 kg/cm2 (113 ±15 psi).
4. Shut down engine, remove gauge and install plug.
Testing hydraulic pressure at torque converter

outlet port (regulator)
1. Raise the transmission oil temperature to 60°-80°
C (140°-176° F). Shut down the engine.
2. Remove plug (3, Figure 2-20). Install a 25 kg/cm2
(350 psi) gauge in the port. FIGURE 2-20. TORQUE CONVERTER TEST
PORTS
3. Start the engine. At high idle, the hydraulic pres- 1. Main Relief Pressure Port
sure should be: 2. Torque Converter Inlet Pressure Port
4 ± 1 kg/cm2 (57 ±15 psi) 3. Torque Converter Outlet Pressure Port
4. Shut down engine, remove gauge and install plug. 4. Torque Converter Lockup Pressure Port

Testing torque converter lockup pressure
Note: Prior to checking lockup pressure, test and verify 7. Press the 4th range button again to return to
main relief pressure is normal. neutral (N). Turn shift checker power switch Off.
8. Shut down the engine and remove the gauge
1. Shut down engine and be certain ignition is Off. installed in step 3 and replace port plug.
2. Install the shift checker (Refer to Figure 2-21): 9. If no further tests are to be performed, the shift
a. Disconnect the chassis harness (6, Figure checker may be removed.
2-21) from the transmission control box (4). a. Disconnect harness connectors (5, Figure 2-
b. Connect shift checker harness (3) (white con- 21) from chassis harness (6) and remove shift
nectors) to the truck chassis harness connec- checker.
tors (SC1, SC2, SC3 & SC4) removed in step b. Reconnect chassis harness connectors to
a. transmission control box (4).
c. Be certain shift checker power switch is Off.
Connect harness (3) black connector to shift
checker. TORQUE CONVERTER STALL SPEED
3. Remove plug (4, Figure 2-20). Install a 60 kg/cm 2 CHECK
(850 psi) gauge in the port.
Preparing For Stall Speed Check
4. Start the engine, allow air pressure to build to
normal operating range and be certain the park- Prior to running a stall test, insure that all systems such
ing brake is applied. as exhaust piping, air intake piping, fuel controls, and
engine warning systems are all working properly and
5. Turn the shift checker power switch On. within specifications. Insufficient fuel or restricted pip-
a. Press the 4th range shift button. ing can affect stall speed.
b. With the engine at high idle, press the lockup The automatic transmission develops high torque in
button to engage the lockup clutch. The hy- low gear ranges. Therefore, preparations must be
draulic pressure should be: made to shift the transmission to the highest gear
16 ± 0.5 kg/cm2 (230 ± 10 psi). range available to lower output torque.
6. Press the lockup button again to turn lockup Off. This allows the truck service brakes to hold the truck
motionless during the stall check procedure.
NOTE: If shift checker 799-607-2000 is to be used on

trucks serial number A10190 or higher, harness
connector 799-607-2120 must be used. Or, use shift
checker 799-607-3000 and connect directly to trucks
with serial numbers A10190 & higher.
FIGURE 2-21. SHIFT CHECKER INSTALLATION

1. Shift Checker (Part No. 799-607-2000 or 799-607-3000) 4. Transmission Control Box
2. Harness connector (to Shift Checker, see NOTE above) 5. Harness connectors (to Chassis Harness)
3. Harness Assembly 6. Truck chassis Harness (Transmission Control Box)

Personnel and equipment safety is of prime impor-
tance when performing a stall check!
The operator must be seated in position in the cab
at all times during the stall checks.
Personnel other than those performing the checks
must be clear.
The vehicle brakes must be capable of holding the
FIGURE 2-22. CHECKING ENGINE SPEED
machine at full power during the stall checks.
Be certain truck is securely blocked prior to testing
7. Apply the parking brake, and depress the brake
torque converter stall speed.
pedal fully:
Wheel chocks should always be used.
a. If Shift Checker is installed, then turn the shift
checker power switch "On". Use transmission
or the shift checker to shift transmission to
highest range available (F3). See figure 2-21.
If available, the stall check should be done using a Shift b. If Shift Checker is NOT installed, move trans-
Checker, as this will allow the transmission to be mission shift lever to "D" (Drive).
shifted to F-3 gear range, thus reducing output torque.
8. Keeping all brakes applied, operate the engine at
1. Stop the machine on flat ground and block the full throttle and stall the torque converter. When
wheels. Shut down engine and be certain the oil temperature reaches 100°C (212°F), return the
keyswitch is "Off". transmission to "N" and keep the engine at full
throttle.
2. Install the shift checker (Refer to Figure 2-21):
Repeat this procedure until the oil temperatures
a. Disconnect the chassis harness (6, Figure
in both the torque converter and the transmission
2-21) from the transmission control box (4).
are the same.
b. Connect shift checker harness (3) to the truck
chassis harness connectors removed in step a. 9. With the oil temperature at approximately 80° C
(176° F), measure the stall speed as follows:
c. Be certain shift checker power switch is Off.
Connect harness (3) connector to shift a. Apply the parking brake and depress the foot
checker. service brake fully.
b. Use shift checker to set the transmission to
3. Use an accurate strobe tach or similar device of
highest range available (or move transmission
known accuracy to verify engine RPM reading on
shift lever to "D") and measure engine speed
truck instrument panel.
with the engine at full throttle.
4. Move transmission shift lever to Neutral and start c. Repeat 2 or 3 times.
engine. Be sure that the "Power Mode" switch on
the center console is "Off" (out). Raise engine Converter Stall speed: . . 2,090 ±100 RPM
water temperature and transmission oil tempera- NOTE: The stall speed may vary according to the
ture to the normal operating range. following conditions, therefore always measure the
stall speed at the time of delivery.
5. Measure the engine high idle and low idle RPM.
• Variations according to engine serial number.
If either speed is not according to truck specifica-
tions, refer to the appropriate engine manual and • Variations in engine horsepower due to atmos-
adjust high/low idle speed. pheric pressure and temperature.
6. Raise the temperature of the hydraulic oil and • Variations in parasitic losses from accessories.
transmission oil.
• Variations due to torque converter features.
Oil temperature when measuring:
Hydraulic oil: . . . 45°-55° C (113-131° F) • Variations due to method of measuring the stall.
Transmission: . . . 60°-80° C (140°-176° F) 10. Return all hook-ups to normal operating condition.

TRANSMISSION
FIGURE 2-23. TRANSMISSION

1. Speed Sensor Mount Port (input shaft rpm) A: Low Clutch Port
2. Speed Sensor Mount Port (intermediate shaft rpm) B: 1st Clutch Port
3. Input Shaft C: 2nd Clutch Port
4. Transmission Lubrication Relief Valve D: R Clutch Port
5. Speedometer Cable Pickup Port E: 3rd Clutch Port
6. Output Yoke F: 4th Clutch Port
7. Drain Valve G: High Clutch Port
8. Speed Sensor Mount Port (output shaft rpm) H: From Oil Cooler
9. Strainer I: Lube Pressure Test Port
J: From Torque Converter (main circuit)
K: From Torque Converter (lubrication circuit)
L: To Pump (suction)
M: From Torque Converter (sump circuit)

TRANSMISSION SHIFT VALVES
FIGURE 2-24. TRANSMISSION SHIFT VALVES

1. ECMV (for high clutch)
2. ECMV (for low clutch)
3. ECMV (for 4th clutch)
4. ECMV (for 3rd clutch) SPEED ECMV
5. ECMV (for reverse clutch) RANGE R 1st 2nd 3rd 4th L H
6. ECMV (for 2nd clutch) F1
7. ECMV (for 1st clutch)
8. Valve Oil Screen F2
9. Seat F3
10. Breather F4
11. Cover
F5
A. High Clutch Pressure Tap Port F6
B. Low Clutch Pressure Tap Port F7
C. 4th Clutch Pressure Tap Port N
D. 3rd Clutch Pressure Tap Port
E. Reverse Pressure Tap Port R1
F. 2nd Clutch Pressure Tap Port
ECMV CLUTCH OPERATION TABLE
G.1st Clutch Pressure Tap Port

TORQUE CONVERTER AND TRANSMISSION HYDRAULIC CIRCUIT DIAGRAM
16 ±0.5 kg/cm2
(230 ±10 psi) 16.5 ±1.5 kg/cm2
(235 ±20 psi)
39 ±2 kg/cm2 16.5 ±1.5 kg/cm2

(555 ±29 psi) (235 ±20 psi)
8 ±1 kg/cm2 16.5 ±1.5 kg/cm2

(115 ±15 psi) (235 ±20 psi)
By-Pass Warning Light

2.5 kg/cm2 (35 psi)
Actual Oil By-Pass
3.5 kg/cm2 (50 psi)
Crack Open 20.5 ±1.5 kg/cm2
Pressure (290 ±20 psi)
2.7 kg/cm2
(38 psi)
Normal Operating
Pressure
1.25 ±.5 kg/cm2
(18 ±6 psi) 30.5 ±1.5 kg/cm2
(435 ±20 psi)
336 l/mn 31.5 ±1.5 kg/cm2

(90 gpm) @ 2100 RPM (450 ±20 psi)
31.5 ±1.5 kg/cm2

(450 ±20 psi)
FIGURE 2-25. HYDRAULIC CIRCUIT DIAGRAM

1. Strainer 8. ECMV for high clutch 14. 4th Clutch 20. Lockup Solenoid Valve
2. Hydraulic Pump 9. ECMV for 4th clutch 15. 3rd Clutch 21. Lockup Clutch
3. Transmission Oil Filter 10. ECMV for R clutch 16. R Clutch 22. Torque Converter Relief Valve
4. Oil Screen 11. ECMV for 1st clutch 17. 2nd Clutch 23. Main Relief Valve
5. ECMV for low clutch 12. High clutch 18. 1st Clutch 24. Oil Cooler
6. ECMV for 3rd clutch 13. Low clutch 19. Lockup Valve 25. Lubrication Relief Valve
7. ECMV for 2nd clutch 26. Transmission Lubrication

ECMV (ELECTRONIC CONTROL MODULATION VALVE)
FIGURE 2-26. ECMV (ELECTRONIC CONTROL MODULATION VALVE)

1. Connector 6. Proportional Solenoid A: To clutch
2. Spring 7. Pressure Control Valve Spool B: Drain
3. Flow Sensor Valve Spool 8. Load Piston C: From Pump
4. Spring 9. Spring a: CLutch Pressure Measurement Port
5. Fill Switch

ECMV (Electronic Control Modulation
Valve)
The ECMV (Electronic Control Modulation Valve) con-
sists of two valves: a pressure control valve and a flow
sensor valve.
Pressure control valve

The pressure valve contains a proportional solenoid
which takes the current sent from the transmission
controller and the pressure control valve converts this
current into hydraulic pressure. (Refer to Figure 2-27.)
Flow sensor valve

This valve is actuated by a trigger from the pressure
control valve, and has the following functions:
1. The valve is opened until the clutch is filled with
oil, thereby reducing the time (filling time) taken
for oil to fill the clutch.
2. When the clutch becomes full of oil, the valve
closes, and sends a signal (full signal) to the
controller to inform that filling is completed.
3. While there is hydraulic pressure applied to the FIGURE 2-27.
clutch, it outputs a signal (full signal) to the con- A range: Before Gear Shifting (drained)
troller to inform whether there is hydraulic pres- B range: Filling Starts (trigger issued)
sure or not. C range: Filling Completed
D range: Regulation
ECMV and proportional solenoid E range: Filling
Each ECMV is equipped with one proportional sole-
noid.
The propulsion force shown in the diagram in Figure
2-28 is generated according to the command current
from the controller.
The propulsion force generated by the proportional
solenoid acts on the pressure control valve spool and
this generates the hydraulic pressure shown in the
diagram on the right. In this way, by controlling the
command current, the propulsion force is changed and
this acts on the pressure control valve to control the oil
flow and hydraulic pressure.
ECMV and fill switch

Each ECMV is equipped with one fill switch. When the
clutch is completely filled, the flow sensor valve acts
to switch the fill switch on. As a result of this signal, the
oil pressure starts to build up.
FIGURE 2-28.

Action of ECMV
The ECMV is controlled by the command current from
the transmission controller to the proportional sole-
noid, and the output signal of the fill switch. The
relationship between the ECMV proportional solenoid
command current and clutch input pressure and the
output signal of the fill switch is as shown in the
diagram in Figure 2-29.
• A range: Before gear shifting (drained)
• B range: Filling starts (trigger issued)
• C range: Filling completed
• D range: Regulation
• E range: Filling
FIGURE 2-29.
Before shifting gear (drained) (A range of

graph)
1. (Refer to Figure 2-30): When no current is being
sent to proportional solenoid (6), the reaction
force for spring (9) of the pressure control valve
pushes pressure control valve spool (7). As a
result, proportional solenoid (6) is pushed pack,
so pressure control valve spool (7) connects the
oil at clutch port C to drain port E and drains the
oil.
In this condition, there is no hydraulic force acting
on spool (3) of the flow sensor valve, so the
reaction force of spring (4) for the fill switch moves
flow sensor valve spool (3) away from fill switch
(5), and stops it in a position where it is in balance
with return spring (2) of the flow sensor valve.
FIGURE 2-30.

Starting to fill (trigger command input to pres-
sure control valve) (B range of graph)
1. (Refer to Figure 2-31): When there is no oil inside
the clutch and the trigger current is sent (maxi-
mum current is applied) to proportional solenoid
(6), the proportional solenoid moves the full
stroke and pressure control valve spool (7) moves
to the left. As a result of this, pump port A and
pressure control valve output port B are opened,
and oil passes through orifice “a” of flow sensor
valve spool (3) and starts to fill the clutch.
FIGURE 2-31.
2. (Refer to Figure 2-32): When this happens, a

pressure difference is created between the up-
stream and downstream sides of orifice “a” of flow
sensor valve spool (3). Because of this difference
in pressure, flow sensor valve spool (3) moves to
the left and compresses sensor valve return
spring (2).
As a result, flow sensor valve spool (3) opens
pump port D, and oil flows from here through
orifice “a” and goes to the clutch port.
FIGURE 2-32.
Filling completed (pressure control set to in-
itial pressure) (C range of graph)
1. (Refer to Figure 2-33): When pump port D of the
flow sensor valve opens, and the oil flows out from
here, a difference in pressure is created between
the upstream and downstream sides of orifice “a”
of the flow sensor valve spool (3). This continues
to push flow sensor valve spool (3) to the left.
When this happens, and the current of propor-
tional solenoid (6) is lowered momentarily to the
initial pressure level, almost the complete pump
pressure comes to bear on load piston (8). As a
result, pressure control valve spool (7) is pushed
back to the right, and a small amount of oil leaks
from pressure control valve outlet port B to drain
port E. However, only a small amount of oil leaks,
so almost all of the oil from the pump flows to the FIGURE 2-33.
clutch, and flow sensor valve spool (3) continues
to be pushed to the left.

2. (Refer to Figure 2-34): When the clutch is filled
with oil, the flow of oil from pump port D to clutch
port C stops. The size of areas receiving pressure
on the left and right sides of flow sensor valve
spool (3) is different (the area on the left side is
larger), so when the pressure on both sides be-
comes the same, the spool is moved by hydraulic
force to the right. When this happens, pump port
D and clutch port C are closed. Because of this
difference in area on the left and right sides, and
the force of return spring (2) of the pressure
control valve, flow sensor valve (3) compresses
fill switch spring (4) and is pushed to the right. It
then contacts fill switch (5) and transmits the
clutch filling completed signal to the shift control-
ler. At this point, the current for the initial pressure
level is flowing to proportional solenoid (6), so the
hydraulic pressure is set to the initial pressure by
pressure control valve spool (7).
FIGURE 2-34.
Regulating (D range of graph)

1. (Refer to Figure 2-35): When current is sent to
proportional solenoid (6), the solenoid generates
a force proportional to the current. This propulsion
force of the solenoid, and the sum of the propul-
sion force produced by the hydraulic pressure at
the clutch port applied to load piston (8), and the
reaction force of pressure control valve spring (9)
are regulated so that they are in balance.
The difference in hydraulic pressure applied to
both sides of flow sensor valve spool (3) pushes
the spool to the right, and the fill signal continues
to be sent to the transmission controller.
FIGURE 2-35.

ECMV REPAIR PROCEDURE
1. Thoroughly wash and flush debris and dirt from
Transmission Control Valve mounted on top of
transmission.
2. Thoroughly wash and flush the area surrounding
the filter assembly (5, Figure 2-36) to prevent the
intrusion of sand, mud, dust, paint, etc.
3. Remove mounting nuts (2, Figure 2-36) and re-
move the ECMV protective cover (1). Flush area
under cover, taking care not to allow soil, sand,
dust, paint, etc. to enter the ECMV, valve seats,
etc.
Filter Cleaning Procedure

1. Remove the filter assembly protective cover (9,
Figure 2-36) and the restriction sensor connector
(4). Prior to removal of the complete filter assem-
bly (5) from the valve assembly, loosen the filter
case (8) from the filter head (6) by rotating
counter-clockwise, using the hex nut at the case
tip.
2. Remove the complete filter assembly (5).
NOTE: When the filter assembly is removed from the FIGURE 2-36. TRANSMISSION CONTROL VALVE
valve seat, some oil will flow out of the case on to the ASSEMBLY
transmission. Be prepared to minimize spillage.
1. Cover 7. Filter Element
3. Remove the case (3, Figure 2-37) from the filter 2. Mounting Nuts 8. Filter Case
head (1). 3. Harness 9. Cover
4. Remove filter element assembly (2) from head (1). 4. Sensor Connector 10. ECMV Assembly
Remove O-rings (4, 5). 5. Filter Assembly 11. ECMV Mounting Bolts
6. Filter Head 12. Valve Plate
5. Wash all foreign matter from the element with light
oil. Dry element using clean, dry, low pressure air.
If element is damaged or cannot be completely
cleaned, replace element.
6. Wash the head (1) and the case (3) with light oil.
7. Install O-rings (4, 5, Figure 2-37) into head (1) and
on case (3). Insert element (2) into case (3).
8. Install the case onto head. Tighten case hand
tight.
9. Install the assembled filter assembly onto the
valve seat. Tighten mounting capscrews to stand-
ard torque.
10. Tighten the filter case (3) to 6 to 8 kg.m (43 - 58
ft.lbs.) torque.
11. Install the restriction sensor connector (4, Figure FIGURE 2-37. FILTER ASSEMBLY
2-36) to the harness (3) and install the protective 1. Filter Head 4. O-Ring
cover (9). 2. Filter Element 5. O-Ring
3. Filter Case

ECMV Removal
1. Remove the paint along the boundary between
the fill switch assembly (16, Figure 2-38) and the
valve body (1) at each ECMV to be removed.
2. Disconnect the electrical connectors for the fill
switch assembly (16) and solenoid valve (9) from
the harness.
3. Remove the switch and solenoid connectors from
bracket (18).
Disassembly
1. Before disassembly, flush the ECMV and valve
seat (paint at corners of the mating surfaces must
be removed thoroughly).
NOTE: Do not allow the solenoid connectors, fill switch
connectors, or harness to be exposed directly to the
water, etc.
2. Remove the mounting bolts (8, Figure 2-39) from
the ECMV assembly (10), and separate the
ECMV assembly from valve plate (12). FIGURE 2-38. ECMV ASSEMBLY
3. Remove solenoid connector (2, Figure 2-39) and 1. Valve Body 13. Plug
fill switch connector (3) from bracket. Loosen 2. Plug 14. O-ring
bolts (17). Gently remove the flow sensor valve 3. Plug 15. Spring
fill switch (16) and bracket. Be careful not to let 4. Pressure Control Valve 16. Fill Switch
spring (15) fall out of place. 5. Piston 17. O-ring
6. Spring 18. Bracket
7. Shim 19. Bolt
8. O-ring 20. Washer
4. Remove cover plate (21, Figure 2-38). Remove 9. Solenoid Valve 21. Cover Plate
plug (13) by installing a capscrew in the tapped 10. Bolt 22. O-ring
hole for easier removal. Then, remove the flow 11. Flow Detection Valve 23. Bolt
detecting valve spring (12), valve spool (11), and 12. Spring
spring (15).
a. Examine valve body (1) and spool (11) as well
as spring (15) for the existence of plating film
pieces and other metallic particles. If found,
NOTE: Protect the valve plate (12, Figure 2-36) and
remove them.
the valve mating surfaces by applying masking tape,
etc. Prevent dirt/dust from entering the transmission
b. If foreign matter has lodged in the valves or the by covering all openings. Place all removed parts in
pistons, or if their functional movement is not storage, being careful not to scratch any part.
smooth, recondition them with an oil stone, etc.
5. Remove spring (6), shims (7), piston (5), and valve
(4) from the pressure control valve. Examine for
any trapped foreign matter, seized spool, or rough
movement. Be careful not to lose shims (7). Keep
shims in storage, after confirming their quantity.
6. Remove the proportional solenoid valve (9).

Reassembly
Inspect each part thoroughly and confirm that the part
is free from dirt/dust, scratches, etc. Wash all parts with
solvent. Lubricate spools and plungers with a small
amount of transmission oil during assembly. Be certain
to reassemble all spools and plungers into their original
valve body bores.
NOTE: When assembling the valve, make sure that
valve spools move smoothly in the bore.
This work should be performed in a “Clean Room”

or workstation free from dirt, dust, etc.
1. Set the pressure control valve spool (4, Figure

2-39) in the valve body (1). Be certain the valve
movement is smooth, by pushing the valve with
fingers on both ends.
2. Install the solenoid valve (9) together with O-ring
(8), using 4 bolts (10). Tighten bolt (10) to 1.35 ±
0.15 kgm (9 -11 ft.lbs.) torque.
3. Place the pressure control valve piston (5) inside
pressure control valve spool (4). Make sure that
piston movement is smooth, by pushing the valve
with fingers.
FIGURE 2-39. ECMV VALVE ASSEMBLY 4. Install shims (7) and spring (6) in the pressure
control valve. Install O-ring (22, Figure 2-38) in
the valve body.
1. Valve Body 10. Bolt
2. Solenoid Connector 11. Flow Sensor Valve
3. Fill Switch Connector 12. Spring • The standard number of shims is: 3 pcs.
4. Pressure Control Valve 13. Plug • Standard shim pack thickness: 0.6 mm
Spool 14. Pressure Test Port • Individual shim thickness: 0.2 mm
5. Load Piston 15. Spring
6. Spring 16. Fill Switch
7. Shims 17. Bolt NOTE 1: (Refer to Figure 2-39.) When parts (1), (6),
8. Mounting Bolt 18. Cover Plate (5), (4), and (9) are all being reused, the same number
9. Proportional Solenoid of shims removed during disassembly must be rein-
stalled. When any of these parts have been replaced,
the standard number of shims (3 ea.) should be in-
stalled. The exact quantity required is determined
when clutch pressure test is performed.
NOTE 2: When only the proportional solenoid valve (9)
is to be replaced, remove cover (18) and make sure
that spring (6) has been positively set in place. (There
is a possibility that the spring can get out of the valve
end when the proportional solenoid valve is removed.)

5. Install the flow sensor valve (11) in valve body (1). 11. Install all ECMV’s onto the valve seat, making sure
Make certain the valve movement is smooth, by that mounting surfaces are free from dirt/dust,
pushing the valve with fingers on both ends. scratches, etc. Secure all electrical connectors to
the harness.
6. Set the flow detecting valve spring (15, Figure
2-38) in place. Install O-ring (17) and position fill 12. Check clutch pressure for any ECMV that has
switch (16) and bracket (18) on valve body. Install been disassembled for repairs.
2 bolts (19) and tighten to 3.15 ± 0.35 kgm (20 -
25 ft.lbs.) torque.
7. Install spring (12) in the flow detecting valve.
Install new O-ring (14) on plug (13) and install in
valve body.
After any disassembly, reassembly, and/or parts
8. Install cover plate (21) with 5 bolts (23) and replacement in the pressure control valve, clutch
washers (20). Tighten bolts to standard torque. oil pressure must be checked and adjusted if nec-
9. Assemble the connectors (2, Figure 2-39) and (3) essary.
to the bracket.
10. For each ECMV assembly, install O-rings (3
places) at the valve seats and install with 4 bolts
(8). Tighten bolts (11) to 3.15 ± 0.35 kgm (20 - 25
ft.lbs.) torque.

CLUTCH PRESSURE CHECK &
ADJUSTMENT
Note: Prior to checking clutch pressure, test and verify 4. Referring to Figure 2-41, install a pressure gauge
main relief pressure is normal. at the pressure test port of the ECMV for the
clutch to be tested. The gauge should be installed
directly at the pressure test port without the use
1. Park truck on a level surface, raise dump body of a hose.
and lock in raised position with safety pins.
5. Start the engine, allow air pressure to build to
2. Shut down engine and be certain key switch is Off. normal operating range and be certain the park-
3. Install the shift checker (Refer to Figure 2-40): ing brake is applied.
a. Disconnect the chassis harness (6, Figure 6. With the transmission range selector in “N”, turn
2-40) from the transmission control box (4). the shift checker power switch On.
b. Connect shift checker harness (3) (white con- a. Press the clutch operation button for the de-
nectors) to the truck chassis harness connec- sired clutch.
tors (SC1, SC2, SC3 & SC4) removed in step b. With engine at high idle, measure and note the
a. clutch pressure gauge reading.
c. Be certain shift checker power switch is Off. c. After reading is obtained, release accelerator
Connect harness (3) black connector to shift and press button selected in step a. to release
checker. clutch.
7. Shut down the engine and remove the gauge
installed in step 4 and replace port plug.

trucks serial number A10190 or higher, harness con-
nector 799-607-2120 must be used. Or, use shift
checker 799-607-3000 and connect directly to trucks
FIGURE 2-40. SHIFT CHECKER INSTALLATION

1. Shift Checker (Part No. 799-607-2000 or 799-607-3000) 4. Transmission Control Box
2. Harness connector, black (to Shift Checker, see Note above) 5. Harness connectors, white (to Chassis Harness)
3. Harness Assembly 6. Truck chassis Harness (Transmission Control

FIGURE 2-41. CLUTCH PRESSURE TEST PORT IDENTIFICATION
A: High Clutch Pressure Port D: 3rd Clutch Pressure Port F: 2nd Clutch Pressure Port
B: Low Clutch Pressure Port E: Reverse Clutch Pressure Port G: 1st Clutch Pressure Port
C: 4th Clutch Pressure Port
8. Repeat steps 4 through 7 as necessary to check NOTE: One shim (thickness: 0.2 mm) will result in
other clutch pressures. approximately 0.19 kg/cm2 (2.7 psi) variation in the oil
pressure.
9. Compare gauge readings obtained with chart in
(Add shims to increases oil pressure; remove shims to
Figure 2-42.
decrease oil pressure.)
10. If pressure is outside normal range, the pressure
11. If a different shim pack is installed, repeat pressure
control valve spool shim pack (7, Figure 2-39)
test to verify correct clutch pressure has been
must be increased or decreased.
achieved.
12. If no further tests are to be performed, the shift
checker (if installed) may be removed.
a. Disconnect harness connectors (5, Figure 2-
40) from chassis harness (6) and remove shift
PRESSURE checker.
CLUTCH
kg/cm2 PSI b. Reconnect chassis harness connectors to
H 16.5 ±1.5 235 ±20 transmission control box (4).
L 16.5 ±1.5 235 ±20 13. Be certain all pressure test port plugs are installed.
Install protective cover on transmission control
4th 16.5 ±1.5 235 ±20
valve.
3rd 20.5 ±1.5 290 ±20
R 30.5 ±1.5 435 ±20
2nd 31.5 ±1.5 450 ±20
1st 31.5 ±1.5 450 ±20
FIGURE 2-42. CLUTCH PRESSURE

SPECIFICATIONS

LUBRICATION RELEIF VALVE
FIGURE 2-42. LUBRICATION RELIEF VALVE

1. Valve body 2. Lubrication Relief Spool a. Lubrication pressure measurement plug
LUBRICATION RELIEF VALVE
Function Specifications
This valve is installed on the left side of the transmis- Normal Operating Pressure:
sion and prevents abnormal pressure in the transmis- 1.25 ±.5 kg/cm2 (18 ±6 psi)
sion lubrication circuit.
Cracking pressure: 2.7 kg/cm2 (38 psi)

TRANSMISSION
This truck utilizes a Komatsu TORQFLOW remote
mounted transmission. It is a fully automatic shift trans-
mission equipped with a torque converter. The trans-
mission has seven speeds “Forward” and one
“Reverse”.
The transmission has a gear driven, front-mounted
Power Take-Off assembly that drives the steering,
hoist, transmission and brake cooling pumps.
Transmission Removal FIGURE 2-43. ELECTRICAL WIRING
1. Park truck on a level surface, block wheels and 1. Electrical Connectors 2. Brake Cooling Valve
apply park brake. Raise dump body and install
body holding pins. Move hoist valve to “Float”
position to put weight of dump body on pins. Then
lock the hoist lever in the hold position.
Dump body must be up and safety pins in place.

DO NOT work under raised dump body unless the
body pins are installed.
NOTE: If hydraulic pump or engine is inoperative,

dump body should be raised with a crane so body
FIGURE 2-44. ELECTRICAL WIRING
holding pins can be installed.
1. Oil Level Sensor 2. Electrical Connector
2. Turn keyswitch “Off” and shut down engine.
3. Drain transmission oil.
4. Drain approximately one third of the brake oil.
5. Tag and Disconnect transmission control wiring

connectors (1, Figure 2-43).
6. If equipped, disconnect transmission oil level sen-

sor connector (2, Figure 2-44).
FIGURE 2-45. HYDRAULIC LINES

7. Tag and remove 6 pump outlet hoses (2, Figure 1. Housing 2. Hydraulic Hoses
2-45).

8. Remove transmission pump suction tube (1, Fig- 11. On the front drive line, remove drive shaft guard
ure 2-46) Remove clamp (2). (1, Figure 2-49) and drive shaft (2).
FIGURE 2-46. SUCTION TUBE

FIGURE 2-49. FRONT DRIVE LINE
1. Suction Tube 2. Clamp
1. Drive Shaft Guard 2. Drive Shaft
9. Remove pump tubes (1, Figure 2-47) and (2) for

brake pump. 12. On the rear drive line, remove drive shaft guard (1,
Figure 2-50) and drive shaft (2).
FIGURE 2-47. BRAKE PUMP TUBES FIGURE 2-50. REAR DRIVE LINE
1. Tube 2. Tube 1. Drive Shaft Guard 2. Drive Shaft
10. Disconnect pump tubes (1, Figure 2-48) and (2) 13. Remove front mount capscrews (1, Figure 2-51)
for the steering and hoist pump. for transmission assembly.
FIGURE 2-48. STEERING AND HOIST PUMP FIGURE 2-51. FRONT TRANSMISSION MOUNT
1. Tube 2. Tube 1. Transmission Mount 2. Torque Converter

Transmission Installation
NOTE: Check the vibration dampener for wear, dam-
age or deterioration. Replace any rubber cushions or
dampeners in doubtful condition.
Dump body must be up and safety pins in place.

DO NOT work under raised dump body unless the
body pins are installed.
FIGURE 2-52. REAR TRANSMISSION MOUNT
1. Mount 2. Capscrew 1. Install transmission assembly (1, Figure 2-53).
NOTE: See the procedure for centering the engine
assembly and transmission assembly, this section.
2. Install front mount capscrews (1, Figure 2-51) for
13. Remove rear mount capscrews (2, Figure 2-52) for transmission assembly. Tighten capscrews to 56
transmission assembly. ±6 kg.m (406 ±44 ft. lbs.) torque.
3. Install rear mount capscrews (2, Figure 2-52) for
transmission assembly. Tighten capscrews (2) to
56 ±6 kg.m (406 ±44 ft. lbs.) torque.
Use a lifting device capable of safely handling 3178 4. Install rear drive shaft (2) and drive shaft guard (1,
kg (7006 lbs). Figure 2-50). Tighten drive shaft mounting cap-
14 Remove torque converter and transmission as- screws to 18 ±2 kg.m (130 ±14 ft. lbs.) torque.
sembly (1, Figure 2-53) from the top of the frame. 5. Install front drive shaft (2) and drive shaft guard
(1, Figure 2-49). Tighten drive shaft mounting
capscrews to 18 ±2 kg.m (130 ±14 ft. lbs.)
torque.
6. Connect pump tubes (1, Figure 2-48) and (2) for
the steering and hoist pump.
7. Install brake pump tubes (1 & 2, Figure 2-47).
8. Install transmission pump suction tube (1, Figure
2-46) Remove clamp (2).
9. Install the 6 pump outlet hoses (2, Figure 2-45).
10. If equipped, connect transmission oil level sensor
connector (2, Figure 2-44).
11. Connect transmission control wiring connectors
(1, Figure 2-43).
FIGURE 2-53. TRANSMISSION REMOVAL 12. Refill the brake oil tank with oil. Refer to Section
“P”, Lubrication and Service.
1. Transmission Assembly 2. Lifting Chain

13. Refill transmission with oil specified in lube chart
in Section “P”. Check transmission oil level with
truck level, engine running at low idle, lil at oper-
ating temperature and transmission in neutral.
Check the oil level with Bottom sight gauge. Use
the Upper Sight gauge when the engine has been
stopped for 8 hours or more.
FIGURE 2-54. SHAFT ALIGNMENT
Procedure For Centering The Engine Assembly 1. Engine End 3. Torque Converter End
And Transmission Assembly 2. Tool
NOTE: When the engine assembly, torque converter

and transmission assembly, or drive shaft have been
removed, the alignment of the engine and transmis-
sion must be checked and adjusted.
1. Install tool (2, Figure 2-54) to the couplings at the

engine end and torque converter end.
NOTE: To raise transmission, place shims between FIGURE 2-55. SHAFT ALIGNMENT
the front mounts and the frame bracket. 1. Engine End 3. Torque Converter End
2. Tool
2. While turning coupling at torque converter end,
carry out centering so that tool (2, Figure 2-55 and
2-56) rotates smoothly on both shafts. Move the
torque converter and/or transmission assembly
end when centering.
NOTE: The misalignment should be within 3 mm in

both the up-down and left-right directions. However, if
they are not parallel, the distance at the point where FIGURE 2-56. MAXIMUM SHAFT MISALIGNMENT
they are farthest apart must be within 3 mm.

TRANSMISSION FILTER
The transmission filter element (Beta 25 = 200) should

be replaced every 500 hours of operation or sooner if
the warning light indicates high restriction. This main-
tenance interval may be be increased or reduced,
depending on operating conditions, by observing the
warning light indicator.
This filter assembly is equipped with a pressure switch
to indicate a high pressure differential (restriction). The
switch will close @ 2.5 kg/cm2 (35 psi) by-pass pres-
sure. Actual by-pass of the hydraulic fluid does not
occur until 3.5 kg/cm2 (50 psi) by-pass pressure.
Service
1. Remove drain plug (7, Figure 2-57) and drain the

oil from the filter housing. Tighten plug after all oil
is drained.
2. Unscrew filter bowl (4) from head assembly (1).
3. Remove the element and thoroughly clean and
dry all component parts.
4. Coat a new seal (9) with clean engine oil and
install.
5. Install a new element (5) and install the filter bowl
(4) into the head assembly (1).
6. Start the engine and let it idle for 5 minutes. Stop
engine and check for leaks. Check transmission
for proper oil level and adjust if necessary.
FIGURE 2-57. TRANSMISSION FILTER

1. Head Assembly 6. PressureSwitch
2. Core Kit 7. Drain Plug
3. Bypass Valve 8. O-Ring
4. Filter Bowl 9. Seal
5. Filter Element

TRANSMISSION OIL COOLER
Transmission oil cooler repairs should be performed TRANSMISSION STRAINER

by a qualified repair facility. The bottom tank and
gaskets are available as replacement components. The transmission oil pan contains two magnetic strain-
Contact your Komatsu distributor. ers. It should be removed and cleaned every 1000
hours.
The bottom tank of the radiator contains the heat
exchanger for the transmission. If a leak occurs in the Removal
heat exchanger, antifreeze/coolant may contaminate
the transmission oil and/or transmission oil may con- 1. Drain transmission oil. Be prepared to catch 106
taminate the engine cooling system. l (28 gal) of oil.
If the engine coolant is found to be contaminated with 2. Remove capscrews (5, Figure 3-1) and cover (3).
oil, the system must be examined for leaks and cor- 3. Remove screen\magnet and clean. Replace if
rected. Then the system must be flushed to remove oil damaged.
contamination and refilled with a clean coolant solu-
tion.
If a leak has been found or suspected in the heat
exchanger, the transmission oil must be examined Installation
IMMEDIATELY. Ethylene glycol (even in small
1. Install screen\magnet into transmission oil pan.
amounts) will damage friction-faced clutch plates.
Contact your Komatsu distributor for ethylene glycol 2. Install new O- Rings (2) in cover and install cover
detection test kits. with capscrews (5).
If ethylene glycol is found in the transmission oil, the 3. Fill transmission with oil. Refer to fuel, coolant and
transmission should be removed, completely disas- lubricants table for type of oil to use.
sembled, cleaned and examined, and ALL friction-
faced clutch plates replaced.
Removal And Installation
Refer to Section "C", Engine, Fuel, Cooling And Air

Cleaner, for the removal and installation of the radiator.
Repair
Repairs to transmission cooler and wet disc brake heat

exchanger should be done by a qualified repair facility
The Wet Disc Brake heat exchanger is also mounted
below the radiator tank. Refer to Section C. "Engine,
Fuel, Cooling And Air Cleaner" for removal and repair.
FIGURE 3-1.
1. Screen\Magnet 4. Washer
2. O-Ring 5. Capscrew
3. Cover
F03004 9/97 Transmission Oil Cooler F3-1

TORQUE CONVERTER CONTROL
VALVE
Removal
1. Raise the dump body and lock with the safety pin.
2. Remove cover (2, Figure 3-2) and hose (1).
3. Disconnect lockup solenoid valve wiring connec-
tor (1, Figure 3-3).
4. Disconnect tube (3).
5. Remove torque converter control valve assembly
(2).
FIGURE 3-3. CONTROL VALVE MOUNTING

Installation
1. Connector 3. Tube
1. Install torque converter control valve and tighten
2. Control Valve
capscrews to 5 kg.m (36 ft. lbs.)
2. Connect tube (3, Figure 3-3).
3. Connect lockup solenoid valve wiring connector
(1).
4. Install cover (2, Figure 3-2) and hose (1).
Disassembly
1. Remove plate (1, Figure 3-4), then remove pistons
(2) and (4), spring (3), and torque converter relief
valve (5).
2. Remove cover (6), then remove spring (7).
3. Remove cover (8), then remove spring (9).
4. Remove plate (10), then remove pistons (11) and
(13), spring (12), and main relief valve (14).
5. Remove cover (15), then remove piston (16),
spring (17), and ring (18).
6. Remove cover (19), then remove pistons (20) and
(22), spring (21), and lockup valve (23).
FIGURE 3-2. CONTROL VALVE
1. Hose 2. Cover
F3-2 Transmission Oil Cooler F03004 9/97

Assembly
NOTE: Clean all parts, and check for dirt or damage. 3. Insert main relief valve (14), assemble pistons
coat the sliding surfaces of all parts with engine oil (13) and (11), and spring (12), then fit O-ring and
before installing. install plate (10).
1. Insert lockup valve (23), assemble pistons (22) 4. Assemble spring (9), then fit O-ring and install
and (20), and spring (21), then fit O-ring and cover (8).
install cover (19).
5. Insert torque converter relief valve (5), assemble
2. Fit ring (18) and assemble spring (17) and piston spring (7), then fit O-ring and install cover (6).
(16), then fit O-ring and install cover (15).
6. Assemble pistons (4) and (2), and spring (3), then
fit O-ring and install plate (1).
FIGURE 3-4. TORQUE CONVERTER CONTROL VALVE
1. Plate 7. Spring 13. Pistons 19. Cover

2. Pistons 8. Cover 14. Main Relief Valve 20. Pistons
3. Spring 9. Spring 15. Cover 21. Spring
4. Pistons 10. Plate 16. Piston 22. Pistons
5. Relief Valve 11. Pistons 17. Spring 23. Lockup Valve
6. Cover 12. Spring 18. Ring
F03004 9/97 Transmission Oil Cooler F3-3

NOTES
F3-4 Transmission Oil Cooler F03004 9/97

DRIVELINES
The engine/transmission and transmission/final drive
drivelines are different. The front driveline is approxi-
mately 45 cm (18 in.) and is solid, the rear is approxi-
mately 127 cm (50 in.) in length and telescopes.
Removal
Removal and installation procedures for each driveline
are identical.
Block wheels securely before removing the driveli-

nes.
1. Remove driveline protector if equipped.

FIGURE 5-1. TYPICAL FRONT DRIVELINE
2. Remove and tag any wiring or hoses which may INSTALLATION
interfere with removal.
1. Flywheel Adapter Cover 3. Capscrews
2. Attach a sling hoist to the driveline.
2. Front Driveline 4. Transmission
3. Remove the four capscrews at each cross and
bearing and remove the driveline.
Note: Do not disassemble the cross and bearings. If
Installation bearings are unserviceable, replace the entire part as
1. Position driveline between transmission (or final a unit.
drive) and align the cross and bearings with the 2. Clean all parts except the cross and bearing in
drive flanges. fresh solvent and blow dry with compressed air.
2. Install the capscrews and tighten to the following 3. On rear drive shaft, mark the shafts for proper
torque :18 ± 2 kg.m (130 ± 14 ft.lbs.) torque orientation during assembly to maintain the bal-
Front Driveline: ance on the shaft. Inspect all parts for wear and
18 ± 2 kg.m (130 ± 14 ft.lbs.) damage. If either the stub or yoke is unservice-
able, parts must be replaced with a new, balanced
Rear Driveline:
and matched set
18 ± 2 kg.m (130 ± 14 ft.lbs.)
4. Insure all grease passages are clear.
3. Install driveline protector if equipped. Tighten cap-
screws to standard torque Assembly
4. Install wiring or hoses removed to gain access to 1. Lubricate the splines with multi-purpose grease,
driveline. and carefully slide together with balance marks
lined up.
Disassembly
2. Attach the cross and bearings at each end. Tighten
1. Remove the capscrews and cross and bearing capscrews to 18 ± 2 kg.m (130 ± 14 ft.lbs.)
from each end of driveline and inspect for rough torque.
or frozen bearings.
3. Install grease fittings if removed, and lubricate with
multi-purpose grease. (Refer to Section “P” for
complete grease specification.)
F05004 Drivelines F5-1

NOTES
F5-2 Drivelines F05004

AUTOMATIC SHIFT CONTROL SYSTEM
GENERAL INFORMATION TRANSMISSION SHIFT CONTROLLER
Operation of the transmission is controlled by the The Transmission Shift Controller is designed to con-
Transmission Shift Controller as shown in Figure 6-2. trol the transmission and communicate with other sys-
Various inputs are provided to the controller allowing tems on the truck. This communication is based on
it to provide optimum transmission performance during various inputs and outputs from sensors and other
truck operation. system controllers.
The system monitors the following operator inputs
during normal operation: POWER MODE
• Accelerator pedal position There are two power mode settings; Power and Econ-
• Range Selector position omy.
• Shift limiter switch position Power Setting:
Other inputs are provided by various switches in the • The engine controller allows full fuel to flow to
service brake, parking brake and retarder systems as provide maximum rated engine power. The
well as the position of the hoist control. Speed sensors transmission controller controls the up and
provide signals for engine rpm and transmission input down shift points.
shaft, output shaft, and intermediate shaft speeds.
Economy Setting:
After processing the input information, the Transmis- • The engine controller reduces the fuel flow
sion Shift Controller determines the proper mode of since full power is not required. The transmis-
operation by engaging the proper gear, controlling sion controller modifies and controls the up and
lock-up clutch operation, etc. down shift points.
Gear selection is achieved by the engaging or releas-
ing the required transmission clutches through elec- BRAKING MODE
tronically controlled modulation valves (ECMV) as • In the braking mode, (brake foot pedal, retarder
determined by the Transmission Shift Controller. The lever, or emergency brake applied) the up and
current gear selected is displayed on the instrument down shift points are raised, increasing the
panel during operation. brake cooling pump speed (and therefore oil
volume) to ensure adequate cooling of the
brake cooling system oil.
At the same time, it increases engine rpm which
improves the the effect of using the engine as a
brake.
LOCK-UP AND ENGINE OVERSPEED

• The transmission controller senses different
speeds to drive and control the torque converter
lock-up solenoid valve, overrun protection sole-
noid, BCV solenoid, and if equipped, the ex-
haust brake solenoid.
TRANSMISSION SPEEDS MONITORING

• Speed sensors are installed at three places (on
the transmission input shaft, intermediate shaft,
and output shaft.) These sensors are used to
detect if a transmission clutch is slipping, and
also act to protect the transmission when there
is some abnormality in the hydraulic system.
F06005 Automatic Shift Control System F6-1

SELF DIAGNOSTICS
• A self-diagnostic function monitors both the in-
puts and outputs of the transmission.
• The transmission controller contains a self-di-
agnostic display (1, Figure 6-1) and is shown in
a two-digit number display located on the top of
the controller. When a fault is detected, it is
recorded in memory. The fault is stored in mem-
ory and is retained even if the power is turned
off. When power is turned on again, the fault
code can be observed as the controller is pow-
ered-up.
• Detected faults are also sent to the network by
the controller, and displayed on the monitor
display panel (dash panel).
• The transmission controller communicates with
other controllers on the truck via the network. It
receives model selection data from the other
controllers.
• The transmission controller receives inputs
from various sensors and switches (see Figure
6-2). These inputs are interpreted by the trans-
mission controller and then sent to the monitor
display panel and other functions. FIGURE 6-1. TRANSMISSION SHIFT
CONTROLLER
• The controller also has an emergency function
for use if there is a failure in the electrical 1. Self-diagnostic Display 6. Connector ATC4
system. 2. Network Connection 7. Connector ATC5A
Switch (Rotary Switch 2) 8. Connector ATC5B
3. Model Selection Switch 9. Connector ATC1
(Rotary Switch 1) 10. Connector ATC2
4. Connector ATC3A
5. Connector ATC3B
F6-2 Automatic Shift Control System F06005

FIGURE 6-2. AUTOMATIC SHIFT CONTROL SYSTEM

RANGE SELECTOR POSITIONS AND TRANSMISSION OPERATION MODES
AUTOMATIC GEAR SHIFTING RANGES Transmission upshifts or downshifts are determined by
The automatic gear shifting ranges for each position three types of “shift maps” programmed into the Trans-
of the Range Selector lever are shown in the table in mission Shift Controller. The table in Figure 6-4 below
Figure 6-3. shows the conditions that must be satisfied for the
Transmission Shift Controller to select either the brak-
Note that when the operator selects “D”, the recom- ing mode or the power mode.
mended range for normal operation, the transmission
controller will engage 2nd range and automatically
shift through the 3rd through 7th gear ranges as re- MODE CONDITIONS
quired. This will result in the most economical opera- When either of the following
tion. If the operator selects “3”, “4”, or “5”, the conditions are satisfied:
transmission will initially select 1st range and then Braking 1. Rear brake signal ON (service
upshift only as far as the range selected. These posi- Mode brake, retarder, or emergency brake
tions provide more effective retarding on grades. applied)
The Shift Limiter switch, located on the center console 2. Accelerator pedal released.
in the cab can be used to limit the shift ranges in the When the following three conditions
“D” and “L” shift lever positions. are satisfied:
1. Rear brake signal OFF (service
If the operator has selected the “D” range, the shift Power
brake, retarder, or emergency brake
limiter switch, when turned On, will prevent the trans- Mode
not applied)
mission from shifting into 7th range to limit top speed.
2. Accelerator pedal depressed.
The shift limiter switch can also be used to hold the 3. Economy mode switch OFF.
transmission in 1st range when the operator has se- When the following three conditions
lected the “L” position on the shift lever. are satisfied:
1. Rear brake signal OFF (service
Economy
brake, retarder, or emergency brake
Mode
Selector Shift Speed Range not applied)
Position Limiter 2. Accelerator pedal depressed.
R N 1 2 3 4 5 6 7
3. Economy mode switch ON.
OFF •
R
ON •
FIGURE 6-4. OPERATIONAL MODES
OFF •
N Braking Mode:
ON •
In the braking mode of operation, the shift-down point
OFF and shift-up point are both raised, and the engine rpm
D
ON speed is increased to provide additional oil flow for
OFF retarder cooling, and to increase the effect of using the
5 engine as a brake.
ON
OFF Power Mode:
4
ON
The power mode is programmed to provide maximum
OFF performance by using the trucks’ power to its utmost
3
ON limit by optimizing the shift points according to the rate
OFF of acceleration determined by the load, grade etc.
L
ON • When the truck is not loaded, the system senses the
increased rate of acceleration and shifts to a higher
gear range sooner than if the truck were loaded. This
FIGURE 6-3. SHIFT RANGE/SHIFT LEVER improves acceleration and reduces haul cycle time.
POSITIONS

These variable performance features improve fuel 2. In power mode, the shift-up point from F1 to F2,
economy, reduce noise and reduce shift shock to is 2100 rpm. The shift-down point from F2 to F1
improve transmission and driveline component life. is 1400 rpm.
Economy Mode:
3. Lock-up
When the truck is operating with a light load, such as
traveling empty or when traveling on flat ground, the • Lock-up is not actuated in reverse.
shift-up and shift-down points are set lower to keep the • When coasting and decelerating (accelerator
engine speed low, improving fuel consumption, reduc- pedal released, and brake not applied), for
ing noise, and shock when shifting gears. In this mode, positions F7 - F4, the lock-up solenoid is mo-
engine output is limited to 85% of maximum engine mentarily turned off during the down-shift from
power. one gear to the next. For F3 and below, the
lock-up solenoid is turned OFF.
• When the truck descends a grade with the
accelerator pedal released, lock-up is not ac-
AUTOMATIC GEAR SHIFTING tuated until the accelerator pedal or the brake
The automatic shift-up/shift-down points, torque con- pedal is depressed.
verter lock-up ON/OFF points and auto brake ON/OFF
points are shown in Figure 6-5.
Note: F1, F2, etc. refers to 1st, 2nd etc. transmission
gear ranges.
AUTOMATIC SHIFTING SEQUENCE
Conditions: Range Selector position: D

Shifting UP in power mode
1. If the Range Selector lever is placed in the “D”

position, the transmission will shift to F2, torque
converter range.
2. When the accelerator pedal is depressed, the
engine speed will rise. When the transmission
input shaft speed reaches 1500 rpm, the lock-up
clutch is engaged to connect the torque converter
directly, eliminating slippage.
3. When the input shaft rpm increases to 2100 rpm,
the transmission is shifted up to F3. At the shift-up
point, the lock-up clutch is automatically disen-
gaged momentarily to reduce shock during the
gear change.
4. Immediately after shift up, the engine speed
drops, but if the load is small, the engine speed
FIGURE 6-5. GEAR SHIFTING GRAPH rises again. The situation in step 2. is repeated
and the transmission is shifted up sequentially
NOTE: from F4 to F7.
1. In the economy mode, the shift-up point from F1

to F2 is 2000 rpm. The shift-down point from F2
to F1 is 1300 rpm.

Conditions: Range Selector position: D Gear shifting time lag
Shifting DOWN in power mode A time lag is incorporated to prevent excessive speed
changes in the transmission during automatic gear
changes. This time lag prevents a gear shift during a
1. When the load is increased and the engine speed
predetermined period of time.
drops below 1450 rpm, the transmission is shifted
down one gear. (For example, when traveling in The length of the gear shifting time lag is controlled by
F6, the transmission will shift down to F5) the individual electronically controlled modulation sys-
tem, which controls each gear shifting pattern as
2. If the load increases further, the transmission
shown in Figure 6-6.
shifts down sequentially to F2. If the input shaft
speed drops to 1200 rpm when the transmission
is in F2, the torque converter lock-up clutch is
disengaged and the transmission changes to
torque converter drive.
NOTE: The above explanation gives a general outline

of gear shifting. However, the set speed and actuation
may differ according to conditions.
Conditions: Range Selector position: 5, 4,

3, or L
1. These positions give an automatic shift range from

F1 to F5 (F4, F3, or F2). The method for automatic
shifting is the same as when the shift lever is at
the D position.
FIGURE 6-6. GEAR SHIFTING TIME LAG
Conditions: Range Selector position: R

1. This is the position for traveling in reverse.
The lock-up is not actuated.
The safety functions when traveling in reverse
include the FORWARD/REVERSE inhibit and
REVERSE safety. If the operation is not correct,
the transmission is held in neutral.
Conditions: Range Selector position: N

1. This is the neutral position. None of the clutches
in the transmission are actuated.

SAFETY FUNCTIONS REVERSE safety:
•The truck will not travel in reverse when the
Down-shift inhibitor function:
dump body is in any position other than
• When the gear shift lever is operated during FLOAT.
travel from D to 5 - L, from 5 to 3 - L, from 4 to
L, or from 3 to L: This feature prevents the truck from inadvertently re-
versing when the body is raised.
For example, when traveling at position D (F7), and
the shift lever is moved to position 5, the transmission
is not shifted directly from F7 to F5. It is shifted down
Speed range limit with dump body raised:
F7 - F6 - F5 sequentially according to the engine
speed. The engine overspeed prevention circuit pre- • If the dump body is not in the completely down
vents the transmission from shifting down two gears at position (i.e. if not completely lowered after
a time if the operator shifts down too far. dumping the payload), the up shift function is
prohibited. When the shift lever is in “D”, the
truck will start in F2. If the lever is in any other
position, the truck will start in F1.
Neutral safety function:
The transmission controller will not allow an
• If the shift lever is in any position other than N, upshift until the dump body is in its down posi-
this circuit prevents the engine from starting tion.
when the key switch is turned to the START
position.
The neutral safety circuit prevents the truck from mov-
ing when the engine is started.
FORWARD/REVERSE inhibitor function:

• When the truck is traveling forward at more than
2.5 MPH (4 km/h), the transmission will not
engage REVERSE if the Range Selector lever
is placed in the R position.
Rear brake application for power train over-

speed prevention:
• When the engine speed exceeds 2500 rpm, the
central warning lamp flashes and the alarm
buzzer sounds.
• If the engine speed exceeds 2600 rpm, the rear
brake is automatically applied.
This feature improves durability and reliability by pre-
venting engine, torque converter and transmission
overspeed.

TRANSMISSION RANGE SELECTOR
When the operator moves the lever (1, Figure 6-7) to The shift position is also displayed on the monitor
select the travel conditions, such as FORWARD or panel digital display.
REVERSE, an electrical signal is sent from a photo The lock button (1, Figure 6-8) must be pressed when
interrupter (3, Figure 6-8) to the transmission shift moving the range selector lever from “N” to “R” or from
controller. The lever position is displayed on the indi- “D” to “5”.
cator (3, Figure 6-7) (with night lighting) to the left of
the shift lever.
FIGURE 6-7. TRANSMISSION RANGE SELECTOR FIGURE 6-8. TRANSMISSION RANGE SELECTOR
(Cross-sectional View)
1. Lever 3. Range Indicator
2. Detent
1. Lock Button 3. Photo Interrupter
2. Screening Plate

SENSORS, SWITCHES
Transmission Speed Sensors

Speed sensors are installed to monitor the rpm of the
input, intermediate, and output gears of the transmis-
sion. The sensors generate a pulse voltage which
varies with the speed of the gear teeth passing the
sensor, sending a signal to the Transmission Control-
ler.
The sensors must be adjusted correctly to ensure an
adequate electrical signal is generated. If necessary, FIGURE 6-10. SPEED SENSOR ADJUSTMENT
adjust as follows:
1. Sensor 3. Gear Tooth Tip
Adjustment Procedure 2. Locknut a. Clearance Gap
1. Disconnect wire connector (1, Figure 6-9), release
locknut (4), and remove sensor. Observe location
of gear teeth through sensor mounting hole. For
proper adjustment, the tip of a gear tooth must
be aligned with the sensor hole as shown in
Figure 6-10. If necessary, reposition gear.
2. Inspect sensor for iron particles or other foreign
material and clean if necessary.
3. Reinstall sensor. Adjust by hand until it just con-
tacts the gear tooth.
4. Turn counterclockwise 3/4 turn to obtain proper
clearance (“a”, Figure 6-10) and tighten locknut.
5. Reinstall wire connector.
FIGURE 6-9. TRANSMISSION SPEED SENSOR
1. Connector 3. Sensor
2. Flange 4. Locknut

Transmission Oil Temperature Sensor Fill Switch
This transmission oil temperature sensor is installed at A Fill Switch is installed at the flow sensor valve end
the transmission filter. As temperature changes occur of each Electronic Control Modulation Valve (ECMV)
in the oil, resistance of the sensor thermistor (1, Figure as shown in Figure 6-12. When the clutch is engaged,
6-11) changes, providing a calibrated electrical signal the end face of the flow sensor valve spool (2) contacts
to the Transmission Controller. the terminal (1, Figure 6-13) of the switch and turns the
switch ON. The fill completed signal is then sent to the
Transmission Controller.
FIGURE 6-11. TRANSMISSION OIL

TEMPERATURE SENSOR
1. Thermistor 3. Connector
2. Body
FIGURE 6-12. ECMV FILL SWITCH
1. ECMV Assembly 3. Fill Switch
2. Flow Sensor Valve Spool
FIGURE 6-13. FILL SWITCH
1. Terminal 3. Nut
2. Case 4. Connector

Shift Limit Switch
The Shift Limit Switch is installed on the console, to
the rear of the Transmission Range Selector. When
the range selector lever is in the “D” or “L” range, it
limits the highest speed range of the transmission.
If the switch is released and the range selector is
placed in “D”, the transmission will engage F2 and shift
up through F7 during acceleration. If the switch is
depressed and the selector is in “D”, the transmission
will operate in F2 through F6 gear ranges.
If the range selector is placed in “L” and the switch is
released, the transmission will engage F1 and only
upshift as far as F2. If the switch is depressed with the
range selector in “L”, F1 will engage and no upshifts
will occur.
This switch is very effective if used when descending
a hill or when working at job sites where speed must
be limited.
Power Mode Switch

The Power Mode Switch is located on the console, just
behind the Shift Limit Switch. When the switch is
released, it is in the “power mode” (switch out, light off)
position.
The controllers (engine and transmission) are pro-
grammed to provide maximum power by optimizing the
shift points according to the rate of acceleration deter-
FIGURE 6-14. SHIFT LIMIT & POWER MODE
mined by the load etc.
SWITCH
When the Power Mode Switch is depressed, it is in the
“economy mode” (switch latched in, light on) position.
The controllers (engine and transmission) are pro-
grammed to lower the up and down shift points to keep
the engine speed low. In addition, engine output is
limited to approximately 85% of maximum power.
Note: When these switches are actuated, an internal

lamp will illuminate (see schematic in Figure 6-14).

TRANSMISSION TROUBLESHOOTING Clutch Combinations
PROCEDURES The table below lists the clutches engaged (X) for each
The following pages contain charts listing information speed range. This information is necessary when di-
which may be used to help diagnose and troubleshoot agnosing ECMV and internal transmission problems.
transmission problems which may be encountered.
CLUTCH Hi Lo 4th 3rd R 2nd 1st
No. 1 2* 3* 4 5 6 7
Prior to detailed troubleshooting, check for obvious SPEED
reasons for the problem such as: RANGE
R X X
Is the transmission oil level correct? N

Are the drive shafts broken or damaged? F1 X X
Is the input shaft of the torque converter or F2 X X

transmission broken? F3 X X
Are the service brakes, parking brake or re- F4 X X
tarder dragging? F5 X X
Is there any physical damage to the transmis- F6 X X
sion or torque converter cases?
F7 X X
Is there any external oil leakage?
Are all electrical connectors tight? * Rotating
Is there any damage to wiring harnesses?
Solenoid Valves
If visual inspection of the above items does not reveal The table below lists the state of the transmission
an apparent reason for the problems, refer to Section solenoid valves (or fill sensor) for each of the transmis-
D, “Hydraulic and Mechanical Systems Troubleshoot- sion range selector positions.
ing” for detailed troubleshooting procedures.
Trans. Solenoid
Valve (Fill Sensor)
H L R 1 2 3 4
R H L L H H H H
N H H H H H H H
Shift 1 H L H L H H H
Indicator 2 H L H H L H H
Speed
Range 3 L H H H L H H
Display 4 H L H H H L H
5 L H H H H L H
6 H L H H H H L
7 L H H H H H L
H = Open or 24VDC
L = GND or 1.7VDC

HARNESS CONNECTORS AND SIGNALS
The following charts should be used in conjunction with
the electrical schematic (Section R) when diagnosing
transmission controller wiring harness problems, sen-
sor problems, etc.
CONNECTOR: ATC1 CONNECTOR: ATC2

PIN No. SIGNAL PIN No. SIGNAL
1 L/C SOL 1 Proportional SOL power source 24V
2 2 ECMV 1st (+)
3 3 ECMV 3rd (+)
4 Overrun SOL (+) 4 ECMV 2nd (+)
5 Exhaust brake SOL (+) 5 ECMV R (+)
6 Accelerator low idle 6
7 Battery direct power source 7 ECMV L (+)
8 GND 8 ECMV 4th (+)
9 Power source, 24V 9 ECMV H (+)
10 10
11 BCV 11
12 12 Proportional SOL power source 24V
13 Overrun SOL (-) 13 ECMV 1st, 3rd (-)
14 Exhaust brake SOL (-) 14 Sensor power source 12V
15 Transmission cut relay 15 ECMV 2nd, R (-)
16 GND 16
17 Power source 24V 17 ECMV L (-)
18 ECMV 4th (-)
19 ECMV H (-)
20 Solenoid L/C (-)
21 GND

CONNECTOR: ATC3A CONNECTOR: ATC3B
1 1 Alternator terminal R
2 Transmission input shaft speed 2 Brake air pressure
3 Transmission output shaft speed 3
4 Shift wait 4 Fuel level
5 Throttle correction 5 Engine water temperature
6 Potentiometer power source 5V 6
7 7 Torque converter out oil temperature
8 8 Rear brake oil temperature
9 Transmission oil level Transmission valve inlet port oil
9
10 Limp home ON/OFF temperature
11 Steering oil temperature 10
12 Transmission intermediate shaft speed 11 Accelerator angle
13 Engine speed 12 Engine oil pressure
14 GND (pulse) 13
15 Brake Command 14
16 GND (analog) 15 Differential lock switch
17 16
18
19
20
CONNECTOR: ATC4
PIN No. SIGNAL
1 RS422 TX (+)
2 RS422 RX (+)
3 RS232C TX
4 RS232C RX
5 RS485 (+)
6 S-NET (+)
7 RS422 TX (-)
8 FLASH switch
9 RS422 RX (-)
10 GND (serial)
11 RS485 (-)
12 S-NET (-)

CONNECTOR: ATC5A CONNECTOR: ATC5B
1 Connector check 1 Exhaust brake ON/OFF
2 Rear brake ON/OFF 2 Shift lever R signal
3 Body FLOAT signal 3 Shift lever N signal
4 Body seated signal 4 Shift lever D signal
5 Lateral inclination 5 Shift lever 5 signal
6 Transmission filter restriction 6 Shift lever 4 signal
7 7 Shift lever 3 signal
8 Brake stroke switch 8 Shift lever L signal
9 9 Shift limit switch ON/OFF
10 Fill switch LOW 10 Model selection 1
11 Fill switch 4th 11 Model selection 2
12 Fill switch HIGH 12 Model selection 3
13 Fill switch 1st 13 Model selection 4
14 Fill switch 2nd 14 Parking brake ON/OFF
15 Fill switch 3rd 15 Coolant level
16 Fill switch REVERSE 16 Power mode ON/OFF
17 Retarder switch ON/OFF
18 Start signal, key switch C
19 Emergency steering
20 Heater relay ON/OFF
CONNECTOR: ATC6
PIN No. SIGNAL
1 RS232 TX
2 RS232 RX
3 Flasher switch ON/OFF
4 Signal GND

NOTES

SECTION G
WHEELS, SPINDLES AND FINAL DRIVE
INDEX
TIRES AND RIMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-1

TIRES AND RIMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-1
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-1
FRONT TIRE AND RIM
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-2
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-2
REAR TIRE AND RIM
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-4
TIRE MATCHING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-6
FRONT WHEEL HUB AND SPINDLES

FRONT WHEEL HUB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-1
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-1
Front Wheel Bearing and Brake Disc Replacement . . . . . . . . . . . . . . . . . . G3-2
Front Wheel Hub Installation and Bearing Adjustment . . . . . . . . . . . . . . . . . G3-3
A-Frame
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-4
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-4
FINAL DRIVE ATTACHMENTS

FINAL DRIVE LOWER LINK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-1
Pin Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-1
Pin Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2
Bearing Removal and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2
Bearing Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2
DIAGONAL PANHARD ROD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2
Bearing Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-3
G01011 Index G1-1

FINAL DRIVE ASSEMBLY
COMPLETE FINAL DRIVE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-1
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-4
DIFFERENTIAL CARRIER ASSEMBLY -
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-5
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-6
Differential Cage Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-7
Pinion Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-7
Differential Cage Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-7
Spider Gear Bearing Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-9
Spider Gear Bearing Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-11
Differential Cage Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-14
Pinion Installation And Bearing Adjustment . . . . . . . . . . . . . . . . . . . . . G5-14
Differential Cage Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-14
Carrier Bearing And Backlash Adjustment . . . . . . . . . . . . . . . . . . . . . . G5-15
FINAL DRIVE PLANETARIES AND WHEEL HUBS

PLANETARY DRIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-1
Final Drive Carrier Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-2
Final Drive Carrier Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-3
Final Drive Carrier Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-3
Final Drive Carrier Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-4
Final Drive Disasembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-4
Final Drive Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-7
G1-2 Index G01011

TIRES AND RIMS
General Information and Recommendations
The truck tires should be inspected and tire pressure
checked with an accurate pressure gauge before each
working shift. Tire pressure will vary according to • NEVER overinflate a tire. Refer to tire manufac-
manufacturer and local working conditions. Consult turers recommendations.
the tire manufacturer for recommended tire pressure. • ALWAYS keep personnel away from a wheel
Insure valve caps are securely applied to valve stems. and tire assembly when it is being removed or
The caps protect valves from dirt build up and damage. installed.
DO NOT bleed air from tires which are hot due to • DO NOT go near tires after brake fires until tires
operation; under such circumstances, it is normal for have cooled.
pressure to increase in the tire due to expansion.
• The tire and rim weigh approximately 2,800 lbs.
A bent or damaged rim which does not support the (1271 kg). BE CERTAIN tire handling equip-
bead properly may cause abnormal strain on the tire ment is capable of lifting and manuevering the
resulting in a malfunction. If a tire should become load.
deeply cut, it should be removed and repaired. Ne-
glected cuts cause many tire problems. Water, sand, Manual tire removal and installation is possible but, due
grit, dirt and other foreign materials work into a tire to the size and weight of the components, special
through a cut eventually causing tread or ply separa- handling equipment such as a “tire handler” as shown
tion. in Figure 2-1 is desirable. Consult local tire vendors for
Tires should be stored indoors, if possible. If stored sources of equipment designed especially to remove,
outdoors, cover tires with tarpaulin to keep out dirt, repair, and install large off-highway truck tires.
water and other foreign materials. Long exposure to
the sun will cause ozone cracks. Storage should be in
a cool, dry, dark, draft free location. Tires should be
stored vertically. If they must be laid on their sides for
a short period, avoid distortion by stacking no more
than three tires on top of one another. Avoid contact
with oil, grease and other petroleum products.
Before storing used tires, clean thoroughly and inspect
for damage. Repair as necessary. When a truck is
placed in storage, it should be blocked to remove the
weight from the deflated tires. If a stored truck cannot
be blocked, check air pressure and inspect tires twice
a month for proper inflation pressure.
• DO NOT weld or apply heat on the rim assem-

bly with the tire mounted on the rim. Resulting
gases inside the tire may ignite causing explo-
sion of tire and rim.
• When inflating tires ALWAYS use a safety cage.
• NEVER inflate a tire until the lockring is se-
curely in place.
• DO NOT stand in front of or over the lock ring
FIGURE 2-1. TYPICAL TIRE HANDLER
during inflation procedures.
G02010 Tires and Rims G2-1

FRONT TIRES AND RIMS 3. Release air from tire.
4. Grasp tire assembly with the tire handler.
Removal
1. Stop the machine on level ground, apply parking
brake and put blocks on both sides of the rear
wheels.
Do not damage the tire inflation stem during tire
2. Place a 50 ton capacity or larger hydraulic jack (1, removal.
Figure 2-2) under the suspension cylinder on the
A-Frame and jack up the front wheel assembly
and block up securely.
Due to its size and weight, always keep personnel

away from a wheel and tire assembly when it is
being removed or installed.
5. Remove wheel clamp nuts (3, Figure 2-3) and

retainers (2).
6. Move wheel and tire assembly away from wheel
hub and into clean work area.
7. Inspect brake components for damage or wear.
Inspect hydraulic brake lines for leaking fittings or
damage.
FIGURE 2-2. JACK PLACEMENT

1. Jack (50 ton capacity) 2. A-Frame
When deflating tires, be wary of flying dirt and

debris. Wear eye protection at all times.
Do not totally deflate tire. Keep tire inflated to 10-15

FIGURE 2-3. FRONT WHEEL HUB
psi (69-103 kPa) to assure tire and rim components
remain assembled during tire handling.
1. Hub 3. Nuts
2. Retainer 4. Rim
G2-2 Tires and Rims G02010

REAR TIRE AND RIM
Installation Removal
NOTE: Remove all dirt and rust from mating parts
before installing wheel assembly.
1. Stop the machine on level ground, apply parking
brake, and put blocks on both sides of the front
wheels.
1. Grasp tire assembly with the tire handler and move
into position on wheel hub. Align the notch in the
wheel hub with the wheel rim stopper.
2. Raise final drive enough for tires to clear the
ground surface to be removed. Block the final
drive case securely.
2. Install wheel retainers (2, Figure 2-3) and nuts (3).
Tighten the wheel clamp nuts uniformly. Rotate
the wheel, then check that the runout is within 5
3. Remove air valve lock plate (1, Figure 2-4)
mm. (0.20 in.)
4. Remove clamp nuts (2) retainers (4) and wedge

3. Continue tightening nuts in increments until 225
ring (3).
± 25 kg.m (1630 ± 181 ft. lbs.) torque is obtained
on each nut.
5. Position tire removal apparatus (tire handler, fork-
lift, etc.) and remove outside wheel assembly.
4. Check tire inflation for tire manufacturer’s recom-
mended pressure. Raise truck and remove all
blocking.
5. Operate truck for one load and tighten wheel nuts

again to 225 ± 25 kg.m (1630 ± 181 ft. lbs.).
Check torque daily until 225 ± 25 kg.m (1630
± 181 ft. lbs.) torque is maintained on each nut.
Check torque intermittently thereafter.
FIGURE 2-4. RIM AND CLAMPS

1. Air Valve Lock Plate 3. Retainer Ring
2. Clamp Nuts 4. Retainer

6. Remove spacer (2, Figure 2-5). INSTALLATION OF REAR WHEEL ASSEMBLY
1. Clean all tire mounting surfaces.

lift, etc.) and install inboard tire assembly (2, Fig-
ure 2-6). Align the notched groove in the wheel
hub with the wheel rim stopper. Be careful not to
break the air valve.
3. Install the three retainers and clamp nuts (1).

Tighten clamp nuts uniformily in the correct order
of tightening as shown in Figure 2-7. Tighten
clamp nuts to 225 ± 25 kg.m (1630 ± 181 ft. lbs.)
FIGURE 2-5. SPACER AND TIRE torque.
1. Final Drive Housing 2. Spacer
4. Install spacer (2, Figure 2-5).
7. Remove the three clamp nuts (1, Figure 2-6) and
retainers.
NOTE: Be careful not to break the air valve of the lift, etc.) and install outboard wheel assembly.
inboard wheel assembly. Align the notched groove in the wheel hub with
the wheel rim stopper. Be careful not to break the
air valve.
8. Remove inboard tire assembly (2).
9. Place tires off to one side lying flat. Do not lean on

truck, walls, etc.
FIGURE 2-7. TIGHTENING SEQUENCE

1. Clamp Nut
FIGURE 2-6. INBOARD WHEEL ASSEMBLY
1. Clamp Nut 2. Inboard Tire

6. Install the wedge ring (3, Figure 2-4) so that the 9. Rotate the wheel and check that the runout is
protrusion of the wedge ring from the cover sur- within 5 mm. (0.20 in.)
face is uniform around the whole circumference
of the ring. Install clamp nuts (2).
10. After installing the rear wheel assembly, travel
approx. 5 - 6 km (3-4 miles) to settle all contacting
7. Install air valve lock plate (1, Figure 2-4) portions, then tighten clamp nuts again to 225 ± 25
kg.m (1630 ± 181 ft. lbs.) torque. Check torque
periodically until proper torque is maintained.
8. Lower the machine to the ground. Tighten clamp
nuts (1, Figure 2-8) uniformily in the order of
tightening shown in Figure 2-7. Tighten clamp
nuts to 225 ± 25 kg.m (1630 ± 181 ft. lbs.)
torque.
FIGURE 2-8. REAR WHEEL MOUNTING

1. Outboard Tire and Rim 3. Clamp Nut
2. Clamp Nut 4. Inboard Tire and Rim

TIRE MATCHING
The matching of tires on drive axle dual wheel installa- Exact limitations are not specified by tire manufactur-
tions is important in order to achieve satisfactory life, ers, but a general rule is:
both of the tires and of the load carrying components
Unloaded, inflated tires, when standing side by
of the final drive.
side, should not exceed a 1% maximum variation
To check matching of duals already mounted on the in their diameters.
truck, use a large square. If one tire is too small, it
Measuring of tire size is most accurate when the tire is
becomes obvious as the square is laid across the dual
mounted on a wheel, inflated to correct pressure, and
tires. The square can be made from two 1 in. x 2 in.
totally unloaded (off the truck, or off the ground, if
wood strips (one piece long enough to span the dual
mounted on a truck). Use a steel tape placed in the
tires). The two wood strips should be squared with a
center of the tread and measure the total circumfer-
carpenter’s square and rigidly fastened to maintain a
ence of the tire. Using the formula below, calculate the
true 90o angle.
diameter, "d".
Matching of tire diameters from one side of an axle to
diameter "d" = measured circumference ÷ 3.1416
the opposite side is important to prevent unstable load
diameter "d" x 0.01 = Allowable Variation in size
shifting, excess load on structural members, and rapid
wear of the internal components of the final drive.
Side by side matching on dual wheel installations is The tires used on opposite sides of HAULPAK® Trucks
necessary to prevent excess loading on the tire having should also be limited to a 1% variation in diameter of
the larger diameter. Mismatched tires on the duals the inflated, unloaded tires.
cause unequal distribution of the load. Rapid wear
and/or tire blowout can result.

FRONT WHEEL HUB AND SPINDLES
FRONT WHEEL HUB
Removal
Each Brake Caliper weighs approximately 70 kg.

1. Block the rear wheels on both the front and rear (154 lbs.)
sides. The Wheel Hub Assembly weighs approximately
568 kg (1252 lbs.).
Use adequate lifting devices when lifting these
2. Refer to Front Tire and Rim Removal, this Section, components.
and remove front tire and rim assembly.
4. Refer to Front Brake Caliper Removal, Section "J"
and remove the front caliper assembly.
3. Disconnect and cap brake lines at brake calipers
(10).
5. Remove wheel cover (1, Figure 3-1).
6. Support or lift wheel hub with an adequate lifting

device.
FIGURE 3-2. FRONT HUB
1. Spindle 2. Front Hub

FIGURE 3-1. FRONT WHEEL HUB
1. Cover 3. Wheel Hub

2. Retainer 4. Spacer
G03011 12/91 Front Wheel Hub and Spindle G3-1

7. Remove capscrews (3, Figure 3-3) retainer (2). DISASSEMBLY OF FRONT WHEEL HUB
ASSEMBLY
1. Remove brake disc capscrews and brake disc (3,

Figure 3-5) if necessary.
2. Remove oil seal (1) and outer race (2).
3. Remove outer race (4).
FIGURE 3-3. FRONT WHEEL COVER

1. Cover 3. Capscrew
2. Retainer
8. Check the number and thickness of the shims

behind retainer and keep in a safe place. FIGURE 3-5. WHEEL HUB
1. Oil Seal 3. Brake Disk

9. Rock wheel hub assembly (2, Figure 3-4) lightly 2. Outer Race 4. Outer Race
from the rear, and push out together with bearing
(1).
4. Remove bearing (1, Figure 3-6) and spacer (2).
5. Clean all metal parts in cleaning solvent.
10. Remove bearing (1), then remove wheel hub as-
sembly (2).
FIGURE 3-4. WHEEL HUB AND BEARINGS

FIGURE 3-6. WHEEL BEARING
1. Outer Bearing 2. Hub Assembly
1. Bearing 3. O-Ring
2. Spacer
G3-2 Front Wheel Hub and Spindle G03011 12/91

Inspection
1. Inspect all seals and bearings and replace as
required.
2. Check seal ring mounting area on wheel hub,
brake adaptor and spindle for damage that could
cause leakage.
3. Inspect spindle in area of bearing surfaces and
radius under spacer for distress or cracks. Non-
destructive methods of crack detection (dye
penetrant or magnaflux) should be used.
FIGURE 3-7. FRONT WHEEL BEARING
ASSEMBLY OF FRONT WHEEL HUB ASSEMBLY 1. Cover 2. Grease Cavity
1. Clean all metal parts in cleaning solvent.

2. Install O-Ring (3, Figure 3-6), spacer (2) and bear- Front Wheel Hub Bearing Adjustment
ing (1). 1. Install retainer (1, Figure 3-8) with 3 mounting
3. Using a push tool, press outer races (2 and 4, capscrews without installing any shims. Rotate
Figure 3-5) into hub. hub 20-30 times and tighten capscrews uniformly
to 13.0 ± 0.5 kg.m (94 ± 4 ft. lbs.) torque.
4. Using a push tool, press fit oil seal (1) into hub.
2. Measure dimension (A) from retainer to tip surface
5. Set brake disc (3) in position on hub. Apply thread of axle with depth micrometer (2).
tightener Three Bond (TB1374) to the capscrews
and attach brake disc to hub. Tighten capscrews NOTE: When removing the retainer, be careful that the
to 94.5 ± 10 kg.m (685 ± 72 ft. lbs.) torque. bearing does not come out.
6. Support or lift wheel hub with an adequate lifting NOTE: Measure two places on retainer and take the
device and install on spindle. average.
7. Fill the shaded portion (Figure 3-7) fully with 3. Remove retainer (1), and measure retainer thick-
grease shown in Table 1. Approximately 17.5 liters ness C. Then select shim thickness equal to B
(4.6 gallons) of grease is required for each wheel. (B= A-C) + 0.3mm (0.012 in).
NOTE: Be careful not damage the oil seal on the inside NOTE: Select the combination of shims that gives the
of the hub. minimum number of shims.
8. Install bearing (1, Figure 3-4).
TABLE 1. WHEEL BEARING GREASE
MANUFACTURER BRAND NAME

Mobil Oil Mobil Grease HP-2
Showa Shell Oil Super Duty Grease 2
Esso Oil Ronex MP
FIGURE 3-8. PRELOAD ADJUSTMENT
1. Retainer 2. Depth Micrometer

4. Apply thread tightener Three Bond (TB1374) to the Installation
capscrews and install shims and retainer (1). Ro-
1. Install new O-Rings (5, Figure 3-9) in bearing (6).
tate hub 20-30 times and tighten capscrews uni-
formly to 94.5 ± 10 kg.m (685 ± 72 ft. lbs.) 2. Position A-Frame to frame and install spacers (3)
torque. and pins (7) with retaining capscrews. Tighten
capscrews to standard torque.
NOTE: After tightening the bolts, rotate the hub and
check that there is no abnormality in rotation. 3. Refer to Section "H", "Front Suspension Installa-
tion" and install the front suspension.
4. Refer to section "G", "Front Tire and Rim Installa-
5. Fill the inside of the cover (shaded portion, Figure
tion" and install the front tires.
3-7) with grease as shown in Table 1.
6. Fit O-ring in cover (1, Figure 3-3) and install cover.
7. Refer to Section "J" Installation of Front Brake
Caliper and install front brake caliper.
8. Connect brake lines to calipers.
Bleed brakes before placing truck in production.

Refer to Brake Bleeding, Section "J".
FRONT WHEEL SPINDLE REMOVAL

AND INSTALLATION
The spindle is part of the front suspension cylinder. To
remove or install the spindle, refer to Section "H",
Suspensions.
SUSPENSION A-FRAME
Both A-Frame mounting pins are the same.
Removal
FIGURE 3-9. A-ARM PIN
1. Refer to section "G", "Front Tire and Rim Removal"
and remove front tires. 1. Bushing 5. O-Ring
2. Refer to Section "H", "Front Suspension Removal" 2. Frame 6. Bearing
and remove the front suspension. 3. Spacer 7. Pin
4. Snap Ring\ Seal
3. Use a suitable lifting device and support the A-
Frame. Remove retaining capscrew and pin (7,
Figure 3-9) and spacers (3).
4. Remove A-Frame from frame.

CENTER TIE ROD PIVOT
1. Remove capscrews and washers (9, Figure 3-10) 1. Press in bushings (4, 6, and 11).
and the grease lines connected to pins (3 and 10). 2. Place pivot link in frame with O-Rings (5) and install
2. Slide tie rod (13) away from pivot link (7). pin (3). Install washer (1) and snap ring (2).
3. Remove snap ring (2), washer (1) and pivot pin (3). 3. Install ball joint assembly (16), O-Rings (15), and
snap ring (14) in pivot link.
4. Remove pivot link.
4. Install seals (12).
5. Remove seals (12), snap rings (14) and push out
ball joint assembly (16). 5. Position tie rod in pivot link and install pin (10).
Install retaining capscrew and washer (9).
6. Connect grease lines to pins and lubricate all
Inspection joints.
1. Inspect all bushings (4, 6, and 11) for wear.
2. Inspect all seals (12) and O-Rings (5, and 15).
3. Replace any worn or damaged parts.
FIGURE 3-10. CENTER TIE ROD PIVOT
1. Washer 5. O-Ring 9. Capscrew and 13. Tie Rod

2. Snap Ring 6. Bushing washer 14. Snap Ring
3. Pivot Pin 7. Pivot Link 10. Tie Rod Pin 15. O-Ring
4. Bushing 8. Spacer 11. Bushing 16. Ball Joint
12. Seal

NOTES

FINAL DRIVE ATTACHMENTS
FINAL DRIVE ANCHOR
4. Place jack under the rear suspension lower link

Lower Link
mount to be removed.
Removal
1. Securely block front and rear wheels.
2. Support rear of frame from the floor under the hoist
cylinder mounting. Be sure jack is secure to lower mount so it will not
3. Support front and rear side of rear axle housing. slide off as jack is extended.
5. Block final drive securely in this position.
6. Remove pin retaining capscrew and remove pin
(4, Figure 4-1).
7. Remove spacers (3, Figure 4-2) and O-Rings (5).
Remove only one link at a time. If more than one 8. Remove snap ring (4) and bearing (6).
link is to be removed at the same time, extra
supports must be in place to prevent the frame and
axle from moving out of position.
FIGURE 4-2. LOWER LINK PIN

1. Bushing 5. O-Ring
2. Frame 6. Bearing
FIGURE 4-1. REAR AXLE 3. Spacer 7. Pin
1. Pin 3. Link 4. Snap Ring\ Seal
2. Diagonal Link 4. Pin
G04008 Final Drive Attachments G4-1

DIAGONAL PANHARD ROD
Inspection Removal
1. Clean all parts. 1. Park truck on level surface and securely block
2. Inspect pin for wear, galling and cracks. wheels.
3. Inspect bearing for wear and freedom of move- 2. Securely support frame on each side under lower
ment. hoist cylinder mounts. Support frame so there is
not any weight being applied to the rear axle.
4. Inspect dirt seal for cracks or damage that could
allow dirt to enter. 3. Support panhard rod (1, Figure 4-4).
5. Replace any damaged or worn components found 4. Remove retainer capscrews from panhard rod
during inspection. pins (7).
5. Remove panhard rod pins and panhard rod from
Installation frame and final drive case.
1. Install one snap ring (4) and press bearing (6) in 6. Remove spacers (6, Figure 4-4) and O-Rings (2).
link until it contacts snap ring. Install second snap
ring. 7. Remove snap rings (7) and bearing (1).
NOTE: Install snap rings as shown in Figure 4-3.

2. Install new O-Rings (5) in bearings (6).
3. Install spacers (3, Figure 4-2).
4. Install pin (7) and retaining capscrew. Tighten to
standard torque.
5. Raise rear of frame and remove support from
under lower hoist cylinder mounts.
FIGURE 4-4. DIAGONAL PANHARD ROD

1. Bearing 5. Pin
FIGURE 4-3. SNAP RING ORIENTATION
2. O-Ring 6. Spacer
1. Link 2. Snap Ring 3. Panhard Rod 7. Snap Ring
4. Bushing
G4-2 Final Drive Attachments G04008

Inspection 2. Install new O-Rings (2, Figure 4-4) in bearings (1).
1. Clean all parts. 3. Install spacers (6).
2. Inspect pin for wear, galling and cracks.
3. Inspect bearing for wear and freedom of move-
ment.
4. Inspect dirt seal for cracks or damage that could
allow dirt to enter.
When installing panhard rod, misalignment of sec-
5. Replace any damaged or worn components found
ond pin and bearing will probably occur. Raise or
during inspection.
lower frame with jacks or adequate lifting device
ON EACH SIDE OF FRAME.
Installation
DO NOT use rear suspensions, because there is no
1. Install one snap ring (7) and press bearing (1) in restraint to keep frame from shifting to one side or
link until it contacts snap ring. Install second snap the other.
ring.
NOTE: Install snap rings as shown in Figure 4-3. 4. Place panhard in position and install pin (5) and
retaining capscrew. Tighten to standard torque.
5. Install grease lines.
G04008 Final Drive Attachments G4-3

NOTES
G4-4 Final Drive Attachments G04008

FINAL DRIVE CENTER CASE ASSEMBLY
The differential unit is designed to transmit the rotary In order to adjust the bearings and gear backlash,
power from the propeller shaft to the left and right shims are used at the pinion end and adjusting nuts are
wheels. It consists of a reduction unit and a differential used at the bevel gear end.
unit which provides a difference in rotational speed to
the left and right wheels when negotiating curves.
Specifications:
Because of its structure, the differential bearing is sub- Splash-Type Lubrication
ject to force in the thrust direction and radial direction.
Ratio: 3.467
For this reason, a taper roller bearing is used.
Oil: EO30-CD, 130l (34 gal)
FIGURE 5-1. DIFFERENTIAL

1. Coupling 5. Nut 10. Differential Case
2. Park Brake Support 6. Cap 11. Side Gear (24 Teeth)
3. Bearing Carrier 7. Differential Gear Case 12. Pinion Gear (20 Teeth)
4. Case 8. Cross Shaft 13. Bevel Pinion (15 Teeth)
9. Bevel Gear (52 Teeth) 14. Shims
G05010 5/95 Final Drive Center Case Assembly G5-1

OPERATION
Straight-away-travel-
Power from the pinion passes through the bevel gears In this case, bevel and side gears rotate at the same
to turn the differential case. The differential pinion trans- speeds so the case and the shaft turn as a single unit.
fers this rotation to the differential side gears where it
turns the drive shafts splined to the gears. During
straight-away travel, the resistance on the tires is equal,
same resistance on both left and right drive shafts, so
the differential pinions do not turn. Instead, the rotation
of the case is transferred directly to the side gears.
FIGURE 5-2. FINAL DRIVE HOUSING
1. Parking Brake 3. Axle Housing 5. Final Drive

2. Differential 4. Brakes 6. Fill Plug
G5-2 Final Drive Center Case Assembly G05010 5/95

Turning REAR AXLE
In a turn, the resistance on the inside tire is greater than
on the outside one so the resistances on the drive shaft Removal
are not balanced. Consequently, the side gears then
rotate at different speeds. The differential pinions;
therefore, rotate as they transmit the rotation of the
case to the side gears. This rotation forces the two side
Make sure jacks, lifting equipment and rigging
gears to rotate in opposite directions. The net effect is
have adequate capacity and are securely attached
that the outside wheel turns at a rate equal to the sum
to raise and hold rear of truck until blocking or
of the bevel gear speed and the differential pinion
support stands are securely installed. Total weight
speed, while the inside one turns at a rate equal to the
of rear end of truck (without body liners) is approxi-
difference.
mately 32 914 kgs. (72,563 lbs). Weight of final
drive assembly with tires is approximately
15 875 kgs (35,000 lbs.).
To Check Oil Level
Remove plug (6, Figure 5-2) and check the oil level. If
1. Park truck on level surface.
the oil level is not at or near the lower end of the plug
hole, refill through the plug hole. 2. Securely block front wheels.
3. With engine running, release parking brake and
disconnect linkage. Refer to Section "J", Parking
Brake Removal for instructions for disconnecting
parking brake linkage. Shut down engine.
Specifications:
4. Raise rear of frame high enough to clear final drive
Reduction Ratio:
case as it is rolled from under truck.
Differential: 3.467
Final Drive: 6.500
Total: 22.54
Oil
Differential: EO30-CD, 130l (34.4 gal)
Final Drive: EO30-CD, 64 l (17 gal) each side
Tire size: 24.00-49 or 27.00-49
Rim size: 17.00-49 or 19.50-49
FIGURE 5-3. REAR AXLE MOUNTING

1. Pin 3. Link
2. Diagonal Link 4. Pin

5. Securely block under lower hoist cylinder mount Installation
structure of frame.
6. Block rear wheels to prevent final drive assembly
from moving.
7. Remove drive line between final drive and trans- Make sure jacks, lifting equipment and rigging
mission. Slide drive line out of protector and set have adequate capacity and are securely attached
aside. to raise and hold rear of truck until blocking or
support stands are securely installed. Total weight
8. Disconnect all hydraulic lines to wet disc brake
of rear end of truck (without body liners) is approxi-
assemblies. Cap/plug all ports and hoses to pre-
mately 32 914 kg (72,563 lbs.). Weight of final drive
vent dirt entry.
assembly with tires is approximately 15,890 kg
9. Remove rock ejectors from both sides of body. (35,000 lbs.).
10. Completely vent nitrogen from both rear suspen-
sions. Refer to Section "H", Oiling and Charging 1. Align final drive assembly to frame.
Procedures.
2. Roll final drive under frame and block wheels.
11. Attach lifting device to a rear suspension. Refer to
3. Refer to Final Drive Attachment, this Section, for
Section "H", Rear Suspension Removal. Remove
Lower Link Installation. Install Lower Link.
both suspensions.
4. Raise panhard rod to connect to frame. Refer to
12. Refer to Final Drive Attachment, this Section, for
Final Drive Attachment, this Section, for Panhard
Lower Link and Panhard Rod Removal. Remove
Rod Installation. Install Panhard Rod.
these components.
5. Attach lifting device to a rear suspension. Refer to
13. Remove any electrical wiring, air lines or lube lines
Section "H", Rear Suspension Installation. Install
that may interfere with removal of the final drive
both suspensions.
assembly.
6. Install drive line with slip joint end toward transmis-
14. Remove blocks from behind rear wheels.
sion. Tighten companion flange capscrews to 18
15. While supporting anchor structure, roll final drive ± 2 kg.m(130 ± 15 ft.lbs.) torque.
out from under frame.
7. Install all hydraulic lines to rear brake assemblies
and connect electrical ground strap at anchor pin.
Before placing truck in production, brakes must be

bled. Refer to Section "J" for Brake Bleeding pro-
cedure.
8. Install rock ejectors on both sides of body.

9. Raise rear of frame and remove blocks or support
stands from under lower hoist cylinder mount
structure.
10. Start engine, release parking brake, install linkage
from park brake actuator to park brake lever. Refer
to Section "J", Parking Brake Installation for in-
structions for connecting parking brake linkage.
Apply park brake, shut down engine.
11. Charge all suspensions. Refer to Section "H", Sus-
pension Oiling and Charging Procedure.

DIFFERENTIAL ASSEMBLY
Removal
1. Drain 132 l (35 gal) of oil from the differential gear
case and 64 l (17 gal) of oil from each final drive
gear case.
2. Refer to "Parking Brake Spring Cylinder Removal",
Section "J", and remove parking brake spring
cylinder.
3. Refer to "Slack Adjuster Removal", Section "J", and
remove slack adjuster assembly.

1. Guard 3. Drive Shaft
2. Cover
8. Remove guard (1, Figure 5-6) and cover (2).

9. Remove drive shaft assembly (3).
Make sure lifting equipment is of adequate capac-

ity to handle 1500 kg (3307 lbs).
FIGURE 5-4. BRAKE LINES AND BRACKET
10. Install a shackle to the differential mounting sur-
1. Brake Lines 3. Bracket
face, then fit a lever block to the pinion end, and
2. Brake Lines
adjust the height when removing.
4. Remove hoses (1 & 2, Figure 5-4). NOTE: Be careful not to damage the seal surface of
5. Remove bracket (3). Loosen the U-capscrews, the housing.
turn over the valve assembly bracket and set it on 11. Remove differential assembly (2, Figure 5-7).
top of the cross-member.
7. Install an eyebolt and remove shaft (2) with a bar.
FIGURE 5-7. DIFFERENTIAL ASSEMBLY

FIGURE 5-5. COVER AND SHAFT 2. Differential
1. Lift Chain
1. Cover 2. Shaft Assembly

Installation DIFFERENTIAL ASSEMBLY
Disassembly
1. Set differential assembly in tool (2, Figure 5-8).
Make sure lifting equipment is of adequate capac- Tool (2) consists of repair stand 790-501-2000 and
ity to handle 1500 kg (3307 lbs). bracket 790-901-5110.
2. Pump air into park brake spring cylinder to retract
NOTE: Be careful not to damage the seal surface of rod, then pull out connecting pin (3) of slack
the housing. adjuster lever (4), and remove spring cylinder (1).
1. Install a shackle to the differential mounting sur-

face, then fit a lever block to the pinion end, and
adjust the height when installing differential as-
sembly (2, Figure 5-7). Apply Three Bond # 1374
thread tightener to mounting capscrews and If the air in the spring cylinder is released, the rod
tighten to 94.5 ± 10 kg.m (684 ± 72 ft.lbs.) will suddenly extend, so be careful not to get
torque. caught.
2. Apply Three Bond # 1374 thread tightener to cap-
screws and install drive shaft assembly (3, Figure
5-6). Tighten capscrews to 18 ± 2 kg.m (130 ± 14
ft.lbs.) torque.
3. Install guard (1) and cover (2).
4. Install shaft (2, Figure 5-5) with a bar and remove
eyebolt.
5. Install cover (1).
6. Install bracket (3, Figure 5-4).
7. Install hoses (1 & 2).
8. Refer to "Slack Adjuster Installation", Section "J", FIGURE 5-8. PARK BRAKE SPRING CYLINDER
and install slack adjuster assembly.
1. Spring Cylinder 3. Connecting Pin
9. Refer to "Parking Brake Spring Cylinder Installa-
2. Tool 4. Lever
tion", Section "J", and install parking brake spring
cylinder.
10. Add 132 l (35 gal) of oil to the differential gear case 3. Caliper assembly
and 64 l (17 gal) of oil to each the final drive gear
case. Refer to "Lubrication and Service", Section a. Remove plate (1, Figure 5-9) on one side, then
"P", for oil specifications. Check differential and remove caliper (3) together with pad (2).
each final drive for proper oil level. b. Remove plate on other side.
c. Remove brake disc (1, Figure 5-10).

FIGURE 5-9. CALIPER
1. Plate 3. Caliper
2. Pad
FIGURE 5-11. PINION AND CARRIER
1. Lifting Device 2. Carrier Assembly
4. Remove retaining capscrew (3, Figure 5-10), and
mounting capscrews (6), then remove coupling
(2) together with holder (4) and O-ring.
Disassembly of Pinion Carrier Assembly
5. Remove support (5).
1. Remove carrier (2, Figure 5-12) together with inner
6. Install coupling and lifting device (1, Figure 5-11) bearing (3) from pinion gear (1).
and screw in pusher bolts, then lift off pinion and
carrier assembly (2). 2. Remove spacer (5), then remove inner bearing (4).
NOTE: Check the number and thickness of the
shims, and keep together in a safe place for instal-
lation at re-assembly of pinion and carrier.
FIGURE 5-10. BRAKE COUPLING FIGURE 5-12. PINION BEARING

1. Brake Disc 4. Holder 3. Inner Bearing
1. Pinion Gear
2. Coupling 5. Support 4. Inner Bearing
2. Carrier
3. Capscrew 6. Capscrews 5. Spacer

FIGURE 5-13. PINION GEAR AND RACES FIGURE 5-15. DIFFERENTIAL MOUNTING
1. Outer Race 4. Holder 1. Cap 3. Adjustment Nuts
2. Outer Race 5. Inner Race 2. Capscrews 4. Gear Assembly
3. Carrier 6. Pinion Gear
3. Remove holder (4, Figure 5-13), then remove 3. Loosen mounting capscrews (2, Figure 5-15), and
center bearing inner race (5) from pinion gear (6). remove cap (1).
4. Remove bearing outer races (2) and (1) from 4. Lift off differential gear assembly (4).
carrier (3).
5. Remove left and right side bearing adjustment nuts
NOTE: The bearing is an adjustment-free bearing (3).
assembly (2 tapered roller bearings and spacer),
so check the matching numbers, and keep as a set
in a safe place.
Disassembly Of Differential Gear Unit
Differential Gear Unit
1. Remove lock (1, Figure 5-14). 1. Using puller (1, Figure 5-16) remove bearing (2).
2. Using wrench 790-425-1660 (2), loosen left and
right side bearing adjustment nuts (3) until they
can be turned by hand.
FIGURE 5-16. BEARING PULLER

FIGURE 5-14. DIFFERENTIAL
1. Locks 2. Wrench 1. Puller 2. Bearing
3. Nuts

FIGURE 5-17. DIFFERENTIAL CASE
1. Case 2. Capscrews
FIGURE 5-20. PINION GEAR ASSEMBLY

1. Gear Assembly 2. Cross Shaft
2. Remove mounting capscrews (2, Figure 5-17),

then remove case (1).
3. Remove thrust washer (1, Figure 5-18) from case
(2).
4. Remove side gear (1, Figure 5-19).
5. Remove pinion gear assembly (1, Figure 5-20)
together with cross shaft (2).
FIGURE 5-18. THRUST WASHER 6. Hold pinion gear assembly (3, Figure 5-21) with
press, and using wrench 09003-07280 (1), remove
1. Thrust Washer 2. Case
ring nut (2).
FIGURE 5-19. SIDE GEAR FIGURE 5-21. RING NUT AND GEAR
1. Side Gear 2. Gear 1. Wrench 3. Pinion Gear

2. Ring Nut

7. Pull out shaft (4, Figure 5-22) with press, then
remove pinion gear, bearing (1), and collar (3).
8. Remove bearing (2) from shaft (4).
9. Remove bearing outer races (1, Figure 5-23) and
(2) from pinion gear.
NOTE: The bearing is an adjustment-free bearing, so
check the matching numbers of the bearing, collar,
and outer race, an keep together as a set in a safe
place.
10. Remove side gear (1, Figure 5-24).

11. Remove thrust washer (1, Figure 5-25).
12. Remove bevel gear (3, Figure 5-26) from case (2).
FIGURE 5-22. GEAR AND SHAFT 13. Remove bearing (1) from case (2)
1. Bearing 3. Collar 14. Remove snap ring (2, Figure 5-27), then remove
2. Bearing 4. Shaft bearing (1) from differential case (3).
FIGURE 5-23. GEAR BEARINGS

1. Outer Races 2. Outer Races FIGURE 5-25. BEVEL GEAR
1. Thrust Washer 2. Bevel Gear
FIGURE 5-24. FIGURE 5-26. DIFFERENTIAL BEARING

1. Side Gear 2. Bevel Gear 1. Bearing 3. Bevel Gear
2. Case

FIGURE 5-28. BEARING INSTALLATION
1. Bearing 2. Shaft
FIGURE 5-27. DIFFERENTIAL BEARING
1. Bearing 3. Differential Case
2. Snap Ring
5. Differential Pinion Side Gear.

ASSEMBLY of DIFFERENTIAL NOTE: The bearing is an adjustment-free bearing as-
sembly, so check the numbers on the bearings, collar,
Differential Bearing and outer races, and use only as a matching set.
1. Set differential case in tool (2, Figure 5-8). Tool (2)
consists of repair stand 790-501-2000 and bracket a. Using push tool, press fit outer races (1 & 2,
790-901-5110. Figure 5-23) in pinion gear.
2. Using a push tool, press fit bearing (1, Figure 5-27) b. Using push tool, press fit bearing (1, Figure
in differential case (3), then install snap ring (2). 5-28) to shaft (2).
c. Set pinion gear to shaft, then assemble collar
Assembly Of Differential Gear Assembly (3, Figure 5-22), and using push tool, install
bearing (1).
1. Install bevel gear (3, Figure 5-26) in differential gear
case (2). Apply Three Bond # 1374 thread tight- d. Apply Three Bond thread tightener # 1374 to
ener to mounting capscrew and tighten to 94.5 ring nut (2, Figure 5-21). Hold pinion gear as-
kg.m (684 ft.lbs.) torque. sembly (3) with press, and using wrench 09003-
07280 (1), tighten ring nut (2).
2. Install side bearing (1). Shrink fit bearing by heat-
ing to 100° C (212° F). 6. Assemble pinion gear assembly (1, Figure 5-20) to
cross shaft (2), then raise and install to case.
NOTE: Bearings should be heated by heat lamps, oil
bath, or induction heaters. Do not use a torch or heat NOTE: Align the notched portion of the pinion gear
greater than 176° C (350° F). shaft with the dowel pin of the case, and install.
NOTE: After bearing cools, check that there is no

clearance between the end face of the case and NOTE: Move the pinion gear, and check that the gear
the bearing. assembly rotates easily.
3. Turn case over, then align with dowel pin, and 7. Install side gear (1, Figure 5-19).
install thrust washer (1, Figure 5-25). 8. Align with dowel pin, and install thrust washer (1,
NOTE: Check that the head of the dowel pin is 0.5 + 0.2 Figure 5-18).
-0.0 mm (0.02 + 0.0078 - 0.0 in) lower than the surface NOTE: Check that the head of the dowel pin is 0.5 + 0.2
of the washer. -0.0 mm (0.02 + 0.0078 - 0.0 in) lower than the surface
4. Install side gear (1, Figure 5-24). of the washer.

Installation Of Differential Assembly
1. Tighten side bearing adjustment nuts (3, Figure
5-15) temporarily, and place differential gear case
assembly (4) temporarily.
2. Align match marks and fit cap (1) to assembly.
Rotate the bevel gear 20 - 30 turns to settle the
bearings, then tighten. Apply Three Bond thread
tightener # 1374 to mounting capscrews (2) and
tighten to 175 kg.m (1266 ft.lbs.) torque.
3. Adjusting preload of bearing
a. Install measurement adapters 790-425-1670 (2,
Figure 5-31) to both ends of cap.
b. Measure dimension between adapters with
FIGURE 5-29. BEARING INSTALLATION depth micrometer 792-525-3000 (1).
1. Side Bearing 2. Case
9. Heat side bearing (1, Figure 5-29) to 100° C (212°

F) and install to case (2).
bath, or induction heaters. Do not use a torch or heat
greater than 176° C (350° F).
NOTE: Check that there is no clearance between

the end face of the case and the bearing.
FIGURE 5-31. BEARING PRELOAD

10. Fit case (1, Figure 5-30) to housing. Apply Three
Bond thread tightener # 1374 to mounting cap- 1. Micrometer 2. Adapter
screws (2) and tighten to 94.5 kg.m (684 ft.lbs.) 792-525-3000 790-425-1670
torque.
NOTE: When measuring, hold the micrometer securely
with one hand, and put the probe in contact parallel to
the measurement adapter.
c. Add 0.4 ± 0.15 mm (0.016 ± 0.006 in) to the

measured dimension, and set scale of mi-
crometer.
NOTE: The added dimension becomes the amount of
deflection of the case before applying preload and
after applying preload.
d. Tighten adjustment nuts (3, Figure 5-14) from

both ends, and continue to tighten with wrench
790-425-1660 (2), paying careful attention to
the groove that the lock enters.
NOTE: To settle the bearing properly when doing this,
FIGURE 5-30. CASE INSTALLATION rotate the bevel gear and tap the bearing cap and bevel
gear with a soft-faced hammer,
1. Case 2. Capscrews

NOTE: Precautions when adjusting preload. Input Pinion and Carrier Assembly
If the increase in deflection caused by overtightening When assembling the differential pinion carrier assem-
of the adjustment nut exceeds the standard amount, bly (Figure 5-33), if coupling bolts are not tightened
return the adjustment nuts to the condition before while the pinion bearing is turning, the bearing will be
adjusting. When doing this, rotate the bevel gear and damaged in a short period of operation.
tap the bearing cap and bevel gear with a plastic
To prevent such trouble, this assembly procedure must
hammer, check that there is no clearance at portion
be followed.
(A), and adjust again.
1. Using push tool, press fit outer races (1, Figure
5-34) and (2) in cage (3). Check that there is no
Use a light with a feeler gauge to clearance between the outer races and the carrier.
check that there is no gap.
No Gap
FIGURE 5-32. BEARING ADJUSTMENT

FIGURE 5-34.
1. Outer Race 3. Carrier
2. Outer Race
2. Heat bearing inner race (2, Figure 5-35) to 100°C

(212°F), then press center bearing inner race onto
pinion gear (3), then install holder (1). Apply
Three Bond thread tightener # 1374 to mounting
bolts and tighten to 11.5 ± 1 kgm (83 ± 8 ft.lbs.)
torque.
bath, or induction heaters. Do not use a torch or heat
greater than 176° C (350° F).
FIGURE 5-33. INPUT PINION ASSEMBLY

1. Capscrew & Washer 10. O-Ring
2. Park Brake Disc 11. Capscrew & Washer
3. Coupling 12. Holder
4. Capscrew & Washer 13. Bearing Race
5. Holder 14. Pinion Gear (15 T)
6. O-Ring 15. Bearing Carrier FIGURE 5-35.
7. Park Brake Support 16. Shim Assembly
17. Capscrew & Washer 1. Holder 3. Pinion Gear
8. Oil Seal
18. Bearing Assembly 2. Bearing Inner Race
9. O-Ring

3. Heat bearing inner race* (1, Figure 5-36) to 100°C 6. Fit O-ring (10, Figure 5-33) onto bearing carrier
(212°F), then press onto pinion gear shaft and (15), and assemble shims* (16, Figure 5-33), then
install spacer (2). install pinion and cage assembly (1, Figure 5-38)
to differential case.
* The bearing is an adjustment-free bearing, so
* NOTE: Use the same amount of shims that
check the matching numbers, and keep them
were removed at time of pinion disassembly.
together as a set.
If any parts, such as bearings, bearing carrier,
* Check that there is no clearance between the pinion gear, or housing have been replaced, be
end face of the pinion gear and the inner race. certain to refer to "Adjusting Tooth Contact,
Backlash" later in this procedure to determine
the correct shim thickness.
FIGURE 5-36.
1. Bearing Inner Race 2. Spacer
FIGURE 5-38.
1. Cage Assembly
7. Install oil seal (3, Figure 5-39) and O-ring (2) to park
brake support (1). Install support (1) to differential
4. Set carrier (2, Figure 5-37) to pinion gear (3), and
case. Apply Three Bond thread tightener # 1374
install bearing (1).
to mounting bolts and tighten to 56 ± 6 kgm (405
± 45 ft.lbs) torque.
FIGURE 5-37. FIGURE 5-39.

1. Bearing 3. Pinion Gear 1. Park Brake Support 3. Oil Seal
2. Carrier 2. O-ring
5. Coat the bearing rollers as well as the running

surfaces of the inner and outer races thoroughly
with E030-CD.

8. Fit coupling (4, Figure 5-40), O-ring and holder (2), * 2) Measure the axial bearing end play for:
and apply Three Bond thread tightener # 1374 to 0.01 - 0.17 mm (0.0004 - 0.0067 in.)
mounting bolt (3). Tighten bolt* (3) gradually to Measuring method:
225 ± 25 kgm (1627 ± 180 ft.lbs) torque while the i) After the bearing has been run 20 to 30 rota-
bearing is turning (20 to 30 rotations). tions, set a dial gauge as shown in Figure
* If the bolt (3) is tightened without keeping the 5-42 to align with Point Zero.
bearing turning, there will be a possibility of dam-
aging the bearing .
FIGURE 5-42.
FIGURE 5-40.
ii) Oscillate the coupling 20 to 30 rotations in its
1. Park Brake Support 3. Bolt lifted condition (approximately 300 kg) and
2. O-ring and Holder 4. Coupling make sure that the dial gauge reading has
been stabilized. (See Figure 5-43)
9. After tightening bolt (3), turn the bearing 20 to 30
rotations again, and make sure that the bearing is
running smoothly and that bolt (3) has been tight-
ened to the specified torque.
10. Using either of the following methods* , confirm that
the bearing has been set normally.
* 1) Measure the starting torque in the tangential
direction with a spring scale (1, Figure 5-41)
attached to a threaded hole in the coupling (396
mm [15.6 in.] bolt circle dia.). Starting torque
must not be greater than 5.1 kg. (11.2 lbs.) FIGURE 5-43.
maximum.
Perform this measurement on the bevel gear
side.
iii) The dial gauge reading obtained in ii) above
will be equal to the end play in the axial
direction.
FIGURE 5-41.
1. Spring Scale

Adjusting Tooth Contact, Backlash
Adjust backlash and tooth contact at the same time. 2. Adjust tooth contact as follows.
1. Adjust backlash as follows. a Adjust the in and out movement of the bevel
pinion by changing the shims between the dif-
a. Move bevel gear with adjustment nuts (1 & 2,
ferential case and bearing cage.
Figure 5-44).
b. Adjust tooth contact in Step 3.
NOTE: When adjusting the bevel gear, do not change
the preload of the bearing. Always turn the adjustment
nuts at both ends the same amount in the same direc-
tion.
b. Put a dial Indicator (2, Figure 5-45) at right

angles in contact with the reverse face of the
tooth at the outside of the bevel gear. Turn the
adjustment nut and adjust the backlash.
c. Backlash: Adjust at 3 - 4 places. Keep the pinion
gear locked when measuring. Adjust to 0.41-
0.56 mm (0.016 - 0.022 in) backlash.
FIGURE 5-45. TOOTH CONTACT ADJUSTMENT

FIGURE 5-44. BACKLASH ADJUSTMENT
1. Adjustment Nut 2. Adjustment Nut
1. Bevel Gear 2. Dial Indicator

3. Adjusting tooth contact
Mix red lead (minium) in spindle oil, then coat the Adjust the tooth contact as shown in the following
face of 7 or 8 teeth of the driven gear. Hold down illustrations and procedure.
the driven gear by hand to act as a brake, and
rotate the drive pinion gear forward and back-
ward, then inspect the pattern left on the teeth.
Tooth contact Cause Procedure for adjustment
The tooth contact pattern Adjust the drive pinion by adjusting the shims at the
should start from about 5 mm drive pinion cage. Adjust the driven gear in the same
from the toe of the bevel gear way as when adjusting backlash.
and cover about 50% of the
length of the tooth. It should be
in the center of the tooth height.
1. Reduce shims at drive pinion

Drive pinion is too far from to bring closer to driven
driven gear. gear.
2. Move driven gear further
away from drive pinion and
adjust backlash correctly.
1. Increase shims at drive pin-

ion t o move away from
Drive pinion is too close to driven gear.
driven gear.
2. Move driven gear closer to
drive pinion and adjust back-
lash correctly.
1. Reduce shims at drive pinion

to bring closer to driven
gear.
Driven gear is too close to
drive pinion. 2. Move driven gear further
away from drive pinion and
adjust backlash correctly.
1. Increase shims at drive pin-

ion t o move away from
Driven gear is too far from driven gear.
drive pinion.
2. Move driven gear closer to
drive pinion and adjust back-
lash correctly.

4. Caliper assembly 9. Install spring cylinder assembly (1, Figure 5-48),
a. Install brake disc (1, Figure 5-46). Apply Three and connect rod clevis with connecting pin (3) to
Bond thread tightener # 1374 to disc plate cap- lever of slack adjuster (4).
screws and tighten to 56 ± 6 kg.m (405 ± 43 NOTE: To retract the rod, connect air pressure to the
ft.lbs.) torque. spring cylinder.
FIGURE 5-46. BRAKE COUPLING FIGURE 5-48. PARK BRAKE SPRING CYLINDER
1. Brake Disc 4. Holder
5. Support 1. Spring Cylinder 3. Connecting Pin & Clevis
2. Coupling
6. Capscrews 2. Tool 4. Lever
3. Capscrew
Refer to "Parking Brake Adjustment", Section "J", Brake

b. Install plate (1, Figure 5-47) on one side tempo-
System, to adjust park brake assembly.
rarily.
c. Fit pad (2) and install caliper (3).
d. Install plate on other side and tighten fully.
Apply Three Bond thread tightener # 1374 to
plate mounting capscrews and tighten to 94.5
kg.m (684 ft.lbs.) torque.
NOTE: Make a clearance of 0.1 mm (0.004 in) between
the plate and the caliper.
FIGURE 5-47. CALIPER

1. Plate 3. Caliper
2. Pad

FINAL DRIVE PLANETARIES AND WHEEL HUBS
FINAL DRIVE
To Check Oil Level
The final drive uses a planetary gear mechanism to
reduce the rotation speed and produce a greater driv- Stop the machine so that the casting line is horizontal
ing torque. Of all the components in the drive train, the and the drain plug is at the bottom. Remove the fill plug
final drive has to bear the greatest stresses. The and check the oil level. If the oil level is not near the
lubrication system should be maintained properly to lower edge of the plug hole, add oil until it reaches this
insure long life of the gears and bearings. level.
FIGURE 6-1. FINAL DRIVE PLANETARY
1. Carrier 5. Button 9. Retainer SPECIFICATION:

2. Planet Gear Shaft 6. Cover 10. Inner Hub Splash-type Lubrication
3. Planet Gear (39 Teeth) 7. Ring Gear (99 Teeth) 11. Drive Shaft Ratio: 6.50
4. sun gear (18 teeth) 8. Spacer 12. Wheel Hub Oil: EO30-CD, 64 l (17 gal)
13. Seal Drain Each Side
G06005 Final Drive Planetaries and Wheel Hubs G6-1

CARRIER ASSEMBLY
Removal
1. Drain 64 l (17 gal) of oil from the final drive case.
NOTE: If the drain plug is not at the bottom, use a
hydraulic jack (50t) to jack up the machine, then turn
the hub.

3. Remove button (2).
4. Install an eye-capscrew at the end of drive shaft
(3, Figure 6-3), then use a bar to pull out drive
shaft.
5. Remove snap ring (4). FIGURE 6-3. DRIVE SHAFT
6. Remove sun gear (5). 1. Carrier Assembly 4. Snap Ring
7. Remove spacer (2). 2. Spacer 5. Sun Gear
3. Drive Shaft
Be sure lifting device is of adequate capacity to

handle 390 kg (860 lbs.) safely.
8. Remove carrier assembly (1).
FIGURE 6-2. COVER AND BUTTON

1. Cover 2. Button
FIGURE 6-4. CARRIER ASSEMBLY

1. Carrier Assembly 2. Rim
G6-2 Final Drive Planetaries and Wheel Hubs G06005

Installation
Be sure lifting device is of adequate capacity to
handle 390 kg (860 lbs.) safely.
1. Install carrier assembly (1, Figure 6-4).
2. Install spacer (2 Figure 6-3).
3. Install sun gear (5).
4. Install snap ring (4).
5. Install an eye-capscrew at the end of drive shaft
(3), then use a bar to Install drive shaft.
6. Install button (2, Figure 6-2).
8. Add oil to the final drive case. Refill to the specified FIGURE 6-6. BEARINGS
level and check the oil level again. Refer to "Lu-
brication and Service", Section "P", for the proper 1. Bearings 2. Spacer
oil.
3. Pull out pinion gear assembly (5), and remove two

bearings (1) and spacer (2). (See Figures 6-5 and
FINAL DRIVE CARRIER 6-6)
Disassembly 4. Remove outer race (1, Figure 6-7) and spacer (2).
1. Remove four capscrews (6, Figure 6-5) and six NOTE: The bearing is an adjustment-free bearing, so
capscrews (7), then remove plate (3). keep together as a set in a safe place.
2. Using a press, remove shaft (4). 5. Remove snap ring (3).
6. Remove spacer (8, Figure 6-5) from carrier.
FIGURE 6-5. CARRIER

1. Bearings 5. Pinion Gear
2. Spacer Assembly FIGURE 6-7. OUTER BEARING RACES
3. Plate 6. Capscrews 1. Outer Race 3. Snap Ring
4. Shaft 7. Capscrews 2. Spacer
8. Spacer

FINAL DRIVE ASSEMBLY
Assembly Disassembly
1. Install spacer (8, Figure 6-5) to carrier. 1. Remove rear wheel assembly. Refer to "Rear
Wheel Removal", this section.
2. Install snap ring (3, Figure 6-7).
2. Remove carrier assembly as previously de-
3. Fit spacer (2), and press fit outer race (1).
scribed.
4. Set spacer (2, Figure 6-5) and bearing (1) in
3. Shim retainer removal;
position, then raise pinion gear and assemble,
and install bearing (1) from top. a. Using three evenly spaced tools 790-438-1150
(3, Figure 6-8), secure inner gear (1) to outer
5. Push pinion gear assembly (5) into carrier. gear (2).
6. Fit plate (3) with capscrew (1) temporarily, then NOTE: To install the tool, remove capscrew (4) from
install 2 guide capscrews to shaft (4), and press the outer gear, and use the three tool mounting tap
fit. holes in the inner gear.
NOTE: Expand fit the shaft, of press fit with a press. NOTE: To prevent damage to the floating seal, always
remove before removing retainer (1, Figure 6-9).
7. Apply Three Bond (TB1374) thread tightener to

capscrews (7) and tighten to 28.5 kg.m (206 b. Remove mounting capscrews (2, Figure 6-9),
ft.lbs.) torque. After rotating pinion gear 5 - 6 then remove retainer (1) and shims.
turns, tighten six capscrews (2) and four cap- NOTE: Check the number and thickness of the shims,
screws (6) to specified torque again. and keep together in a safe place.
FIGURE 6-8. GEARS AND RETAINER

1. Inner Gear 3. T oo l (79 0-438 -
1150)
2. Outer Gear
4. Capscrew

FIGURE 6-9. RETAINER FIGURE 6-11. INNER GEAR AND RING GEAR
1. Retainer 2. Capscrews 1. Capscrews 3. Inner Hub

2. Holder 4. Ring Gear
4. Lift off ring gear assembly (1, Figure 6-10). Disas- 5. Rear wheel hub assembly.
semble ring gear assembly as follows. a. Sling rear wheel hub assembly (1, Figure 6-12)
a. Remove mounting capscrews (1, Figure 6-11), or support with forklift, then remove nuts (2,
then remove holder (2). Figure 6-13).
b. Remove inner hub (3) from ring gear (4).
FIGURE 6-12. REAR WHEEL HUB

FIGURE 6-10. RING GEAR
1. Hub Assembly 2. Housing
1. Ring Gear 2. Hub
Assembly

FIGURE 6-13. REAR WHEEL HUB
1. T oo l (79 0-438 - 2. Nut FIGURE 6-15. HUB AND BEARING
1150)
1. Hub Assembly 3. Outer Race
2. Outer Race
b. Pull out wheel hub assembly (2, Figure 6-14)

partly, remove bearing (1), then remove wheel
assembly.
6. Remove bearing (1, Figure 6-16).
NOTE: The bearing comes out easily, so be extremely
careful not to let it drop.
c. Remove outer races (2 & 3, Figure 6-15) from

wheel hub assembly (1).
FIGURE 6-16. BEARING

FIGURE 6-14. HUB AND BEARING 1. Bearing 2. Axle
1. Bearing 2. Hub Assembly

Assembly 4. Shim, retainer
1. Install bearing (1, Figure 6-16). a. Adjust preload of bearing as follows.
1) With no shims assembled, install retainer (1,
2. Wheel hub assembly
Figure 6-9) temporarily with capscrews (2).
a. Using push tool 792-104-4501, press fit outer 2) Remove tool (1, Figure 6-13) from 3 places,
races (2 & 3, Figure 6-15) in wheel hub (1). and tighten nuts.
b. Install O-ring, then raise rear wheel hub assem- 3) Rotate wheel hub 5 - 6 times and tighten
bly (1, Figure 6-12), and set to inner gear. capscrews uniformly to 15 ±0.5 kg.m (108 ±
c. Install bearing (1, Figure 6-14). Apply Three 3.6 ft.lbs.) torque.
Bond (TB1374) thread tightener to nuts (2,
Figure 6-13) and tighten nuts to 56 kg.m (405
NOTE: If the capscrews are tightened without rotating
ft.lbs.) torque. the wheel hub, the bearing will not settle, and the
correct preload cannot be obtained.
NOTE: Do not remove tools (1, Figure 6-13) until the
retainer has been completely secured. 4) Using depth micrometer (1, Figure 6-17)
measure dimension "c" between end of shaft
and outer edge of retainer (2).
3. Ring gear assembly
5) Remove retainer, and measure the thickness
a. Assemble ring gear assembly as follows. "a" of retainer. Select a shim thickness which
b. Set inner hub (3, Figure 6-11) to ring gear (4). is dimension "b", by using the formula below.
c. Install holder (2), and apply Three Bond (b=c-a) and add 0.3 mm (0.012 in).
(TB1374) thread tightener to mounting cap- b. Insert shim pack as determined above, then
screws (6) and tighten. install retainer (1, Figure 6-9). Apply Three
d. Raise ring gear assembly (1, Figure 6-10) and Bond (TB1374) thread tightener to capscrews
install. (2) and tighten to 94.5 kg.m. (684 ft.lbs.).
NOTE: Rotate the wheel hub 5 - 6 times and tighten
the capscrews uniformly until the tightening torque in
constant.
NOTE: After tightening the capscrews, rotate the
wheel hub, and check that there is no abnormality in
rotation.
5. Refer to "Carrier Assembly Installation", this sec-

tion, and install carrier assembly.
6. Refer to "Rear Wheel Assembly Installation", this
section, and install rear wheel assembly.
FIGURE 6-17. SHIM ADJUSTMENT

1. Micrometer 2. Retainer

NOTES

SECTION H
SUSPENSIONS
INDEX
FRONT SUSPENSION
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-1
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-5
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-6
Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-7
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-7
Attenuation Valve Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-8
REAR SUSPENSION
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-1
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-2
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-3
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-3
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-4
Spherical Bearing Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-5
OILING AND CHARGING PROCEDURES

GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-1
EQUIPMENT LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-1
FRONT SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-1
Front Suspension Oiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-2
Front Suspension Nitrogen Charging . . . . . . . . . . . . . . . . . . . . . . . . H4-3
REAR SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-5
Rear Suspension Oiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-5
Rear Suspension Nitrogen Charging . . . . . . . . . . . . . . . . . . . . . . . . H4-6
H01012 Index H1-1

H1-2 Index H01012
SUSPENSION SYSTEM
FIGURE 2-1. SUSPENSION SYSTEM

1. Front Suspension Cylinder 3. Rear Suspension Cylinder 5. A-arm
2. Rear Axle Support 4. Radius Rod
The suspension system supports the weight of the The front suspension consists of two basic com-
chassis, and absorbs the shock from uneven road ponents; a suspension cylinder and an A-arm.
surfaces to provide a comfortable ride for the operator.
In addition to these functions, the front suspension
At the same time, it maintains the stability of the ma-
employs an optional variable rate suspension system.
chine by ensuring that all four wheels are always in
In this system, the force of the suspension is automat-
contact with the ground surface. In this way, it allows
ically changed by selecting the damping force to match
the machine to demonstrate its full performance in
the travel conditions and load conditions. This further
items such as acceleration, braking, and turning, even
increases the stability and riding comfort of the ma-
when traveling at high speed.
chine.
The suspensions are hydro-pneumatic components
If a variable rate suspension system or the payload
containing oil and nitrogen gas. The oil and gas in the
meter is installed on the vehicle, both front suspension
four suspension cylinders carry the gross truck weight
cylinders will have a pressure sensor in place of the
less wheels, spindles and final drive assembly.
discharge plug.
H02009 12/91 Front Suspensions H2-1

Front suspension The damping force is produced inside valve assembly
(11, Figure 2-3) with orifice plate (3, Figure 2-4) and leaf
The front suspension cylinder functions as a shock
springs (1) and (2). They restrict the flow of oil between
absorber and spring, and is connected by spherical
oil chamber (B) and oil chamber (C), and create a
bearings to the lower A-arm and main frame. The
damping force.
wheels move up and down in accordance with the
retraction and extension of the suspension cylinder to
maintain the proper alignment for the wheels and to
improve the stability of the machine.
The inside of the cylinder contains oil (B, Figure 2-3),
and charged with nitrogen gas (A). Oil (B) and oil
chamber (C) are connected by tube (10) and valve
assembly (11).
When the machine is traveling, the wheels follow the
unevenness of the road surface, and an external force
in the up-down direction is applied to the suspension
cylinder. When this happens, the volume of the nitro-
gen in the gas chamber changes elastically under the
input force, and absorbs the external force. The nitro-
gen gas is sealed by a rod and oil, so it is always
subjected to a pressure corresponding to the external
force, and acts as a spring.
FIGURE 2-3. FRONT SUSPENSION

1. Feed Valve 9. Air Bleed Valve
2. Retainer 10. Tube
3. Flange 11. Valve Assembly
4. Stopper
5. Cylinder (with axle) A. Gas Chamber
6. Rod B. Oil Chamber
7. Wear ring C. Oil Chamber
FIGURE 2-2. FRONT SUSPENSION 8. Air Bleed Valve
H2-2 Front Suspensions H02009 12/91

1. When retracting, the nitrogen gas is compressed Removal
by the external force from the road surface. The
The suspension cylinders require only normal care
oil in oil chamber (B) flows from oil chamber (B)
when handling as a unit. However, after being disas-
through valve assembly (11, Figure 2-3) and tube
sembled these parts must be handled carefully to pre-
(10) to oil chamber (C). The oil flowing through the
vent damage to the machined surfaces. Surfaces are
valve from direction Y to orifice plate (3, Figure
machined to extremely close tolerances and are pre-
2-4) is throttled by orifices in four places to gen-
cisely fitted. All parts must be completely clean during
erate a damping force.
assembly.
2. When extending, the external force from the road
1. Park unloaded truck on hard level surface. Block
surface weakens, the pressure of the nitrogen gas
wheels and apply parking brake. Refer to Section
extends the rod, and the oil in chamber (C, Figure
“G”, "Front Tire and Rim", and to "Front Wheel
2-3) passes through tube (10) and valve assembly
Hub", to remove front wheel, tire and front wheel
(11) to oil chamber (B). The oil flowing through the
hub.
valve flows from direction Z and passes through
two orifices from the orifice plate to generate a 2. Remove cover from top of suspension. If equipped
damping force. with payload meter or variable rate suspension,
disconnect wire lead from sensor.
The variable rate suspension also controls the damping
force by a variable orifice located in valve assembly (11,
Figure 2-3). Refer to "Options and Special Tools", Sec-
tion "M" for information concerning the variable rate
suspension.
Turning the complete valve assembly more than
three turns may result in the valve assembly being
forced out of the suspension by the gas pressure
inside.
NOTE: If oil is discharged with the gas, tighten the

valve slightly so only the gas will be discharged.
3. Wearing face mask or goggles, discharge nitrogen
pressure from suspension by loosening dis-
charge plug (2, Figure 2-5) no more than one turn.
After all nitrogen pressure has been relieved,
tighten the valve to 4.5 ± 0.5 kg.m (33 ± 4 ft.lbs.)
torque.
NOTE: If equipped with a pressure sensor, refer to

"Oiling and Charging Procedures", this section, for
discharging nitrogen gas.
FIGURE 2-4.
1. Leaf Springs 3. Orifice Plate
2. Leaf Springs
FIGURE 2-5. VALVE AND PLUG LOCATION

1. Air Bleed Valve 3. Charging Valve
2. Discharge Plug

1. Elbow Fitting 2. Brake Hoses
FIGURE 2-8. STEERING KNUCKLE
1. Capscrew 2. Capscrew
4. Remove the brake hoses (2, Figure 2-6).

5. Remove grease tubes (4, Figure 2-7) and elbows
(3). 8. If equipped with variable rate dampening, discon-
nect the air lines from the air cylinder on the
6. Remove pins (2) and (5) and tie rod (1). suspension.
7. Remove steering cylinder rod (6). 9. Remove capscrew (2, Figure 2-8) by rotating the
knuckle arm approximately 40° towards the chas-
sis.
10. Steer the knuckle arm to straight ahead position.
Place a jack under the king pin and raise up.
Remove capscrews (1).
FIGURE 2-7. STEERING LINKAGE REMOVAL
1. Tie Rod 4. Grease Tubes

2. Pin 5. Pin
3. Elbow 6. Steering Cylinder

Installation
1. Clean all paint or protective coating from mounting
surface of suspension. Assure that mount sur-
Suspension weighs approximately 681 kg (1,500 faces of suspension and A-frame are smooth and
lbs.). Be certain that lifting device is of adequate free of any oil.
capacity.
10. Sling suspension to a suitable lifting device that can

safely carry 681 kg (1,500 lbs.). See Figure 2-9.
Suspension weighs approximately 681 kg. (1,500
11. Remove pin (2) and two spacers and move sus- lbs.). Be certain that lifting device is of adequate
pension away from frame. capacity.
2. Attach lifting device to suspension housing and

raise into position on A-arm. Install top cylinder
pin (2, Figure 2-9.) with a spacer on each side of
the suspension.
3. Install capscrews (1, Figure 2-8).
4. Rotate the knuckle arm approximately 40° towards
the chassis and install capscrew (2).
5. Connect steering cylinder rod (6, Figure 2-7) to
knuckle with pin (5).
6. Connect tie rod (1) to knuckle with pin (2).
7. Install elbows (3) and grease tubes (4).
8. Connect brake hose (2, Figure 2-6).
9. Install front hub, wheel and tire. Refer to Section
"G" for installation procedures.
10. Install brake hoses
11. After installation of suspension, it will be necessary
to check oil level and charge with nitrogen gas.
Refer to "Suspension Oiling and Charging" proce-
dure, this section.
1. Suspension Cylinder 2. Cylinder Pin

Disassembly
1. Remove top suspension cover. 3. Remove flange mounting bolts (7) and air bleed
plug (15).
2. Remove charging valve (8, Figure 2-10) and dis-
charge plug (9). 4. Raise to position where cylinder rod assembly
contacts stopper (3) and moves stopper to step
in cylinder.
FIGURE 2-10. FRONT SUSPENSION REPAIR

1. Wear Ring 5. Flange 9. Discharge Plug 13. Dust Seal
2. Rod Assembly 6. Retainer 10. Bushing 14. Plate
3. Stopper 7. Capscrew 11. Seal 15. Air Bleed Valve
4. Suspension Housing 8. Charging Valve 12. Bushing

Assembly
Clean all components thoroughly. Lightly coat all O-
rings, backup rings, seals and wiper with petroleum
jelly or suspension oil.
1. Install wear ring (1, Figure 2-10) to cylinder rod (2).

2. Press fit bushing (10) in flange (5), and install seal
(11).
3. Press fit bushing (12) to retainer (6), and install
dust seal (13).
FIGURE 2-11. NOTE: Be careful not to deform the bushings during

installation.
1. Rod Assembly 3. Tool (790-450-1120 )
2. Capscrew 4. Cylinder Housing
4. Install stopper (3) to cylinder rod (2).
5. Install tool 790-450-1120 (3, Figure 2-11) to cylin- 5. Install flange (5), retainer (6), and plate (14) to
der. cylinder rod.
6. Raise cylinder assembly until it rises approx. 50 6. Using blocks, stand suspension housing upright.
mm (2 in) from floor, then hit from top of tool (3) Add 20 l (5.3 gal) of engine oil to inside of cylinder
with a plastic hammer so that stopper passes from housing. Refer to Section "L", Lubrication and
step in cylinder. Service for oil specifications.
7. Remove tool (3), then remove cylinder rod assem- 7. Lift cylinder rod assembly (2), and install into
bly. cylinder housing.
8. Remove plate (14, Figure 2-10), retainer (6), flange
NOTE: When assembling the rod assembly in the
(5), and stopper (3) from rod assembly (2).
cylinder, if the rod assembly is inserted too far, the oil
9. Remove dust seal (13) and bushing (12) from will spurt out, so stop at a position where the oil does
retainer (6). not spurt out.
10. Remove seal (11) and bushing (10) from flange (5).
After installing the suspension completely to the frame,
11. Remove wear ring (1) from cylinder rod (2). adjust the oil and gas levels.
8. Secure flange (5), retainer (6), and plate (14) to

Inspection
cylinder with capscrews (7) and tighten to stand-
1. If scratches or scores are found in housing or on ard torque.
suspension tube, contact your HAULPAK® Dis-
9. Install air bleed valve (15), discharge plug (9) and
tributor.
charging valve (8). Tighten each item to 4.5 ± 0.5
kg.m (33 ± 4 ft. lbs.) torque.
10. Install cover on top of suspension.

ATTENUATION VALVE (FIXED RATE)
Disassembly Assembly
1. Remove four capscrews (1, Figure 2-12) and re- 1. Assembly of orifice plate assembly
move orifice plate assembly (2) from valve body a. Install two pins (10, Figure 2-12) in orifice plate
(3). (9).
2. Sub-disassembly of orifice plate assembly b. After setting three kinds of oblong leaf springs
a. After removing capscrew (3, Figure 2-13), re- (1, Figure 2-13) on orifice plate, install plate (6,
move stopper plate (5), plate (6, Figure 2-12), Figure 2-12) while adjusting pin.
oblong leaf spring (1, Figure 2-13), circular leaf c. After setting three kinds of circular leaf springs
spring (4) from orifice plate (2). (4, Figure 2-13) install and tighten capscrew (3).
b. Remove pin (10, Figure 2-12) from orifice plate
(9). NOTE: Oblong leaf spring and circular leaf spring are
installed to face chamfering side to orifice plate side.
2. Install orifice plate assembly (2, Figure 2-12) with

together O-ring on valve body (3), then install and
tighten four capscrews (1).
FIGURE 2-13. ORIFICE PLATE

1. Oblong Leaf Spring 4. Circular Leaf Spring
2. Orifice Plate 5. Stopper Plate
3. Capscrew
FIGURE 2-12. ATTENUATION VALVE
1. Capscrew 6. Plate
2. Orifice Plate Assembly 7. Oblong Leaf Spring
3. Valve Body 8. Circular Leaf Spring
4. Capscrew 9. Orifice Plate
5. Stopper Plate 10. Pin

REAR SUSPENSIONS
The suspensions are hydro-pneumatic components

containing oil and nitrogen gas. The oil and gas in the
four suspensions carry the gross truck weight less
wheels, spindles and final drive assembly. The rear
suspension cylinders consist of two basic compo-
nents: a suspension housing attached to the truck
frame and a suspension rod attached to the final drive
center case.
Each rear suspension cylinder contains a charging

valve (2, Figure 3-1) and a discharge/air bleed valve
(1). The charging valve is used for nitrogen charging
and the discharge valve for relieving nitrogen pres-
sure. See “Oiling and Charging Procedures” this sec-
tion, for proper charging and discharging instructions.
The suspension cylinder requires only normal care

when handling as a unit. However, after being disas-
sembled, these parts must be handled carefully to
prevent damage to the machined surfaces. Surfaces
are machined to extremely close tolerances and are
precisely fitted. All parts must be completely clean
during assembly.
If the vehicle is equipped with the payload meter
system, both rear suspension cylinders will have a
pressure sensor in place of the discharge/air bleed
valve.
FIGURE 3-1. REAR SUSPENSION
1. Discharge/Air Bleed 10. Packing

Valve 11. Bushing
2. Charging Valve 12. Retainer
3. Wear Ring 13. Seal
4. Rod 14. Bolt
5. Ball 15. Spring Washer
6. Bushing 16. Oil Area
7. Flange 17. Cavity
8. O-ring 18. Nitrogen Gas Area
9. Ring
H03012 Rear Suspensions H3-1

Removal
The suspension cylinder has the function of both a 1. Park unloaded truck on hard level surface. Block
shock absorber and a spring. wheels and apply parking brake.
1. When a fixed amount of oil is sent from oil area 2. Raise and support the rear of the frame of the truck
(16, Figure 3-1) through orifices (5) and (A) to for rear suspension removal and installation.
cavity (17), the oil is throttled by the orifices and
3. Wearing face mask or goggles, crack open dis-
a shock-absorbing effect is obtained.
charge valve and discharge nitrogen pressure
2. Retracting action from suspension. If oil escapes with the nitrogen,
a. When the machine is traveling and it hits a tighten valve slightly. Tighten discharge valve
bump or object on the road, the wheels are after all nitrogen is released from suspension.
pushed up, and the cylinder rod is pushed 4. Remove suspension lower mount pin (2, Figure
inside the cylinder. 3-2) retainer bolt.
b. When this happens, the nitrogen gas inside
area (18) is compressed, the oil in area (16) is
sent through both orifices (5) and (A) to cavity
(17), and cavity (17) is filled quickly.
3. Extending action
a. After the machine has passed over any bump Suspension weighs approximately 240 kg. (530
or object on the road surface, the cylinder is lbs). Be certain that lifting device is of adequate
pulled down by the weight of the wheels and capacity.
axle and pushed down by the pressure of the
nitrogen inside area (18). 5. Attach lifting device to suspension. Suspension
b. As a result, the amount of oil in cavity (17) is weighs approximately 240 kg.(530 lbs.)
reduced, and pressure is applied to the oil
remaining in cavity (17). 6. Remove retaining capscrew and top mount pin (1,
Figure 3-2) and spacers and remove suspension
c. This pressurized oil closes orifice (5) with check from truck.
ball (5), and is sent to area (16) through only
orifice (A), so the flow of oil passing through the 7. Retract rod and move suspension to work area.
orifice is controlled so that it is slower than
during retraction. In this way, the amount of oil
returning to area (16) is restricted, providing a
shock absorbing effect.
FIGURE 3-2. REAR SUSPENSION

1. Top Pin 3. Suspension
2. Lower Pin Cylinder
H3-2 Rear Suspensions H03012

Installation Disassembly
1. Attach lifting device to suspension. Suspension 1. Using blocks, stand the cylinder assembly upright
weighs approximately 240 kg.(530 lbs.) with housing end down.
2. Remove protective skirt attached to housing and
cover over charging and air bleed valves.
3. Remove discharge/air bleed valve (1, Figure 3-1)
and charging valve (2).
4. Remove flange mounting capscrews (14).
Suspension weighs approximately 240 kg. (530 5. Use a hoist to raise cylinder rod assembly (1,
lbs). Be certain that lifting device is of adequate Figure 3-3) slowly with plate (2) and flange (3) still
capacity. installed, and remove from cylinder housing (4).
Drain oil from cylinder.
6. Remove O-ring (5) and backup ring (6).
2. Position suspension on truck and install upper 7. Remove plate (2, Figure 3-4) and flange (3) from
mount pin (1, Figure 3-2) and spacers and pin rod assembly (1).
retaining capscrew. 8. Remove bushing (2, Figure 3-5) and U-packing
3. Install lower mount pin (2, Figure 3-2) and spacers (3) from flange (1).
and pin retaining capscrew. 9. Remove seal (2, Figure 3-6) and bushing (3) from
4. After installation of suspension, it is necessary to plate (1).
check oil level and charge with nitrogen gas. 10. Remove wear ring (2, Figure 3-7) from rod (1).
Refer to “Suspension Oiling and Charging Proce-
dure”, this section.
FIGURE 3-3. SUSPENSION ROD

1. Cylinder Rod 4. Housing
2. Plate 5. O-Ring
3. Flange 6. Backup Ring

Assembly
NOTE: Clean all parts thoroughly. Lightly coat all
O-rings, backup rings, seals and wipers with petroleum
jelly or suspension oil.
1. Install wear ring (2, Figure 3-4) to rod (1).
FIGURE 3-6. SUSPENSION PLATE AND FLANGE

1. Cylinder Rod 3. Flange
2. Plate
3. Install flange (3, Figure 3-6) over rod (1).
FIGURE 3-4. ROD AND WEAR RING 4. Install seal (2, Figure 3-7) and bushing (3) to plate
(1).
1. Cylinder Rod 2. Wear Ring
2. Install bushing (2, Figure 3-5) and U-packing (3)

to flange (1).
FIGURE 3-7. PLATE AND SEALS
1. Plate 3. Bushing
2. Seal
FIGURE 3-5. CYLINDER PACKINGS 5. Install plate (2, Figure 3-6) to rod (1).
6. Install backup ring (6, Figure 3-3) and O-ring (5)
1. Flange 3. U-Packing to flange.
2. Bushing
7. Install temporary plugs in charging and air bleed
valve ports.

8. Using blocks, stand cylinder upright. Fill inside of REAR SUSPENSION
cylinder housing with 17 l (4.5 gal) of engine oil. SPHERICAL BEARING REPAIR
Refer to “Section L”, “Lubrication and Service”,
for oil specifications. NOTE: If either top or bottom spherical bearings are to
be replaced with the suspension mounted on truck, be
9. Raise cylinder rod assembly (1, Figure 3-3), and sure truck frame is securely supported. Refer to Sus-
install into cylinder housing (4). pension Removal and Installation for procedure. Se-
NOTE: When installing the rod assembly into the curely support suspension as bearing is being
cylinder, if the rod assembly is inserted too far, the oil removed and installed.
will spurt out. If this occurs, do not attempt to insert rod
further into housing.
10. Refer to Figure 3-8. Coat the entire mating face Disassembly
“A” of flange (2) and retainer plate (1) with a thin 1. Remove retaining ring from mounting eye of hous-
layer of Liquid Gasket LG-5. Do not allow sealant ing or tube.
to contact bore area “B”.
2. Remove bearing.
Inspection
1. Inspect spacers and mounting eye bearing bores
for damage. Inspect retainer ring grooves. Repair
or replace as necessary.
2. Inspect mount pin. Replace pin if worn or dam-
aged.
Assembly
1. Install retainer ring in groove.
2. Press spherical bearing in mount eye bore.
FIGURE 3-8. LIQUID GASKET SEAL AREA 3. Install remaining retaining ring.
4. Refer to Suspension Installation.
1. Retainer A-Sealant Area
2. Flange B-No sealer this area 5. Be sure grease is applied to bearing before oper-
ating truck.
6. After suspension is installed on truck, it may be
necessary to charge suspension with nitrogen.
11. Install plate (2, Figure 3-6) together with flange (3)
Refer to Suspension Oiling and Charging proce-
with 16 mounting bolts. Tighten to 157 - 196 Nm
dure, this section.
(116 - 145 ft. lbs.) torque.
12. Fit packing to air bleed valve (1, Figure 3-1) and
install. Tighten to 4.5 ±0.5 kg.m (33 ±4 ft.lbs.)
torque.
13. Install charging valve (2, Figure 3-1). Tighten to
4.5 ±0.5 kg.m (33 ±4 ft.lbs.) torque.
NOTE: The charging valve and air bleed valve can be
installed in either place.
14. Install protective skirt to housing. Install cover over
charging and air bleed valves.

NOTES

OILING AND CHARGING PROCEDURES
GENERAL
NITROGEN GAS SPECIFICATIONS
Suspensions which have been properly charged will Nitrogen gas used in sus-
provide improved handling and a better ride while pension cylinders must Property Value
improving the service life of the truck main frame and meet or exceed CGA Speci- Nitrogen 99.9% Min.
suspensions. fication Water 32 PPM Max.
G-10.1 for Type 1, Grade F Dew Point -55°C(-68°F) Max.
Nitrogen Gas. Oxygen 0.1% Max.
NOTE: Inflation pressures and exposed piston lengths
are calculated for a normal truck gross vehicle weight
(GVW). Any accumulation of dirt/mud/debris on the
truck or in the body should be removed before starting
these procedures.
Additions to truck weight (tailgates, body liners, water
All suspensions are charged with compressed ni-
tanks, etc.) should be considered part of the payload.
trogen gas with sufficient pressure to cause injury
Keeping the truck GVW within the specification will
or damage if improperly handled. Follow all safety
result in a better ride and will extend the service life of
notes, CAUTIONS, and WARNINGS in these proce-
the truck main frame and suspensions.
dures to prevent accidents during servicing and
charging.
Proper charging of suspensions requires that three (3)
basic conditions be established in the following order: FRONT SUSPENSION
1. Oil level must be correct. 1. Park unloaded truck on a hard level surface. Block
wheels, apply parking brake.
2. Suspension piston rod extension for nitrogen
charging must be correct and this dimension be 2. Check that the bottom of the cylinder cover is
maintained during nitrogen charging. within the range marked by arrows (Figure 4-1)
for correct nitrogen charge.
3. Nitrogen charge pressure must be correct.
3. If the suspension is within the area indicated by
arrows, no service is necessary for the front sus-
For best results, suspensions should be charged in pensions. See "NOTE" below.
pairs (fronts together and rears together). If rears are If suspension is not within the area indicated by
to be charged, the fronts should be charged first. the arrows, the front suspensions will have to be
serviced.
NOTE: Set up dimensions specified in the charts must
be maintained during oiling and charging procedures. NOTE: The oil level should be checked:
However, after truck has been operated, these dimen- • Before charging or adding nitrogen.
sions may vary. • When there are signs of oil leakage.
• After rebuild/repair and the suspension is
installed on the truck .
EQUIPMENT LIST
1. Service Kits:
a. EC6027 Oil Charging Kit (Figure 4-5)
b. EC3331 Nitrogen Charging Kit (Figure 4-6)
2. Jacks and/or Overhead Crane
3. Oil (MIL-L-2104C, SAE 10W)
4. Dry Nitrogen (See Nitrogen Specifications Chart)
FIGURE 4-1. FRONT SUSPENSION HEIGHT
H04012 11/98 Oiling and Charging Procedures H4-1

Front Suspension Oiling
Lifting equipment (crane or hydraulic jacks) must

be of sufficient capacity to lift the truck weight. Be
certain that all personnel are clear of lift area be-
fore lift is started.
Each suspension is equipped with a charging valve (3, FIGURE 4-2. VALVE AND SENSOR LOCATION
Figure 4-2), air bleed valve (1) and a discharge plug
1. Air Bleed Valve 3. Charging Valve
(2) or a pressure sensor assembly. The pressure
2. Discharge Plug
sensor assembly is used if the truck is equipped with
an on-board load weighing system or variable rate
suspension and takes the place of the discharge plug.
1. Park unloaded truck on a hard level surface.
Block wheels, apply parking brake.
2. Remove outside covers and thoroughly clean
area around charging valves (3, Figure 4-2) on
the suspensions.
3. If equipped with a pressure sensor, disconnect
the pressure sensor wire lead.
4. Set hydraulic jack (1, Figure 4-3) under the main
frame and raise jack to contact the frame.
NOTE: When releasing the nitrogen gas, there is
danger that releasing the gas from the valve core of
charging valve (3, Figure 4-2) will damage the valve
core, so remove the gas by loosening the discharge
plug (2) or sensor valve assembly (2, Figure 4-4).
FIGURE 4-3. OIL HEIGHT

1. Jack (50 ton) A: 97 ±3 mm
Turning the discharge plug more than three turns 2. Frame (3.8± 0.12 in)
may result in the discharge plug being forced out
of the suspension by the gas pressure inside.
When loosening the pressure sensor valve assem-
bly, loosen only valve assembly (2, Figure 4-4). Do
not loosen the pressure sensor (4) or adapter (3).
Wear a face mask or goggles while relieving nitro-
gen pressure.

discharge plug (or pressure sensor) slightly so only the
gas will be discharged.
FIGURE 4-4. PRESSURE SENSOR
1. Schrader Valve 3. Adapter
2. Valve Assembly 4. Sensor
H4-2 Oiling and Charging Procedures H04012 11/98

5. Wearing face mask or goggles, discharge nitro- 12. Remove discharge plug (4) (or sensor valve as-
gen pressure from suspension by loosening the sembly if equipped), then operate oil pump until
discharge plug (2, Figure 4-2) one turn. If no bubbles come out with the oil from the dis-
equipped with a pressure sensor, loosen valve charge plug hole.
assembly (2, Figure 4-4) one turn. (DO NOT
13. When no more bubbles come out with the oil,
loosen more than one turn).
install and tighten the discharge plug to 4.5 ±0.5
6. Operate the hydraulic jack (1, Figure 4-3) so that k.gm (33 ±3 ft.lbs.) torque.
dimension "A" of the cylinder is 97 ±3 mm (3.8 ±
14. After filling with oil, remove the oil pump and
0.12 in.)
fittings, then install charging valve (3) and tighten
7. After all nitrogen pressure has been relieved, valve to 4.5 ±0.5 k.gm (33 ±3 ft.lbs.) torque.
close the discharge plug (4, Figure 4-5) (or sensor
valve assembly if equipped).
8. Remove charging valve (3), and install adapter
(2).
Front Suspension Nitrogen Charging
9. Connect hose (1) and oil pump (8).
NOTE: The discharge plug (4) must be installed and
the air bleed valve (5) loose to insure there are no air
pockets inside the suspension.
10. Loosen air bleed valve (5), then pump oil into Dry nitrogen is the only gas approved for use in
cylinder until no bubbles come out with the oil from suspensions. Charging of these components with
air bleed valve hole (6). oxygen or other gases may result in an explosion
which could cause fatalities, serious injuries
11. When no bubbles come out with the oil, tighten air and/or major property damage. Use only nitrogen
bleed valve (5) to 4.5 ±0.5 k.gm (33 ±3 ft.lbs.) gas meeting the specifications shown on page
torque. H4-1.
1. Remove caps from charging valves (3, Figure
4-2).
NOTE: Before installing regulator (11, Figure 4-6, blow
out the cylinder connector with nitrogen gas at 10
kg/cm2 (140 psi) or more, to clean out all dirt or dust.
(Dirt or dust in the system can cause suspension
failures.)
2. Open valve on gas cylinder, and check the pres-

sure reading of regulator gauge (1).
NOTE: Internal pressure of gas cylinder should be
somewhat higher than Suspension Charging Pressure
(see chart below Figure 4-7).
3. Turn "T" handles (6, Figure 4-6) of adapters (5)

completely counterclockwise
4. Be certain outlet valves (3) and inlet valve (4) are
closed (turned completely clockwise).
5. Attach charging valve adapters (5) to each sus-
FIGURE 4-5. OIL CHARGING KIT (EC6027) pension charging valve stem.
1. Hose 5. Air Bleed Valve 6. Turn "T" handles (6) clockwise (this will depress
2. Adapter 6. Air Bleed Hole core of charging valve and open gas chamber of
3. Charging Valve 7. Oil Pump Lever suspension).
4. Discharge Plug 8. Oil Pump

7. Turn handle of regulator (11) slowly clockwise, set 10. Turn handle (6) of valve adapter (5) fully counter-
the pressure reading of gauge (2) to the required clockwise to close charging valve. Then remove
pressure (see chart below Figure 4-7), then oper- charging equipment, remove jack, and install cov-
ate valves (3 & 4) to fill the suspension cylinders ers removed in step 2 of oiling procedure.
with nitrogen gas. NOTE: Do not lose the charging valve O-rings.
8. Fill the left and right cylinders at the same time.
Verify required charging pressure on gauge (10) 11. Install caps with O-rings on charging valves (3,
by closing valve (4). Figure 4-2).
9. When the left and right cylinders reach the speci-

fied length as shown in Figure 4-7, close valve (4,
Figure 4-6) to stop the flow of nitrogen gas. Turn
handle of regulator (11) counterclockwise to
close.
OILING CHARGING CHARGING

HEIGHT HEIGHT PRESSURE
DIMENSION
mm mm kg/cm2
(in.) (in.) (psi)
97±3 262±10
FRONT "A"
(3.8±0.12) (10.3±0.4) 39.5 ±5
319±3 484 ±10 (561 ±70)
FRONT "B"
(12.6±0.12) (19.1±0.4)
Dimension "A" is measured from the top of the cover

FIGURE 4-6. NITROGEN CHARGING KIT (EC3331) to the top of the suspension cylinder plate. Do not
include capscrews in measurement. Removal of
1. Nitrogen Cylinder Gauge
an access panel on the top cover is required.
2. Charging System Gauge
3. Manifold Outlet Valves (from gauge) Dimension "B" may be used without removal of the
4. Inlet Valve (from regulator) covers, if "ARROW" marks are missing or obscured.
5. Connection Valve w/EC2253 Adapter Installed
NOTE: Set-up dimensions specified in the charts
6. Valve “T” Handle
must be maintained during oiling and charging proce-
7. Discharge Plug
dures. However, after truck has been operated, these
8. Air Bleed Valve
dimensions may vary. After charging suspension,
9. Manifold
operate empty truck over a short course and then park
10. Charging Pressure Gauge (Suspensions)
truck on a level surface. Record dimensions again
11. Regulator Valve (Nitrogen Pressure)
and save for periodic reference.
12. Dry Nitrogen Gas (see Specifications, Page H4-1)
NOTE: Arrangement of parts may vary from illustration
above, depending on Charging Kit P/N.

REAR SUSPENSION NOTE: Oiling and nitrogen charging dimensions for
these suspensions must be measured from the bottom
1. Park unloaded truck on a hard, level surface. of rod diameter to the bottom of suspension cylinder
Block wheels, apply parking brake. plate (dimension "A" in Figure 4-11).
2. Thoroughly clean around charging valves on sus-
pensions. Remove protective covers from charg- 1. Use lifting equipment (crane or hydraulic jacks) to
ing valves. raise truck to establish the dimension for oiling
shown in the chart below Figure 4-11.
3. If equipped with pressure sensor, disconnect the
pressure sensor wire lead. 2. Remove outside covers and thoroughly clean
area around charging valves on the suspensions.
All suspensions are charged with compressed ni-

trogen gas with sufficient pressure to cause injury Make certain all personnel are clear and support
or damage if improperly handled. Follow all safety blocks are secure before relieving nitrogen pres-
notes, CAUTIONS and WARNINGS in these proce- sure from the suspension. Use a face mask or
dures to prevent accidents during servicing and goggles when venting nitrogen.
charging.
NOTE: When releasing the nitrogen gas, there is
danger that releasing the gas from the valve core of
charging valve (3, Figure 4-8) will damage the valve
Rear Suspension Oiling core, so remove the gas by loosening discharge plug
(4) or pressure sensor valve assembly (if equipped).
Lifting equipment (crane or hydraulic jacks) must

be of sufficient capacity to lift truck weight. Be Turning the discharge plug more than three turns
certain that all personnel are clear of lift area be- may result in the discharge plug being forced out
fore lift is started. of the suspension by the gas pressure inside.
When loosening the valve assembly (2, Figure 4-9),
loosen only the valve assembly (2). Do not loosen
the pressure sensor (4) or adapter (3).
Wear a face mask or goggles while relieving nitro-
gen pressure.
valve slightly so only the gas will be discharged.
FIGURE 4-8. OIL CHARGING KIT

1. Hose 4. Discharge/Air Bleed Valve FIGURE 4-9. PRESSURE SENSOR
2. Adapter 5. Oil Pump Lever 1. Schrader Valve 3. Adapter
3. Charging Valve 6. Oil Pump 2. Valve Assembly 4. Sensor

3. Wearing face mask or goggles, discharge nitro-
gen pressure from suspension by loosening dis-
charge plug (4, Figure 4-8) one turn. If equipped
with a pressure sensor, loosen valve assembly
(2, Figure 4-9) one turn.
(DO NOT loosen more than one turn).
4. After all nitrogen pressure has been relieved,
close the discharge plug (4, Figure 4-8) (or sensor
valve assembly if equipped). The suspension
should have collapsed slowly as gas pressure
was released. Truck weight should now be sup-
ported by the crane or jacks.
5. Remove charging valve (3), and install adapter
(2).
6. Connect hose (1) and oil pump (6).
7. Loosen discharge valve (4) one turn, then fill with
oil until no air bubbles are present in expelled oil
from the discharge valve.
8. When no more bubbles come out with the oil,
FIGURE 4-10. NITROGEN CHARGING KIT
tighten the discharge valve to 4.5 ±0.5 k.gm (33 (EC3331)
±3 ft.lbs.) torque.
1. Nitrogen Cylinder Gauge
9. After completion of supplying the oil, remove the 2. Charging System Gauge
oil pump, then install and tighten charging valve 3. Manifold Outlet Valves (from gauge)
(3) to 4.5 ±0.5 k.gm (33 ±3 ft.lbs.) torque. 4. Inlet Valve (from regulator)
5. Connection Valve w/EC2253 Adapter Installed
6. Valve “T” Handle
Rear Suspension Nitrogen Charging 7. Discharge/Air Bleed Valve
8. Dry Nitrogen Gas (see Specifications, Page H4-
1)
9. Manifold
10. Charging Pressure Gauge (Suspensions)
11. Regulator Valve (Nitrogen Pressure)
Lifting equipment (crane or hydraulic jacks) must NOTE: Arrangement of parts may vary from illustration
be of sufficient capacity to lift the truck weight. Be above, depending on Charging Kit P/N.
certain that all personnel are clear of lift area be-
fore lift is started. 2. Remove caps from charging valves (3, Figure
1. Raise rear of truck with crane or jacks to provide 4-8).
dimensions shown in chart below figure 4-11 NOTE: Before installing regulator (11, Figure 4-10),
blow out the connector with nitrogen gas at 10 kg/cm2
(140 psi) or more, to clean out all dirt or dust. (Dirt or
dust in the system causes failures.)
3. Open valve on gas cylinder, and check the pres-

Dry nitrogen is the only gas approved for use in
sure reading of regulator gauge (1).
suspensions. Charging of these components with
oxygen or other gases may result in an explosion NOTE: Internal pressure of gas cylinder should be
which could cause fatalities, serious injuries somewhat higher than Suspension Charging Pressure
and/or major property damage. Use only nitrogen (see chart below Figure 4-11).
gas meeting the specifications shown on page
H4-1. 4. Turn "T" handles (6, Figure 4-10) of adapters (5)
completely counterclockwise.

5. Be certain outlet valves (3) and inlet valve (4) are
closed (turned completely clockwise).
6. Attach charging valve adapters (5) to each sus-
pension charging valve stem.
7. Turn "T" handles (6) clockwise (this will depress
core of charging valve and open gas chamber of
suspension).
8. Turn handle of regulator (11) slowly clockwise, set
the pressure reading of gauge (2) to the required
pressure (see chart below Figure 4-11), then
operate valves (3 & 4) to fill the suspension
cylinders with nitrogen gas.
9. Fill the left and right cylinders at the same time. FIGURE 4-11. REAR SUSPENSION
Verify required charging pressure on gauge (10).
OILING CHARGING
10. When the left and right cylinders reach the speci- CHARGING
HEIGHT HEIGHT
fied length as shown in the chart below Figure DIMENSION PRESSURE
mm mm
kg/cm2 (psi)
4-11, close valve (4) to stop the flow of nitrogen (in.) (in.)
gas. Turn handle of regulator (11) counterclock- 175 ± 3 242 ± 10 26.0 ± 5
wise to close off nitrogen flow. REAR "A"
(6.9 ± 0.12) (10.3 ± 0.8) (370 ± 70)
11. Turn handle (6) of valve adapter (5) fully counter- Dimension "A" is measured from the bottom of rod
clockwise to close charging valve. Then remove diameter to the bottom of the suspension cylinder
charging equipment. Remove the lifting equip- plate. Do not include capscrews in measurement.
ment (crane or hydraulic jacks) and install covers
removed in step 2 of oiling procedure.
NOTE: Set-up dimensions specified in the charts
NOTE: Be careful not to lose the O-rings off the
must be maintained during oiling and charging proce-
charging valves.
dures. However, after truck has been operated, these
12. Install caps with O-rings on charging valves (3, dimensions may vary. After charging suspension,
Figure 4-8). operate empty truck over a short course and then park
truck on a level surface. Record dimensions again
and save for periodic reference.
NOTE: Check for changes in length caused by vari-
ation in ambient temperature.
Depending on the ambient temperature, the gas in the

suspension may expand or contract, so the length will
also change. In territories where there are big differ-
ences in temperature throughout the year, inspect
periodically and adjust to keep the length within the
specified range shown in Figures 4-7 and 4-11.
The rear suspensions are now ready for operation.

Visually check piston rod extensions both with truck
loaded and empty. Record extension dimensions.
Maximum downward travel is indicated by the dirt ring
at the base of the piston. Operator comments on
steering and suspension rebound should also be
noted.

NOTES

SECTION J
BRAKE SYSTEM
INDEX
BRAKE CIRCUIT
Brake Circuit Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-1
Component Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-1
Emergency Relay Valve (RE-6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-2
Hand Brake (Retarder) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-5
Parking Brake Pilot Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-7
Parking Brake Relay Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-8
Brake Chamber (Front) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-9
Brake Chamber (Rear) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-9
Slack Adjuster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-10
Pressure Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-12
Stop Lamp Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-12
Parking Brake Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-13
Automatic Retarder Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-13
Front Brake Cut-Off Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-14
Brake Cooling Valve (BCV) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-15
Parking and Emergency Brake Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-16
Brake Valve (Treadle) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-18
BRAKE CIRCUIT COMPONENT SERVICE

Service Brake Treadle Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-1
Pressure Converters
Front . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-4
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-8
Slack Adjuster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-12
BRAKE CIRCUIT CHECKOUT AND ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . J4-1

Checking Front Pad Wear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-1
Checking Brake Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-1
Checking Rear Disc Wear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-2
Brake Bleeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-3
J01009 11/98 Index J1-1

FRONT BRAKES
Brake Pads
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-1
Brake Caliper Assembly
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-2
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-2
Inspection Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-2
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-3
REAR BRAKES
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-2
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-3
Inspection Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-4
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-4
PARKING BRAKE
Brake Pad
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-1
Parking Brake Caliper
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-2
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-2
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-3
Parking Brake Spring Cylinder
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-3
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-3
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-4
Parking Brake Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-5
Parking Brake Disc
Driveshaft Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-6
Parking Brake Disc Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-6
Inspection Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-7
Parking Brake Disc Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-7
Driveshaft Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-7
PARKING BRAKE RELEASE AFTER EMERGENCY APPLY
Release of Parking Brake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-7
Release of Emergency Brake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-8
J1-2 Index J01009 11/98

BRAKE CIRCUIT OPERATION
The operator of the truck applies the service brakes by If air system pressure decreases below 3.2 kg/cm2 (45
use of a foot operated treadle valve in the cab. The psi), the emergency brakes apply automatically. If air
brake circuit is an air controlled, hydraulically applied pressure continues to decrease, the parking brake will
dry and wet disc system. also apply.
During normal operation of the brake system Relay
Valve (RE-6), when the service brake pedal is de-
pressed, air is supplied from the air tank (dry) to the COMPONENT DESCRIPTION
pressure converters. The air pressure from the air tank
through the RE-6 valve should be equal to the air The main air system supplies air for actuation or
pressure from the service brake pedal. If a failure of release of all brake circuits. After the truck engine has
the air supply circuit or excessive air leakage from the been started, pressurized air flows through the wet air
(wet) air tank allows pressure to drop below 3.2 kg/cm2 tank to the dry air tanks to the emergency relay valves
(45 psi), it will cause the RE-6 valve to go into an mounted near the tanks. As circuit pressure increases,
“emergency mode”. This will apply the air pressure the RE-6 valve directs air to the pressure converters
stored in the (dry) air tanks (front and rear) to the which apply the brakes while air system pressure is
pressure converters. building. The service brakes will remain applied until
the pressure reaches approximately 7.0 kg/cm2 (100
To control truck speed without use of the service psi), at which point the exhaust valve of the RE-6 valve
brakes, the operator may use the hand operated con- will open and release the brakes.
trol valve lever to apply the rear wheel wet disc brakes.
This valve provides pressure to rear brakes only to
reduce truck speed. Use of only the rear brakes de- AIR TREADLE VALVE
creases the possibility of the truck skidding on slippery The brake circuit is controlled by a dual section treadle
roads. valve located on the floor of the cab. When the brake
For full braking power in an EMERGENCY situation, pedal is depressed, air pressure within the two sec-
the operator can manually apply the emergency brake. tions of the brake valve is directed to two separate
Located on the console next to the operator, the emer- brake circuits. One air circuit controls operation of a
gency brake toggle lever is to be used for emergency brake circuit for actuation of the two brake actuators,
application of the wheel brakes in an EMERGENCY both front and one rear brake assemblies. The other
ONLY. DO NOT use the emergency brake valve to circuit actuates the other two brake actuators. If one
stop the truck during normal operation! brake circuit should malfunction, the other circuit is still
available to apply the brakes. The flow of air from each
The parking brake toggle lever, mounted on the con- section of the dual brake valve passes through a valve
sole next to the operator, enables the operator to apply located in each circuit and then to the emergency relay
and release the parking brake. The parking brake is valves (RE-6) mounted on the front and rear dry tanks.
spring applied and air released. It should be used when The emergency relay valves regulate pressure from
parking the truck in a designated parking area. the dry air tanks to be applied to the pressure convert-
The Front Brake “OFF” switch changes the braking ers.
action of the system for operation under various road
surface conditions. The switch is located on the instru-
ment panel to the left of the steering wheel. When the
switch is in the “OFF” position (dry road conditions),
brake pressure is applied to both front and rear wheels.
If the switch is depressed to the “ON” position (slippery
road conditions), brake pressure is applied only to the
rear wheels. The pilot light inside the switch is illumi-
nated in this position.
J02023 11/98 Brake Circuit Operation J2-1

EMERGENCY RELAY (RE-6) VALVE
The emergency relay (RE-6) valves are piston type, air operated valves. The truck has four RE-6 valves located on
the dry air tank. The following illustrations describe the operation of the RE-6 valve.
FIGURE 2-1.
CHARGING-BRAKE APPLYING
Below 6.3 kg/cm2 (90 psi)
As system pressure builds, air enters the

emergency and air tank port. The air flow
within the valve is directed to the pressure
converters which apply the brakes while the
air system is building pressure.
FIGURE 2-2.
SYSTEM CHARGING
6.3 - 7.0 kg/cm2 (90 - 100 psi)
As air system pressure continues to build,

the inlet and exhaust valve is seated by the
downward movement of the emergency
piston caused by system pressure being
applied to the top of the emergency piston.
The air pressure is trapped in the RE-6
valve and the pressure converters.
J2-2 Brake Circuit Operation J02023 11/98

FIGURE 2-3.
BRAKE RELEASING
7.0 kg/cm2 (100 psi)
When air pressure reaches approximately

7.0 kg/cm2 (100 psi), the exhaust area of
the inlet and exhaust valve will open, re-
leasing all air pressure in the pressure con-
verters which in turn releases the brakes.
FIGURE 2-4.
SYSTEM CHARGED-VALVE STATIC
7.0 kg/cm2 (100 psi)
The emergency relay (RE-6) valves are in

a static condition when the air tank is fully
charged, the check valve is closed and the
inlet area of the inlet and exhaust valve is
seated against the emergency piston.

FIGURE 2-5.
BRAKE PEDAL APPLICATION
During normal brake application, regulated system air
pressure is metered from the service brake treadle
valve to the “Service” port of the RE-6 valve. As air
pressure enters the “Service” port, the relay piston is
forced downward closing the exhaust area of the inlet
and exhaust valve. Further downward movement of the
relay piston opens the inlet portion of the inlet and
exhaust valve. This allows graduated air pressure to
flow from the “Emergency” port line, through the check
valve, through the inlet area, and out the delivery ports
to the pressure converters. The pressure converters
then apply hydraulic pressure to the brake actuators.
The air flow is assisted by the volume of air stored in
the dry air tank which aids in a more rapid application
of the brakes.
FIGURE 2-6.
BRAKES APPLIED - VALVE BALANCED
When air pressure below the relay piston is equal to the
air pressure above it, the relay piston and emergency
piston will lift slightly and the inlet area of the inlet and
exhaust valve will close. The valve is then in a balanced
condition
NOTE: The brakes are not necessarily fully applied when
the valve is in a balanced position, but are applied only
to the extent of pressure applied by the operator at the
brake treadle valve. Should the operator continue to
depress the brake pedal, additional air pressure will open
the inlet passage in the RE-6 valve. Again the balanced
condition will occur if the operator stops and retains the
brake pedal in one position.
Releasing
When the operator releases the brake pedal, air in the
service port line is exhausted through the exhaust port of
the service brake valve. Upward movement of the relay
piston unseats the exhaust portion of the inlet and ex-
haust valve and air in the pressure converter is exhausted
through the RE-6 valves releasing the brakes.
FIGURE 2-7
FULL EMERGENCY
Whenever air pressure at the “Emergency” port drops
to 3.2 kg/cm2 (45 psi), the check valve in the RE-6 valve
closes and spring pressure lifts the emergency piston.
The inlet portion of the inlet and exhaust valve opens
and the exhaust portion closes, applying air tank pres-
sure out of the delivery ports to the pressure converters.
When air tank pressure equalizes the pressure at the
pressure converters, the RE-6 valve is in the full emer-
gency position.
FIGURE 2-7.

HAND BRAKE VALVE
(Retarder control valve)
The hand brake valve is an air valve for the retarder The air discharge pressure varies according to the
control, and is attached to the steering column. angle of the valve handle as it is rotated, providing
modulated retarder application.
FIGURE 2-8. HAND BRAKE VALVE
FIGURE 2-10. HAND BRAKE VALVE

COMPONENTS
1. Lock washer 9. Head

2. Cam follower 10. Ring
3. Cam 11. Spring
4. Cover 12. Piston
FIGURE 2-9. HAND BRAKE VALVE 5. Valve guide 13. Spring
6. Body 14. Valve
1. Clamp 3. Handle 5. Spring
7. Stem 15. Valve seat
2. Pin 4. Plunger
8. Spring

FUNCTION
Refer to Figure 2-11.
When the handle is placed in the “BRAKE” position,
then piston (5) will be pushed down by cam (1) through
spring (2).
The exhaust valve seat provided at piston (5) will be
pushed against exhaust valve (4) to close the valve.
The inlet valve (6) and exhaust valve (4) form one body
After the exhaust valve (4) is closed, inlet valve (6) is
opened. Compressed air is fed to the relay valve
through the inlet valve, actuating the rear brake cham-
ber cylinder and applying the retarder brake.
FIGURE 2-11.
Air balancing position with the spring force

(Figure 2-12):
When the air pressure imposed on the underside of

piston (5) balances with the force of spring (2), piston
(5) will be raised slightly, closing the inlet valve (6). In
this condition, the valve seat (3) remains closed, keep-
ing the air pressure at the relay valve constant.
In this manner, the brake valve is kept in a balanced
condition, holding the air pressure constant depending
on the position of the handle.
Brake releasing position (Figure 2-13): FIGURE 2-12.
When the handle (7) is moved to the brake “RE-

LEASE” position, the force of spring (2) will be re-
duced. Then, piston (5) will be raised by the air
pressure on the underside of the piston, causing the
exhaust valve to open, which will, in turn, cause the
pressurized air at the relay valve to flow out into the
atmosphere through the exhaust valve.
If the air pressure on the piston underside balances
with the force of spring (2), the exhaust valve will be
closed again to hold the balanced condition, and the
air pressure at the relay valve will be kept constant.
When the handle (7) is moved to the “COMPLETE
RELEASE” position, the force on spring (2) will be
removed causing piston (5) to be pushed up, which, in
turn, will cause all of the pressurized air to flow out into
the atmosphere. Thus, the brake will be completely
released.
FIGURE 2-13.

FIGURE 2-16. PARKING BRAKE PILOT VALVE
1. Piston 3. Seat A. To Atmosphere C. To Parking Brake Relay Valve
2. Valve Body 4. Seat B. From Emergency Brake Circuit D. From Rear Air Tank
PARKING BRAKE PILOT VALVE
FUNCTION
If the air for the emergency brake circuit is cut, the As a result, the parking brake is set to the “TRAVEL”
circuit between the parking brake valve and parking position.
relay valve is shut off and the parking brake is applied.
When no air is being sent to the emergency
OPERATION brake circuit ( Figure 2-16):
Piston (1) is moved up by the spring, the air from rear
When air is being sent to the emergency
air tank is shut off, and the air from the relay valve is
brake circuit (Figure 2-15):
released to the atmosphere, so the parking brake is
Piston (1) is moving down in the direction of the arrow, applied.
so the air from the rear air tank is sent to the relay valve.
FIGURE 2-14. PARK BRAKE RELEASED FIGURE 2-15. PARK BRAKE APPLIED

FIGURE 2-17. PARKING BRAKE RELAY VALVE
1. Cover 3. Body A. From Parking Brake Pilot Valve C. Exhaust Port
2. Relay Piston 4. Exhaust Cover B. From Air Tank D. To Parking Brake Chamber
PARKING BRAKE RELAY VALVE
FUNCTION
Parking brake valve in “PARKING” (Figure
Parking brake valve in “TRAVELING” (Figure 2-19):
2-18):
The pressurized air in the piston upper section (A) will
Pressurized air will enter (A), the upper section of the be exhausted through the parking brake valve, reduc-
relay piston, causing the piston to lower. Then, the ing the pressure in (A).
exhaust valve seat (1) will close the exhaust port (C)
and open the valve (2). Consequently, the relay piston will be pushed up by
the pressurized air in the section (B), causing the
If the valve is opened, the pressurized air will be fed to exhaust port to open. Thus, the air in the section (B)
the parking brake chamber through the valve. will be exhausted.
FIGURE 2-18. PARK BRAKE RELEASE FIGURE 2-19. PARK BRAKE APPLIED
1. Exhaust Valve Seat A. From Parking Brake Pilot Valve D. To Parking Brake
2. Valve B. Chamber Chamber
C. Exhaust Port E. From Air Tank

BRAKE CHAMBER
FIGURE 2-20. FRONT BRAKE CHAMBER

1. Piston 2. Push Rod 3. Air Cylinder 4. Breather 5. Master Cylinder 6. Piston
FRONT REAR
1. Air cylinder 1. Air cylinder
Ratio: 23.7:1 Ratio: 7.0:1
Fluid used: Air Fluid used: Air
Effective area: 314 cm2 (48.7 in.2) Effective area: 314 cm2 (48.7 in.2)
Stroke: 100 mm (3.94 in.) Stroke: 133.5 mm (5.26 in.)
Max. operating pressure: 9 kg/cm2 (128 PSI) Max. operating pressure: 9.5 kg/cm2 (135 PSI)
Normal operating pressure: 8.3 kg/cm2 (118 PSI) Normal operating pressure: 8.3 kg/cm2 (118 PSI)
2. Master cylinder 2. Master cylinder
Fluid used: Engine oil (SAE10W) Fluid used: Engine oil (SAE10W)
Effective area: 12.6 cm2 (1.95 in.2) Effective area: 50.2 cm2 (7.78 in.2)
Delivery oil quantity: 120 cc @ 97 mm (3.88 in.) Delivery oil quantity: 480 cc @ 97 mm (3.88 in.)
stroke stroke
Max. operating pressure: 207 kg/cm2 (2944 PSI) Max. operating pressure: 51 kg/cm2 (725 PSI)
Normal operating pressure: 200 kg/cm2 (2845 PSI) Normal operating pressure: 47 kg/cm2 (668 PSI)
FIGURE 2-21. REAR BRAKE CHAMBER

1. Air cylinder 4. Rod 7. Master Cylinder 10. Body
2. Air Piston 5. Breather 8. Bleeder Valve 11. Sensor
3. Spring 6. Piston 9. Piston Valve (Brake Line Failure)

FIGURE 2-22. SLACK ADJUSTER
1. Body 6. Spring A: To Brake Piston
2. Cylinder 7. Cap B: To Brake Piston
3. Piston 8. Valve C: From Brake
4. Spring 9. Seat Chamber
5. Cover 10. Bleeder
SLACK ADJUSTER Specifications

The slack adjuster is installed in the circuit between Replacement oil volume: 231.2 cc (14 in.3) each side
the brake chamber and brake piston. Effective area: 50.3 cm2 (7.80 in2)
Stroke: 46 mm (1.81 in.)
The slack adjuster controls the return stroke of the
brake piston (by controlling the amount of return oil), Normal pressure: 53 kg/cm2 (754 PSI)
and provides a movement with a constant time lag for Max. available pressure: 65 kg/cm2 (925 PSI)
the brakes, regardless of whether the disc brakes are
new or worn.

FUNCTION
When brake pedal is depressed (Figure 2-23):

The oil discharged from the brake converter flows into
each cylinder (Port B), causing piston (2) to move by
stroke d1. Thereby, the oil equivalent to stroke d1 flows
out Port A to the brake piston. At this time, no clearance
exists between the brake piston and discs, and the
braking force does not occur.
FIGURE 2-23. BRAKE PEDAL DEPRESSED

Adjuster function (Figure 2-24):
A. To Brake Piston B. From Converter
Brake apply
When the brake pedal is depressed, oil in a volume
equal to stroke d2 will be discharged out Port A by
piston (2). When the oil pressure in the slack adjuster
exceeds the pressure limit of poppet valve (1), it opens
allowing the pressure oil to flow out Port A. Thereby,
the oil pressure is imposed on the brake piston, creat-
ing the braking force.
When the brake piston volume is larger than the

slack adjuster piston volume.
The oil equal to the shortage in the brake piston volume
will be supplied through poppet valve (1) and out Port
A, creating pressure in the brake piston chamber.
Consequently, the braking effect will be the same as
when the brake piston volume and the adjuster volume
FIGURE 2-24. ADJUSTER FUNCTION
are equal.
When brake pedal is released (Figure 2-25):

When the brake is released, the back pressure is
imposed on the brake piston by the brake cooling oil
pressure, causing a returning pressure to occur be-
tween the adjuster and the brake chamber. Thereby,
the piston (1) is moved back by stroke d3 and the
clearance between the disc and the brake piston is
kept at a dimension equivalent to the adjuster volume.
FIGURE 2-25. BRAKE PEDAL RELEASED

PRESSURE SWITCH
FUNCTION
Indicates low air pressure below 75psi. Turns on dash
light and warning buzzer.
If compressed air at a pressure higher than the speci-
fied pressure is applied to piston cup (7), the piston
cup is pushed up, and at the same time, contact disc
(4) is also pushed up.
When this happens, contact plate (8) and contact disc
(4) are separated, so the circuit is opened.
Specifications:
• Normally closed switch, opens at 75psi.
• Measuring between pins 1 and 2 at:
8.3 kg/cm2 (120 psi) - 160 ohms or less
5.2 kg/cm2 (75 psi) - 640 - 800 ohms
FIGURE 2-26. PRESSURE SWITCH
1. Cover 5. Gasket
2. Contact Plate 6. Body
3. Spring 7. Piston Cup
4. Contact Disc 8. Contact Plate
STOP LIGHT SWITCH
FUNCTION
When the brake pedal is depressed, air pressure acts
on the switch to light up the stop lights.
Specifications:
Service brake switch
• Measuring between pins 1 and 2
above 0.6 kg/cm2 (8 psi) continuity
below 0.2 kg/cm2 (3 psi) no continuity
Emergency Brake Switch

above 4.9 kg/cm2 (70 psi) no continuity
below 3.7 kg/cm2 (53 psi) continuity
FIGURE 2-27. STOP LIGHT SWITCH
1. Terminal 5. Block
2. Terminal 6. Diaphragm
3. Spring 7. Body
4. Plate

PARKING BRAKE SWITCH
FUNCTION
If the parking brake is released, the compressed air
from the air tank acts on the diaphragm, and closes
the contacts of the switch.
Specifications: FIGURE 2-28. PARKING BRAKE SWITCH

Normally open switch: closes at 5.2 kg/cm2 (75 psi), 1. Port 3. Cover
opens at 4.2 kg/cm2 (60 psi). 2. Diaphragm 4. Connector
above 5.7 kg/cm2 (80 psi) continuity
below 3.7 kg/cm2 (53 psi) no continuity
AUTOMATIC RETARDER VALVE
FUNCTION
The input port and output port are connected by pass-
ing electricity through the coil of the solenoid valve.
When this happens, the auto retarder is applied.
Specifications:
Normally closed switch, actuates at 2500 ±10 RPM.
Opens and releases retarder at 2350 ±10 RPM.
• Measuring between pins 1 and 2, 20-60 ohms.
FIGURE 2-29. AUTOMATIC RETARDER VALVE
1. Core 8. Spring
2. Coil Assembly 9. Body
3. Spring 10. Connector
4. Plunger
5. Valve Seat A: Input Port
6. Rod B: Output
7. Valve C: Exhaust Port

FRONT BRAKE CUT-OFF VALVE
Function
This valve is installed in the pilot circuit between the
brake valve and RE-6 valve. It is used to cancel the
actuation of the front brake according to the haul road
conditions .
When the Front Brake Off switch in the operator’s
compartment is pressed, current flows in the coil of the
solenoid valve, and the solenoid valve is actuated.
When this happens, the circuit from the brake valve to
the front brake RE-6 valves is shut off, and the front
brakes are released, if applied.
Specifications:
• Measuring between pins 1 and 2, 20-60 ohms.
FIGURE 2-30. FRONT BRAKE CUT-OFF VALVE

1. Coil Cover 9. Valve
2. Plunger 10. Spring
3. Coil Assembly
4. Core
5. Rod A: Inlet Port
6. Body B: Outlet Port
7. Connector C: Exhaust Port
8. Valve Body

BRAKE COOLING VALVE (BCV)
When the retarder is not being used, this valve by-
passes part of the brake cooling oil to reduce the power
loss when traveling. The main valve spool is actuated
by switching the solenoid valve ON or OFF.
If any abnormal pressure is generated in the hydraulic
circuit, the pilot relief valve is actuated, and this actu-
ates the main relief valve, so the brake cooling valve
also acts as an unloader valve.
FIGURE 2-32. SCHEMATIC
1. Main Valve Spool A: Pilot Port

2. Pilot Relief Valve B: Pilot Port
9.0 kg.cm2 (128 psi) C: Main Return To Tank
3. Solenoid Valve D: Pilot Port
E: From Pump FIGURE 2-31. BRAKE COOLING VALVE
F: To Tank
1. Pilot Relief Valve A: Pilot Port
9.0 kg.cm2 (128 psi) B: Pilot Port
2. Valve Body C: Main Return To Tank
3. Solenoid Valve D: Pilot Port
4. Main Valve Spool E: From Pump
5. Restrictor Plate F: To Tank

2-WAY AIR CONTROL VALVE Function
(parking Brake Valve, Emergency Brake Valve) Pressurize Work Port (Brake Release)
A 2-way control valve is used as the parking brake Turning the lever (5) to the “TRAVELING” position will
valve or emergency brake valve. When the valve is cause the valve (4) to be pushed down by the plunger
used as a parking brake valve, the parking brake can (2), which will in turn, furnish pressurized air to the
be applied or released by turning the lever to PARK- parking brake cylinder.
ING or TRAVELING position. When the valve is used In the emergency brake, the pressurized air is supplied
as an emergency brake valve, the emergency brake to an emergency port of the RE-6 valves (front and
can be applied or released by turning the switch to rear).
BRAKING or TRAVELING position.
FIGURE 2-34. AIR VALVE

1. Body A: Exhaust Port FIGURE 2-33. BRAKE RELEASE
2. Plunger B: Outlet Port
3. Spring 1. Body A: Exhaust Port
C: Inlet Port
4. Valve 2. Plunger B: Outlet Port
5. Lever 3. Spring C: Inlet Port
6. Pin 4. Valve
7. Valve Spring 5. Lever
8. O-Ring 6. Pin
7. Valve Spring

Discharge Work Port (Brake Apply)
Turning the lever (5) to the “PARKING” or “BRAKING”
position will cause the plunger (2) to be returned
upward by the spring (3). Then, the valve (4) will be in
the seat in body (1), letting the plunger (2) come off the
valve (4). Thereby, the pressurized air in the parking
brake control line is exhausted through a small center
orifice in the plunger (2).
After exhausting air from the spring cylinder, parking
brake is actuated by spring force. In the emergency
brake, the pressurized air in the emergency port line
of the RE-6 valves is purged out through a central
orifice in plunger (2). If the air pressure at an emer-
gency port in the RE-6 valves drops, the RE-6 will
actuate, causing the brakes to apply.
FIGURE 2-35. BRAKE APPLY
1. Body A: Exhaust Port

2. Plunger B: Outlet Port
3. Spring C: Inlet Port
4. Valve
5. Lever
6. Pin
7. Valve Spring

BRAKE VALVE
FIGURE 2-36. BRAKE VALVE
1. Plunger 7. Upper valve (upper inlet valve) 13. Lower valve return spring
2. Seat 8. Outer relay piston 14. Relay piston return spring
3. Pedal 9. Lower valve (lower inlet valve) 15. Upper ring retainer
4. Piston 10. Cover 16. Upper valve return spring
5. Stop bolt 11. Lower valve guide 17. Valve body
6. Piston return spring 12. Check valve 18. Rubber Spring

FUNCTION If the upper inlet valve (7) is opened, the pressurized
air will flow to the relay piston (8) through passage (F),
A. When brake pedal is being depressed.
pushing inner relay piston (8) downward, which, in
When the brake pedal (3) is depressed, the pedal turn, will open the lower inlet valve (9).
movement will be transmitted to the piston (4) through
Then, pressurized air from the air tank will flow to the
the rubber spring (18), causing the piston (4) to move
front brake relay valve to start applying the front brake.
downward. Then, the exhaust port (E) will be closed
and the upper inlet valve (7) will be opened. Thus, the Actually, the force required to move the relay piston (8)
pressurized air from the air reservoir (tank) will flow to is very small and, therefore, there is little difference in
the rear brake chamber, causing the application of the timing for the upper and lower inlet valves to begin
rear brake to start. opening.
FIGURE 2-37. BRAKE APPLY
A: From Air Tank

B: From Air Tank
C: To Relay Valve
D: To Relay Valve
E: Exhaust Port
F: Passage
G: Exhaust Port
3. Brake Pedal
4. Piston
7. Upper Inlet Valve
8. Relay Piston
9. Lower Inlet Valve
17. Inner Relay Piston
18. Rubber Spring

B. When air pressure and spring force are If the upper and lower air pressure values on the relay
balanced piston (8) are equal to each other, the piston return
spring (14) will move the relay piston (8) slightly up-
(When the brake pedal (3) is depressed to and held at
ward, and the lower inlet valve (9) will be closed by the
a certain point on its stroke.)
action of spring (13). However, the exhaust port (G)
If the air pressure in the brake chamber acting on the remains closed and the air acting on the front relay
lower part of piston (4) is equal to the force of the valve cannot escape, thus the front braking force is
rubber spring (18) pushing piston (4) downward, the kept constant.
upper inlet valve (7) will close, stopping the flow of
If pedal (3) is depressed to the end of its stroke, the
pressurized air from the reservoir to the brake cham-
upper and lower inlet valves (7) and (9) will remain
ber. The exhaust port (E) remains closed. Then, the
opened, equalizing the air pressure in the brake cham-
air pressure in the brake chamber will be kept constant
ber with that in the air tank.
and consequently, the braking force will be maintained
at the same value.
FIGURE 2-38. BRAKE BALANCE
A: From Air Tank

B: From Air Tank
C: To/From Relay Valve
D: To/From Relay Valve
E: Exhaust Port
F: Passage
G: Exhaust Port
3. Brake Pedal
4. Piston
7. Upper Inlet Valve
8. Relay Piston
9. Lower Inlet Valve
13. Spring
14. Spring
18. Rubber Spring

C. When the brake is released
When the effort depressing pedal (3) is reduced, the
force on the upper part of piston (4) will eliminated, and
piston (4) will be pushed up by the air pressure and
spring force acting on its lower part. Exhaust port (E)
will be opened, to allow escape of the pressurized air
in the brake chamber into the atmosphere. As a result,
the force actuating the rear brake will be reduced.
Consequently, the air pressure acting on the upper
part of relay piston (8) will also be reduced. Since relay
piston (8) is also pushed up by the air pressure and
spring force acting on its lower part, the exhaust port
(G) will be opened. Then, the pressure at the relay
valve actuating the front brake will be reduced, causing
release of the front brakes.
FIGURE 2-39. BRAKE RELEASE
A: From Tank
B: From Tank
C: From Relay Valve
D: From Relay Valve
E: Exhaust Port
F: Package
G: Exhaust Port
3. Brake Pedal
4. Piston
8. Relay Piston

NOTES

BRAKE CIRCUIT COMPONENT SERVICE
BRAKE TREADLE ASSEMBLY
Removal
1. Depress brake pedal several times to bleed air
from air tank.
2. Remove cover from below pedal assemblies.
3. Disconnect lines (1, Figure 3-1) between air tank
and brake valve at valve end.
4. Disconnect lines (2) between relay valve and
brake valve at valve end.
6. Remove pin (2), then remove brake pedal (3).
FIGURE 3-2. BRAKE TREADLE
7. Remove 3 mounting capscrews (2, Figure 3-3),
then leave mounting plate (1), and remove brake 1. Cover 3. Brake Pedal
valve assembly (3, Figure 3-1) from below. 2. Pin
Installation 5. Connect air system lines (2, Figure 3-1) between

relay valve and brake valve.
1. Install brake valve assembly (3, Figure 3-1) to Tighten sleeve nuts to 1.1 ±0.1 kg.m (8 ± 1 ft.lb.)
plate (1, Figure 3-3). torque.
2. Install brake pedal (3, Figure 3-2). NOTE: Operate air system and check that there is no
3. Install cover (1). air leakage.
4. Connect lines (1, Figure 3-1) between air tank and 6. Install cover below pedal assemblies.
brake valve.
FIGURE 3-1. BRAKE TREADLE LINES

FIGURE 3-3. BRAKE TREADLE
1. Air Inlet Lines 3. Brake Valve Assembly
2. Air System Lines 1. Mounting Plate 2. Mounting Capscrews
J03021 11/98 Brake Circuit Component Service J3-1

Disassembly
1. Push piston assembly (1, Figure 3-4) and remove
retainer (2).
2. Remove piston assembly (1, Figure 3-5) and
remove spring (2).
FIGURE 3-6. LOWER COVER ASSEMBLY

1. Lower Cover 2. Spring
3. Remove mounting bolts, then remove lower cover

assembly (1, Figure 3-6).
4. Remove spring (2).
5. Pull out inner relay piston (1, Figure 3-7) from
body.
NOTE: Be careful not to damage the sliding surface of
the piston.
FIGURE 3-4. RETAINER

6. Pull out outer relay piston (2) from body.
1. Piston Assembly 2. Retainer
NOTE: Be careful not to damage the sliding surface of
the piston.
FIGURE 3-5. PISTON ASSEMBLY FIGURE 3-7. INNER RELAY PISTON
1. Piston Assembly 2. Spring 1. Inner Relay Piston 2. Outer Relay Piston
J3-2 Brake Circuit Component Service J03021 11/98

FIGURE 3-8. SNAP RING FIGURE 3-10. LOWER VALVE AND CHECK VALVE
1. Snap Ring 1. Snap Ring 5. Spring

2. Housing
2. Check Valve Assem- 6. Lower Valve
bly
7. Cover
3. Snap Ring
4. Guide
7. Remove snap ring (1, Figure 3-8).

8. Pull out upper valve assembly from body (1, Assembly
Figure 3-9), and remove snap ring (2), then re- 1. Assemble spring (5, Figure 3-10) and guide (4) in
move washer (3), retainer (4), spring (5), and lower valve (6), assemble snap ring (3), then
upper valve (6). assemble in cover (7).
9. Remove snap ring (1, Figure 3-10), then remove 2. Assemble check valve assembly (2) in cover, then
check valve assembly (2) from cover (7). assemble snap ring (1).
10. Remove snap ring (3), and disassemble into guide NOTE: Assemble the O-ring (2 types) to the retainer.
(4), spring (5), and lower valve (6).
3. Assemble spring (5, Figure 3-9), retainer (4), and
washer (3) in upper valve (6), then assemble snap
ring (2) and assemble in body (1).
4. Assemble snap ring (1, Figure 3-8).
5. Fit O-ring to sliding portion, and assemble outer
relay piston (2, Figure 3-7) in body.
6. Fit O-ring- to sliding portion, and assemble inner
relay piston (1) in body.
7. Assemble spring (2, Figure 3-6) in inner relay
piston. Fit O-ring to mount and install lower cover
assembly (1) to body.
8. Assemble spring (2, Figure 3-5) in body.
9. Assemble piston assembly (1).
FIGURE 3-9. UPPER VALVE
10. Push piston assembly (1, Figure 3-4) and com-
1. Body 4. Retainer press spring, then install retainer (2).
2. Snap Ring 5. Spring
3. Washer 6. Upper Valve

FRONT BRAKE CHAMBER ASSEMBLY
Removal Disassembly
NOTE: Before disassembling, make match marks at

all joints to act as a guide when reassembling.
Open the drain valve to release the air inside the
tank.
1. Remove 4 capscrews (1, Figure 3-13), then re-
1. Disconnect air lines (1, Figure 3-11). move oil cylinder (2).
2. Remove brake oil lines (2). 2. Supply compressed air at 1-2 kg/cm2 (14-28 psi)
3. Remove front brake chamber assembly (3). to air cylinder, and push out rod (4) of piston and
rod assembly (3) fully.
NOTE: When brake oil tubes (2) are removed, the oil
a. Remove ring (2, Figure 3-14) from ring groove,
in the brake oil tank will flow out, so fit plugs.
then move towards push rod, and pull out pin
(1).
b. When pin (1) is pulled out, it is possible to
remove oil piston (5, Figure 3-15), bushing
guide (4), and ring (2).
c. After removing oil piston, exhaust compressed
air from air cylinder (1).
3. Remove seal (10, Figure 3-13) and backup ring
(11) from oil piston assembly.
FIGURE 3-11. FRONT BRAKE CHAMBERS

1. Air Lines 3. Front Brake Chambers
2. Oil Lines
Installation
NOTE: When installing the brake chamber assembly,
be certain that the spacers support the chamber away
from the mounting plate. If the chamber is installed
touching the mounting plate, the chamber may crack FIGURE 3-12. OIL CYLINDER
when the mounting capscrews are tightened.
1. Capscrews 2. Oil Cylinder
1. Install front brake chamber assembly (3).

2. Connect brake oil lines (2).
3. Connect air lines (1).

FIGURE 3-13. FRONT BRAKE CHAMBER
1. Capscrews 7. Oil Piston 13. Spring 19. Spacer

2. Oil Cylinder 8. Bushing Guide 14. Cover Assembly 20. Bushing
3. Rod (complete) 9. Air Cylinder 15. Packing 21. Filter
4. Rod 10. Seal 16. Stop Ring 22. Ring
5. Ring 11. Backup Ring 17. Cup Support 23. Plug
6. Pin 12. Capscrews 18. Secondary Cup 24. Mounting Spacer
FIGURE 3-14. BRAKE CHAMBER FIGURE 3-15. OIL PISTON

1. Pin 2. Ring 3. Rod 1. Air Cylinder 3. Pin 5. Oil Piston
2. Ring 4. Bushing Guide

The spring has a reaction force of 65 kg (143 lbs.)
when compressed approximately 100 mm (3.9 in),
so be extremely careful when loosening the cap-
screws.
NOTE: Check that there is no compressed air inside

the air cylinder.
FIGURE 3-17. AIR CYLINDER COVER

When removing capscrews (12, Figure 3-13), it is
safer if 2 or 3 fully threaded capscrews (1, Figure 1. Cup Support 4. Spacer
3-16) with a length of approximately 150 mm (5.9 2. Secondary Cup 5. Stop Ring
in) long are used as a loosening tool. 3. Cover Assembly
4. Replace two or three capscrews (12, Figure 3-13)

6. Remove stop ring (5, Figure 3-17 or 3-18) with
with two or three fully threaded capscrews (1,
flat-headed screwdriver, then remove cup sup-
Figure 3-16) of approximately 150 mm (5.9 in)
port (1), secondary cup (2), spacer (4), secondary
long to use as a tool. Loosen and then remove
cup (2), and cup support (1) in order.
remaining capscrews (12, Figure 3-13), then re-
move air cylinder (5, Figure 3-16), piston and rod 7. Carefully push bushing (7, Figure 3-18) in, then
assembly (3), and spring (4) from cover assembly pull out and remove.
(2).
8. Remove snap ring (8), then remove filter (9).
5. Remove packing (15, Figure 3-13) from piston and
9. Remove plug (6).
rod assembly (3).
FIGURE 3-18. AIR CYLINDER COVER

1. Cup Support 6. Plug
2. Secondary Cup 7. Bushing
FIGURE 3-16. AIR CYLINDER 3. Cover Assembly 8. Snap Ring
4. Spacer 9. Filter
1. Capscrews 4. Spring 5. Stop Ring
2. Cover Assembly 5. Air Cylinder
3. Rod (Complete)

ASSEMBLY Oil piston assembly
NOTE: Assemble all components with line up marks 1. Supply compressed air at 1-2 kg/cm2 (14-18 psi)
made during disassembly. to air cylinder (9, Figure 3-13), and extend piston
and rod assembly (3) fully.
Coat the outside diameter of air piston rod (4, Figure
3-13), the cup groove, cup (14) and air cylinder (9), and 2. Install backup ring (11) and seal (10) to oil piston
the inside diameter (sliding part) with a suitable (7).
amount of lithium grease.
3. After moving ring (2, Figure 3-14) towards air
Coat the outside diameter of oil piston (7), the cup chamber end, secure bushing guide (4, Figure
groove, cup (10), the inside diameter of oil cylinder (2), 3-15) and oil piston (5) to oil piston with mounting
and the inside diameter (cup groove) of cover (14), and pin (3), then install ring (2) to ring groove.
2 cups (18) with a suitable amount of brake system oil.
4. Exhaust compressed air from air cylinder.
Cover assembly
Oil cylinder
1. Install plug (6, Figure 3-18) with Three Bond
1. Install oil cylinder (2, Figure 3-12) to air cylinder
(TB2411) adhesive and tighten to 2.0 kg.m (14
assembly.
ft.lbs.) torque.
2. Tighten capscrews (1) to 3.85 kg.m (28 ft. lbs.)
2. Install filter (9) and snap ring (8).
torque.
3. Assemble bushing (7), secondary cup (2, Figure
3-17 or 3-18), spacer (4), secondary cup (2), cup
support (1) and stop ring (5) in order.
Checking
1. Bleed air from oil cylinder.
Air cylinder assembly 2. Check that at least 180 kg/cm2 (1680 psi) of oil
pressure is generated in the oil cylinder when 8
1. Install packing (15, Figure 3-13) to piston and rod
kg/cm2 (114 psi) of air pressure is applied to air
assembly (3).
cylinder.
3. Check that there is no leakage of air or oil.
Use 2 or 3 fully threaded capscrews (1, Figure 3-16)

with a length below the head of approximately 150
mm (5.9 in.), compress spring (4) uniformly and
tighten to install the original capscrews (12, Figure
3-13).
2. Use 2 or 3 fully threaded capscrews (1, Figure

3-16) with a length of approximately 150 mm (5.9
in.) to assemble the air cylinder.
3. Assemble spring (4, Figure 3-16), piston and rod
assembly (3), O-ring, and air cylinder (5) to cover
assembly (2).
4. Apply Three Bond (TB1374) thread tightener to
the six capscrews (12, Figure 3-13) and tighten
capscrews to 6.7 kg.m (48 ft.lbs.) torque.

REAR BRAKE CHAMBER ASSEMBLY
REMOVAL
1. Open the drain valve to release the air inside the
tank.
2. Disconnect air lines (1, Figure 3-19).
3. Remove brake oil hoses (2 & 3, Figure 3-20).
4. Remove the four capscrews from the chamber
moutning plate and remove rear brake chamber
assembly (1) from the truck.
FIGURE 3-20. REAR BRAKE CHAMBERS

1. Brake Chamber 3. Oil Hoses
2. Oil Hoses
INSTALLATION
Carry out installation in the reverse order to removal.
FIGURE 3-19. REAR BRAKE CHAMBERS

1. Air Lines 2. Oil Hoses

DISASSEMBLY
Oil cylinder and piston

1. Loosen large nut (14, Figure 3-21) and unscrew 4. Remove snap ring (26) from ring groove, and
oil cylinder (18) from air cylinder cover (9). move towards rod end, then pull out pin (24) and
remove oil piston (15) and ring (29).
2. Remove o-ring (25), cap (19), and bleeder (20)
from oil cylinder (18). 5. After removing oil piston (18), exhaust com-
pressed air from air cylinder (1).
3. Supply compressed air at 1-2 kg/cm2 (14-28 psi)
to air cylinder (1) and extend rod (34) of piston 6. Remove spring (21), ring (22), seat (23), valve
and complete rod assembly (2) fully. (16), ring (27), packing (28), and ring (29) from oil
piston.
FIGURE 3-21. REAR BRAKE CHAMBER
1. Air Cylinder 9. Cover 17. Packing 25. O-Ring 33. Rod

2. Piston 10. O-Ring 18. Oil Cylinder 26. Snap Ring 34. Rod
3. Packing 11. Mounting Plate 19. Cap 27. Ring 35. Washer
4. Ring 12. Breather 20. Bleeder 28. Packing 36. Ring
5. Spring 13. Packing 21. Spring 29. Ring 37. Washer
6. Caution Plate 14. Nut 22. Ring 30. Ring 38. Nut
7. Ring 15. Piston 23. Seat 31. O-ring 39. Sensor
8. Ring 16. Valve 24. Pin 32. Bolt

Air cylinder
The spring has a reaction force of 65 kg (143 lbs.)

when compressed approximately 100 mm (3.9 in),
so be extremely careful when loosening the cap-
screws.
Check that there is no compressed air inside air
cylinder.
FIGURE 3-23. PISTON AND ROD

When loosening capscrews (32, Figure 3-21), use
2 or 3 fully threaded bolts (1, Figure 3-22) with a 1. Packing 3. Nut
length below the head of approximately 150 mm 2. Ring 4. Washer
(5.9 in) long as a loosening tool.
3. Remove nut (3) and washer (4) and separate rod

1. Loosen six capscrews (32, Figure 3-21), then from piston.
replace two or three capscrews with capscrews
4. Remove ring (36, Figure 3-21) from rod.
that are 150 mm (5.9 in) long as shown in Figure
3-22. Remove air cylinder (1, Figure 3-21), piston
and rod assembly (2), and spring (5) from cover
assembly (9).
2. Remove packing (1, Figure 3-23) and ring (2) from
piston and rod assembly.
Cover assembly
1. Remove o-ring (10, Figure 3-21) from cover (9).
2. Remove ring (30), o-ring (31), and rod (33) from
cover.
3. Remove breather (12) from cover.
FIGURE 3-22. AIR CYLINDER
1. Capscrews 2. Cover
150 mm (5.9 in)

ASSEMBLY
NOTE: Coat the inside diameter (sliding part) of the air
Oil piston and cylinder assembly
cylinder, the outside diameter of the air piston and the
groove, the packing, and the inner face of the bushing 1. Assemble ring (29, Figure 3-21), packing (28), ring
built into the end cover with a suitable amount of lithium (27), valve (16), seat (23), ring (22), and spring
grease. (21) to oil piston (15).
NOTE: Coat the inside diameter of the oil cylinder, the 2. Supply compressed air at 1-2 kg/cm2 (14-28 psi)
outside diameter of the oil piston and the seal groove, to air cylinder assembly (1), and extend rod (34)
the outside diameter of the valve, and the seal parts fully.
with a suitable amount of engine oil (SAE10W).
3. Assemble oil piston assembly (15) to rod (34) and
insert pin (24).
Cover assembly
4. Exhaust compressed air from air cylinder.
1. Assemble packing (13, Figure 3-21), o-ring (10),
ring (8), and ring (7) into cover (9). 5. Install bleeder (20) and cap (19) into oil cylinder
(18). Tighten bleeder to 6.86 - 11.80 Nm (5 - 9 ft.
2. Assemble o-ring (31) to rod (33) and insert into
lbs.) torque.
cover (9). Install ring (30).
6. Assemble oil cylinder (18) and nut (14) to air
3. Install breather (12) into cover (9).
cylinder (1). Align bleeder (20) with breather (12)
so that the offset angle of the centerlines is no
more than 10o maximum offset. Tighten nut (14)
Air cylinder to 108 - 167 Nm (80 - 123 ft. lbs.).
1. Assemble ring (36, Figure 3-21) over rod (34).
2. Seat rod (34) into piston (2). Assemble washer
Checking
(37) and nut (38) to rod end. Tighten nut to 118 -
157 Nm (87- 116 ft. lbs.) torque. 1. Bleed air from oil cylinder.
3. Assemble packing (3) and ring (4) to piston (2). 2. Pistons must move full stroke at air pressure of 1
kg/cm2 (14 psi).
4. Assemble spring (5) and piston rod assembly (3)
into housing (1). 3. There must be no air leakage from any part at air
pressure of 8 kg/cm2 (114 psi).
5. Using capscrews (1, Figure 3-22), install cover
assembly (9, Figure 3-21) to air cylinder assembly
(1). Apply Three Bond TB1374 thread tightener
to capscrews (32) and tighten to 37.3 - 49.0 Nm
(28 - 36 ft. lbs.) torque.

SLACK ADJUSTER
Removal
1. Disconnect all hydraulic lines (1, Figure 3-24).
Cap all open lines to prevent contamination of

components.
2. Remove capscrews (2) and then remove slack

adjuster assembly.
3. Cap all open lines to prevent contamination of
components. FIGURE 3-24. SLACK ADJUSTER
1. Hydraulic Lines 2. Capscrew
Installation
1. Install slack adjuster assembly with capscrews (2, Slack Adjuster Assembly
Figure 3-24). Tighten capscrews to 18.0 ±1.5
kg.m (130 ±10 ft. lbs.) torque.
2. Connect all hydraulic lines (1). When assembling, check carefully that there is no
3. Bleed the air from the brake circuit. dirt, dust or chips on the inside surface of the
Refer to Section "J", "Brake Bleeding". adjuster.
1. Coat the inside surface of the cylinder housing (2,

Slack Adjuster Disassembly Figure 3-25/26) and all other sliding parts with
1. Remove capscrews (15, Figure 3-25/26), then clean brake system oil.
remove cylinder housings (2). Remove springs 2. If removed, install valve seat (3, Figure 3-25/26).
(13) and pistons (11). Install complete valve assembly (5 thru 8). Coat
2. Remove and discard O-rings (14). spring (8) with a lithium grease.
3. Remove seal assemblies (12) from pistons (11). 3. Tighten valve body (6B) to 6.0 ±0.5 kgm (45 ±4
Discard seal assemblies (12). ft. lbs.) torque. Install cover (9) and secure with
spring retainer ring (10).
4. Remove spring retainer ring (10) and cover (9).
4. Install seal assemblies (12) on pistons (11).
5. Remove complete valve assembly (5 thru 8).
Remove valve seat (3). Wash all parts thoroughly 5. Install piston/seal assembly into housing (2).
in clean solvent and inspect for nicks, scratches,
6. Install new O-rings (14) to body (1) and assemble
and excessive wear (especially at valve seats).
springs (13) into cylinder housing (2).
NOTE: If damage in found in this valve or in the
7. Install cylinder housing/spring to body (1). Secure
housing (2), it must be replaced as an assembly.
cylinder assemblies with capscrews (15) and
Washers (16).
8. Tighten capscrews (15) to 17.5 ±1.5 kgm (127
±10 ft. lbs.) torque.

FIGURE 3-25. SLACK ADJUSTER - CROSS-SECTION VIEW
1. Body 6A. Valve 10. Ring, Spring Retainer 15. Capscrew

2. Cylinder Housing 6B. Valve Body 11. Piston 16. Washer
3. Valve Seat 7. O-Ring 12. Seal Assembly
4. Plug 8. Spring 13. Spring
5. O-Ring 9. Cover 14. O-Ring
DIMENSION "C"
Standard Size Tolerance Standard Clearance
Clearance Limit
Clearance between Piston Housing
80 mm
Cylionder Housing -0.030 to -0.076 mm +0.074 mm 0.03 - 0.15 mm 0.25 mm
(3.15 in.)
and Piston (-0.001 to -0.003 in. (+0.003 in.) (0.001 - 0.006 in.) (0.098 in.)
TORQUE VALUES
6B. Tighten to 6.0 ±0.5 kgm (45 ±4 ft. lbs.) torque.
15. Tighten to 17.5 ±1.5 kgm (127 ±10 ft. lbs.) torque.

FIGURE 3-26. SLACK ADJUSTER - EXPLODED VIEW
1. Body 6A. Valve 10. Ring, Spring Retainer 15. Capscrew

2. Cylinder Housing 6B. Valve Body 11. Piston 16. Washer
3. Valve Seat 7. O-Ring 12. Seal Assembly 17. Bleeder Valve
4. Plug 8. Spring 13. Spring 18. Cap
5. O-Ring 9. Cover 14. O-Ring

BRAKE CIRCUIT CHECKOUT AND ADJUSTMENT
CHECKINGFRONT BRAKE PAD WEAR
NOTE: This check is nominally specified for every 500

hours of truck operation. If truck is operated in a ver
abrasive environment (i.e. sandy conditions), perform
this check every 250 hours of truck operation, or more
frequently, if conditions require it.
1. Stop the machine on level ground, apply th
parking brake, and put blocks under the tires.
2. Remove any dirt/mud accumulation from all pads,
calipers, and discs.
3. Check disc pad (1, Figure 4-6) visually, and if the
pad has reached the wear limit line (2) or if disc
material thickness is less than 3 mm (0.12 in.),
replace the pad.
The pad wear may not be the same for both left
and right wheels, so check the wear of all pads.
If any pad is worn beyond the limits stated above,
replace all pads (both left and right sides). FIGURE 4-1. FRONT PAD WEAR
Refer to "Front Brakes" Section for specific repair,
disassembly, or replacement procedures for th 1. Brake Pad 2. Wear Limit Line
front brake assembly.
Do not continue to use pads worn beyond limits.

Worn pads may result in inadequate braking
power.
TESTING BRAKE PRESSURE
2
1. Raise the air pressure to 8.3 kg/cm (118 psi)
pressure.
2. Remove the top air bleed plug (1, Figure 4-2) and
2
install a 400 kg/cm (5690 psi) pressure gauge.
3. Measure the hydraulic pressure when the brak
pedal is depressed. Minimum pressure should b
2
187 kg/cm (2660 psi).
4. Remove gauge and install plug. Refer to “Brak
FIGURE 4-2. FRONT BRAKE PRESSURE
Bleeding”, this section and bleed air from th
calipers.
1. Air Bleed Plugs 2. Brake Lin
J04009 11/ Brake Circuit Checkout and Adjustment J4-1

CHECKING WEAR OF REAR BRAKE
DISCS
Operational complaints can be expected when wea 5. After measuring the disc wear, remove wear gauge
increases abruptly or the wear on one side is extremely and install the air bleed plug, and bleed the air.
large.
6. Refer to “Brake Bleeding”, this section and bleed
air from the system.
Carry out inspection ONLY when the brake oil

temperature is below 60°C (140 °F).
1. Stop truck on level ground, apply parking brak

lever to the PARKING position, check that th
other brakes are not applied, then stop engine.
Put wheel chocks in front and behind tires to
prevent truck movement.
2. Remove air bleed plug (1, Figure 4-3) of the rear
brake, and install disc wear measurement gauge
as shown in Figure 4-4.
NOTE: Part number of wear gauge: 561-98-61120.
3. Turn keyswitch to “ON”, and check that air pres-

sure gauge indicates in “green” range. If air pres- FIGURE 4-3. REAR BRAKE WEAR
sure is low, run the engine at 2000 RPM until th
air pressure gauge indicates in the “green” rang 1. Air Bleed Plug 2. Brake Housing
2
[8.3 kg/cm (118 psi)]. Turn keyswitch to “OFF
to stop engine.
4. At this time, pull retarder control lever to full stroke.
Push the wear gauge in until it contacts the piston,
then check the position of the stamped mark on
the rod. (See illustration.)
NOTE: When the retarder control lever is pulled,
the wear rod will push out under hydraulic pres -
sure; be sure to support it when carrying out this
operation.
• If the stamped mark on the rod goes in beyond

the end face of the case, the discs have reache
their service wear limit.
Refer to "Rear Brakes" Section for specific
repair, disassembly, or replacement proce -
dures for the rear brake assembly
• If the stamped mark on the rod does NOT go

FIGURE 4-4. REAR BRAKE WEAR TOO
in beyond the end face of the case, but IS NEAR
the service limit, carry out inspection more fre- 1. Handle 3. Stamped Line
quently. Check the retarder capacity carefully 2. Rod 4. Face Of The Cas
also.
J4-2 Brake Circuit Checkout and Adjustment J04009 11/

BRAKE BLEEDING
Start the engine and wait for the air gauge to enter th
green range, then bleed the air from the circuit a
follows.
Rear brake
1. Bleed the air at the slack adjuster end first. Depress FIGURE 4-5. SLACK ADJUSTER
the brake pedal, then loosen air bleed plugs (1 or
2, Figure 4-5) 3/4 turns. Tighten the plug again, 1. Air Bleed Plug 2. Air Bleed Plug
then release the pedal.
2. Continue this procedure until no more bubbles

come out from the air bleed plug hole, then bleed
the air from the wheel plug (1, Figure 4-6).
come out from the air bleed plug.
4. After bleeding the air, close the plug and fit the cap.
Front brake
FIGURE 4-6. BRAKE HOUSING BLEED PLUG
1. The oil tank is separately installed, so always check 1. Air Bleed Plug 2. Brake Housing
the oil level while bleeding the air to avoid running
out of oil.
2. Depress the brake pedal, then loosen air bleed

plug (1, Figure 4-7) 3/4 turn. Tighten the plug
again, then release the pedal.
come out from the air bleed plug.
FIGURE 4-7. FRONT BRAKE BLEED PLUGS
1. Air Bleed Plugs 2. Brake Lin

FRONT BRAKE IS INEFFECTIVE OR ONLY EFFECTIVE ON ONE SIDE.

REAR BRAKE IS INEFFECTIVE ORONLY EFFECTIVE ON ONE SIDE.

NOTES:

FRONT BRAKES
FRONT BRAKE CALIPER PAD
Removal
1. Refer to "Tire Removal ", Section "G" and remove

front wheel assembly.
2. Loosen Capscrew (2, Figure 5-1), and pull pin (1)
until the pads can be removed.
3. Remove pads (3, Figure 5-2).
NOTE: The brake pads have one end open and the
other end closed where the retaining pins hold the
pads in place. This allows the removal of the pads
without pulling all the pins.
4. Install a vinyl hose to bleeder screw (2) so that the
brake oil can be drained out. FIGURE 5-1. BRAKE PAD REPLACEMENT
1. Pin 2. Capscrew
5. Loosen the bleeder screw, and return piston (1) to
the bottom of the cylinder with a bar. Tighten
bleeder screw after oil is bled out and remove vinyl
hose.
Installation
1. Install brake pads.
2. Install pin (1, Figure 5-1) and tighten capscrew (2)
3. Bleed the air from the brake circuit. Refer to "Brake
Bleeding" this Section.
FIGURE 5-2. BRAKE PAD REPLACEMENT
1. Piston 3. Brake Pads

Brake Caliper Assembly 2. Bleeder Screw
Removal
1. Refer to "Tire Removal ", Section "G" and remove
front wheel assembly.
2. Disconnect the two brake lines (1, Figure 5-3).
3. Remove 13 mounting capscrews (3, Figure 5-4).
Use a suitable lifting device as support, remove
the remaining mounting capscrews, and remove
caliper assembly.
FIGURE 5-3. BRAKE CALIPER
1. Brake Lines 2. Caliper Assembly
J05010 11/98 Front Brakes J5-1

Installation
1. Using a suitable lifting device, install brake caliper
assembly. Using thread tightener Threebond
(TB1374), install and tighten mounting capscrews
(3, Figure 5-4) to 94.5 ± 10 kg.m (685 ± 72 ft.
lbs.) torque.
2. Connect the two brake lines (1, Figure 5-3).
3. Bleed the air from the brake circuit.
Refer to "Brake Bleeding" this Section.
Disassembly
1. Loosen capscrews (1, Figure 5-5) and (2), remove
pins (3), (4), and (5), the remove pads (6).
2. Remove plate (7), then remove plug (8), backup
ring (9), and seal (10).
3. Remove dust seal (11), then remove piston (12).
4. Disassemble the other pistons in the same way.
FRONT BRAKE INSPECTION

ITEM NEW LIMIT REMEDY
"A" - Disc 25 mm 22 mm Replace
(0.99 in) (0.87 in)
Disc 0.15 mm 0.5 mm Repair or
Runout (0.006 in) (0.02 in) Replace
"B" - Pad 19.5 mm 3.0 mm Replace
(0.77 in) (0.12 in)
NOTE: The brake disc can be machined as long as the
minimum thickness is not less than 22 mm (0.87 in) after
machining.
1. Brake Disc 4. Capscrew

2. Capscrew 5. Bleeder Valve
3. Capscrew 6. Brake Caliper
TIGHTENING TORQUES
FIGURE 5-4. BRAKE CALIPER REMOVAL 2. 94.5 ± 10 kg.m (685 ± 72 ft. lbs.) torque.
1. Mounting Plate 4. Brake Disc 3. 94.5 ± 10 kg.m (685 ± 72 ft. lbs.) torque.
2. Brake Caliper 5. Capscrew 4. 21.0 ± 1 kg.m (150 ± 7 ft. lbs.) torque.
3. Capscrew 6. Bleeder Valve
7. Capscrew 5. 2.6 ± 0.3 kg.m (20 ± 2 ft. lbs.) torque.
J5-2 Front Brakes J05010 11/98

Assembly
1. Install backup ring (1, Figure 5-6), ring (2), and dust
seal (3) in groove of housing (4) securely.
2. Fit the lip of the dust seal in the groove of the piston
(5) and install piston.
3. Fit seal (10, Figure 5-5), backup ring (9), and plug
(8), and install plate (7).
NOTE: 1 Move the pin in the axial direction while

tightening the bolts, and check that the bolt fits se-
curely in the groove of the pin.
NOTE: 2 Of thin pins (4) and (5), always install the short
pin (5) at the plate end.
4. Grease pins (3, 4, 5). Fit pads (6), and install pins
(3), (4), and (5), and tighten capscrews (2) and (1)
5. Assemble the other pistons in the same way.

FIGURE 5-5. BRAKE CALIPER REPAIR
6. Install caliper assembly. 1. Capscrews 9. Backup Ring
2. Capscrews 10. Seal
3. Pins 11. Dust Seal
4. Pins 12. Piston
5. Pins 13. Ring
6. Pads 14. Backup Ring
7. Plate 15. Housing
FIGURE 5-6. PISTON SEAL

1. Backup Ring 4. Housing
2. Ring 5. Piston
3. Dust Seal
J05010 11/98 Front Brakes J5-3

NOTES
J5-4 Front Brakes J05010 11/98

REAR WET DISC BRAKE ASSEMBLY
A Wet Disc Brake Assembly is mounted on both sides The complete brake disc pack is cooled by hydraulic
of the differential on the final drive housing and inboard oil. The cooling oil circuit is a low-pressure circuit which
from the wheel hub and planetary drive. This assembly is completely separate from the high-pressure piston
contains a splined housing, two damper discs, fourteen apply circuit. The cooling oil flows from the tank to the
separator plates, fifteen friction discs, a spacer, and a pump, to the brake assembly housing (from the outside
piston assembly. of the housing inward to the rotating hub for maximum
cooling), through a heat exchanger, through two 30
The housing is internally splined to retain the steel
micron (absolute) filters, and then to the hydraulic tank.
damper and separator discs. The separator discs are
alternately placed between the friction faced discs Dynamic retarding is also provided by the wet disc
which are splined to the rotating hub. The inboard side brakes. When the operator’s retarder lever is actuated,
of the assembly contains the piston assembly which is the front wheel brakes are not used; only the rear wet
activated by hydraulic pressure from either the service disc brakes are applied. The dynamic retarding is used
brake treadle valve or the retarder valve. As hydraulic to slow the truck during normal truck operation or to
pressure is applied, the piston moves and compresses control speed coming down a grade.
the rotating friction faced discs against the stationary
steel discs. The friction forces generated resist the
rotation of the wheels. As hydraulic pressure increases,
friction forces are increased and wheel rotation is WET DISC BRAKE ASSEMBLY
slowed until maximum force is reached and the wheel
is stopped. Removal
1. Remove rear wheels and tires, planetary drive, and
wheel hubs. Refer to Section "G", Drive Axle, Spin-
dles and Wheels.
2. Drain brake cooling oil tank. Be prepared to catch
268 l (71 gal.) of oil.
3. Remove retainer (1, Figure 6-2) and floating seal
(2, figure 6-3).
FIGURE 6-1. WET DISC BRAKE ASSEMBLY
1. Plate 3. Brake Disc FIGURE 6-2. RETAINER

2. Damper
1. Retainer 2. Housing
J06010 11/98 Rear Brakes J6-1

FIGURE 6-3. RETAINER
1. Retainer 2. Floating Seal
FIGURE 6-5. BRAKE ASSEMBLY
4. Remove hoses (1, Figure 6-4) and lines (2).
1. Brake Assembly 2. Lifting Device
6. Loosen the air bleed plug and remove piston (1,

Figure 6-6). Then remove Brake Disc Assembly
(2).
J060009
FIGURE 6-6.
FIGURE 6-4. BRAKE LINES
1. Piston 2. Brake Disc Assembly
1. Hydraulic Hoses 2. Hydraulic Lines
Installation
1. Install the brake disc assembly seal with the side

Brake assembly weighs approximately 610 kg with the groove facing the side taking the pres-
(1344 lbs.) Use adequate lifting devices. sure. Coat the capscrew threads with a thread
tightener Three Bond TB1374), then install the
Brake Disc Assembly (2). Tighten capscrews to
5. Remove brake assembly (1, Figure 6-5). 94.5 ± 10 kg.m (685 ± 72 ft. lbs.) torque.
2. Install the piston seal with the grooved side facing
the side taking the pressure and install piston (1,
Figure 6-6). Tighten the air bleed plug.
J6-2 Rear Brakes J06010 11/98

3. Coat the capscrew threads with thread tightener 3. Remove damper (2, Figure 6-8), disc (3), and plate
Three Bond (TB1374), then install the brake as- (4) from outer gear (1).
sembly (1, Figure 6-5). Tighten capscrews to 94.5
4. Remove mounting bolts, then remove hub (5) from
± 10 kg.m (685 ± 72 ft. lbs.) torque.
outer gear (1).
4. Install hoses (1, Figure 6-4) and lines (2).
5. Remove floating seal (6) from hub (5).
5. Install retainer (1, Figure 6-2) and floating seal (2,
figure 6-3).
6. Install rear wheels and tires, planetary drive, and
wheel hubs. Refer to Section "G", Drive Axle, Spin-
dles and Wheels.
7. Fill brake cooling oil tank.
WET DISC BRAKE

FIGURE 6-8. BRAKE DISCS AND HOUSING
Disassembly
1. Outer Gear 4. Plate
2. Damper 5. Hub
1. Remove tool (2, Figure 6-7) 3. Disc 6. Floating Seal
NOTE: Be careful not to damage the floating seal when

removing outer gear.
6. Remove floating seals (3, Figure 6-9) and (1) from
inner gear (2).
2. Using eyebolts, lift off outer gear (1) together with
disc and plate.
FIGURE 6-9. FLOATING SEALS

FIGURE 6-7. OUTER GEAR ASSEMBLY
1. Floating Seals 3. Floating Seals
1. Outer Gear 2. Tool (790-438-
1150) 2. Inner Gear

Inspection Assembly
Replace any worn or damaged parts. Clean all parts, and check for dirt or damage. Coat the
sliding surfaces of all parts with clean brake system oil
before installing.
When assembling the floating seals, use alcohol to
remove all the white powder from the O-ring surface
before assembling.
Tools for installation of rear wheel brake floating seal
• 791-585-1510 installer-large diameter
• 792-530-1700 push tool-large diameter
• 792-520-2110 installer-small diameter
• 792-530-1600 push tool-small diameter
1. Using tools (1, Figure 6-10) install floating seals (3,
Figure 6-9) and (1) to inner gear (2).
BRAKE DISC INSPECTION

1. Plate Dimension "A" =
2. Damper 123.9 mm(4.88 in.) Standard Height
3. Disc 115.0 mm(4.50 in.) Minimum Height
[Maximum Wear]
REAR BRAKE INSPECTION

ITEM STANDARD LIMIT REMEDY
Plate 2.4 mm (0.095 2.15 mm Replace
in) (0.085 in)
Disc 5.1 mm 4.6 mm Replace
(0.2 in) (0.18 in) FIGURE 6-10. FLOATING SEAL INSTALLATION
Damper 6.9 mm (0.27 in)5.1 mm Replace 1. Tool 3. Hub
(0.20 in) 2. Floating Seal
Max. Disc 0.45 mm (0.018 0.7 mm Replace
Warping in) (0.028 in) 2. Using tools (1), install floating seal (2) to hub (3).
Max. Plate 0.50 mm (0.020 0.7 mm Replace
Warping in) (0.028 in)
Assembled Dimension "A"
Thickness 123.9 mm 115.0 mm Replace
of Discs (4.88 in.) (4.5 in.)
and Plates
Backlash
between 0.21 - 0.64 mm 2.2 mm Replace
outer gear (0.008"- 0.025") (0.087 in.)
and plate
Backlash
between 0.21 - 0.64 mm 2.2 mm Replace
inner gear (0.008"- 0.025") (0.087 in.) FIGURE 6-11. SEAL INSTALLATION
and plate
NOTE: After installing the floating seals, measure di-
mension "a" (Figure 6-11) between the inner gear and
floating seal at four places around the circumference
and check that the measurement is within 1 mm (0.039
in).

3. Align match marks, and install hub (2, Figure 6-12)
to outer gear (1). Coat the capscrew threads with
thread tightener Three Bond (TB1374). Tighten
capscrews to 56 ± 6 kg.m (406 ± 43 ft. lbs.)
torque.
NOTE: Coat the sliding surfaces of the floating seals
thinly with engine oil. Assemble slowly and be careful
not to damage the floating seals.
4. Using eyebolts, assemble outer gear assembly (1,

Figure 6-13) to inner gear.
5. Align center of inner gear and outer gear (1, Figure
6-7), then using tool (2), secure inner gear and FIGURE 6-12. HUB INSTALLATION
outer gear.
1. Outer Hub 2. Hub
6. Between inner gear and outer gear assembly,
assemble one external splined damper (2, Figure
6-14) with cork face toward hub (away from disc).
Then install one internal splined disc (3), and one
external splined plate (1) alternately, until fifteen
discs and fourteen plates are used. Install second
damper with cork face away from disc.
7. Install brake assembly.
FIGURE 6-13. OUTER AND INNER GEARS

1. Outer Gear 2. Inner Gear
FIGURE 6-14. BRAKE DISC INSTALLATION

1. Plate 3. Brake Disc
2. Damper

NOTES

PARKING BRAKE
3. Loosen mounting capscrews (2), and sling so that
the caliper does not fall.
4. Move plate (4) when removing pads (3) so that the
For servicing any part of the parking brake, stop
pads do not fall.
the machine on level ground, and put blocks in
front of, and behind, the wheels. 5. After removing the rear pad, move the caliper to
Raise the dump body and lock with the safety pin. the front, and remove the front pad.
The parking brake is a dry disc brake mounted on the
Pad Installation
rear drive shaft at the differential input with two (2)
spring-applied, air-released calipers. Each caliper is 1. Install and align the grooves of the pad and the
individually applied/released through separate air caliper with the plates on both sides.
chamber actuators (spring cylinder assemblies).
2. Coat the threads of the plate mounting capscrews
(2, Figure 7-1) with thread tightener Three Bond
Inspection
(TB 1374). Tighten capscrews to 94.5 ± 10 kg.m
PARKING BRAKE INSPECTION (685 ± 72 ft.lbs.) torque.
ITEM NEW LIMIT REMEDY 3. Refer to "Park Brake Adjustment", this section and
Disc Face Runout 0.4 mm 0.8 mm Replace adjust the parking brake.
(0.016 in) (0.032 in)
Disc 25 mm 20 mm Replace PARKING BRAKE CALIPER
Thickness (0.99 in) (0.79 in)
Pad (Includes Plate 21.5 mm 11.5 mm Replace Caliper Removal
Thickness) (0.847 in) (0.45 in)
NOTE: The brake disc can be machined and reused

as long as it is not less than 20 mm (0.79 in) thick after
machining. Stop the machine on level ground, and put blocks
under wheels.
Pad Removal 1. Refer to "Parking Brake Spring Cylinder Assem-
bly", this section and remove parking brake spring
1. Turn the keyswitch ON, and release the parking
cylinder assembly.
brake lever.
2. Remove plate (1, Figure 7-2).
2. Turn capscrew (1, Figure 7-1) counterclockwise to
make clearance between the pad and disc larger. 3. Remove pads (2).
4. Remove caliper (3).
FIGURE 7-1. BRAKE PAD REPLACEMENT

FIGURE 7-2. BRAKE CALIPER ASSEMBLY
1. Adjusting Capscrew 3. Pad
2. Mounting Capscrew 4. Plate 1. Plate 3. Caliper
2. Brake Pads
J07008 11/98 Parking Brake J7-1

Caliper Installation Caliper Disassembly
1. Install caliper (3, Figure 7-2). 1. Remove snap ring (1, Figure 7-3), and pull out
adjuster (2).
2. Install pads (2).
2. Remove washers (3) and (4), and seal (5).
3. Coat the threads of the mounting capscrews with
thread tightener Three Bond (TB 1374). Tighten 3. Remove bolts, then remove cap (6) and gasket (7).
capscrews to 94.5 ± 10 kg.m (685 ± 72 ft.lbs.)
4. Remove piston shaft (8) and thrust bearing (9)
torque. Install plate (1).
from piston.
4. Refer to "Parking Brake Spring Cylinder Assem-
5. Remove piston (11) and piston seal (12) from
bly", this section and remove parking brake spring
caliper (10).
cylinder assembly.
FIGURE 7-3. PARKING BRAKE PISTON ASSEMBLY
1. Snap Ring 4. Washers 7. Gasket 10. Caliper

2. Adjuster 5. Seal 8. Shaft 11. Piston
3. Washers 6. Cap 9. Bearing 12. Piston Seal
J7-2 Parking Brake J07008 11/98

Caliper Assembly 3. With the parking brake applied, disconnect the air
hose (4) from the spring cylinder. Check that the
1. Apply grease (Mobilux EP 2 or equivalent) to
air pressure of the spring cylinder is released.
piston seal (12). Assemble piston seal (12) to
caliper (10), and insert piston (11). 4. Remove spring cylinder assembly (5).
2. Apply grease (Mobilux EP 2 or equivalent) to thrust
bearing (9). Screw piston shaft (8) into piston, and Installation
install thrust bearing (9).
1. Install spring cylinder assembly (5, Figure 7-4).
3. Fit gasket (7) and install cap (6). Tighten mounting nuts to 20 ± 2 kg.m (145 ± 15
ft. lbs.) torque.
4. Apply grease (Mobilux EP 2 or equivalent) to seal
(5). Fit the seal (5) securely in the groove and 2. Connect the air hose (4) and install pin (1).
install seal (5), and washers (3) and (4).
3. Refer to "Parking Brake Adjustment", this section
5. Assemble adjuster (2), and secure with snap ring and adjust parking brake.
(1).
Disassembly
PARKING BRAKE SPRING CYLINDER 1. Remove screw, then remove holder (1, Figure 7-5)
and filter (2).
Removal 2. Remove retainer (3) and nut, then remove boot (4).
3. Remove nuts (5) and (6), then remove shaft (7).
Stop the machine on level ground, and put blocks

under wheels.
Raise the dump body and lock with the safety pin.
1. Remove pin (1, Figure 7-4).
2. With the parking brake released, turn adjustment
capscrew (2) counterclockwise and check that
there is play in linkage (3).
FIGURE 7-5. PARKING BRAKE CYLINDER ASSY.

1. Holder 6. Nut 11. Support
FIGURE 7-4. SPRING CYLINDER ASSEMBLY 2. Filter 7. Shaft 12. Capscrew
1. Pin 4. Air Hose 3. Retainer 8. Nut 13. Spring
2. Adjusting Capscrew 5. Cylinder Assembly 4. Boot 9. Nut 14. Ring
3. Linkage 5. Nut 10. Piston 15. Ring
16. Case

4. Remove nut (8) from shaft (7). Assembly
Clean all parts, and check the inside of the cylinder for
dirt or damage.
Coat the sliding surfaces of all parts with grease and
The piston and support are under high pressure, be careful not to damage the rings when installing.
so be careful when operating the press.
1. Coat ring (17, Figure 7-5) with engine oil. Install
5. Using press, support piston (10) and support (11), rings (18) and (17) to case (16).
and remove bolts (12). Then loosen press slowly,
2. Coat ring (15) with engine oil. Install rings (15) and
and remove support (11) and spring (13).
(14) to piston (10), and set in case (16).
Also see Figure 7-6.
The piston and support are under high pressure,

so be careful when operating the press.
3. Apply adhesive to outer circumference of support
(11). Set spring (13) and support (11) in position,
and using press, slowly compress spring so that
support bolt hole matches cylinder bolt hole.
4. Align bolt hole, and install bolts (12). Tighten
capscrews to 1.4 ± 0.4 kg.m (10 ± 3 ft. lbs.)
torque.
5. Install nuts (9) and (8) to shaft (7).
6. Install shaft (7) to cylinder, then install nuts (5) and
FIGURE 7-6. SPRING ASSEMBLY
(6), and adjust dimension "a" (Figure 7-7) to 128
1. Piston 2. Support
mm (5.04 in.). Tighten nuts (1) to 7.25 ± 1.75 kg.m
(53 ± 13 ft. lbs.) torque.
6. Remove piston (10, Figure 7-5), then remove rings
(14) and (15) from piston. 7. Set boot (4, Figure 7-5) in position, and install nut
and retainer (3).
7. Remove rings (17) and (18) from case (16).
8. Set filter (2) in position, and install holder (1).
Dimension "a"
Rod Adjusted Length 128.0 mm (5.04 in.) Adjust
as
Dimension "b" 2.1 mm (0.08 in.)
Required
Axial Rod Play
Standard Size Standard
Clearance
Shaft Hole
Dimension "c"
Clearance between piston 38.04 mm 38.8 mm 0.76 mm
and insert center boss (1.50 in.) (1.53 in.) (0.03 in.) Replace
Parts
Dimension "d" as
Clearance between cylinder 158.65 mm 159 mm 0.35 mm Required.
and piston (6.25 in.) (6.26 in.) (0.014 in.)
Free Length Installed Load
260 mm 750 ± 50 kg
Item 2. Piston Spring
(10.24 in.) 1650 ± 110 lbs.
FIGURE 7-7. ROD ADJUSTMENT

PARKING BRAKE ADJUSTMENT
Testing
1. Stop the machine on level ground and apply the

parking brake.
2
2. Raise the air pressure to 8.3 kg/cm (118 psi).
3. Place the transmission shift lever in the D (F2)
position.
4. Raise the engine speed gradually and measure the
engine speed when the machine starts to move.
The minimum engine speed is 1,720 RPM.
NOTE: When the machine starts to move, release the
accelerator pedal, and depress the brake pedal and
return transmission shift lever to N at the same time.
FIGURE 7-9. PARKING BRAKE ADJUSTMENT
1. Pads 2. Brake Disc
Adjusting
1. Turn capscrew (1, Figure 7-8) clockwise and bring Standard clearance:
both pads (1, Figure 7-9) into contact with disc (2). Total for both clearances = 1.88 ± 0.08 mm.
2. Push in capscrew retainer (2, Figure 7-10) of slack (0.074 ± 0.003 in.) when pushed to one side;
adjuster (1) until the capscrew can turn, then turn or 0.8 mm each for both sides.
capscrew (3) clockwise. 4. After adjusting the pad clearance, actuating stroke
3. Turn capscrew (1, Figure 7-8) back from this "a" (Figure 7-10) of the rod should be measured
position counterclockwise 360° ± 15° and meas- and adjusted to approximately 50 mm (1.97 in).
ure clearance of caliper pad with feeler gauge (1, (Figure 7-12)
Figure 7-11). 5. After adjusting, return capscrew (2) to a position
where capscrew retainer (3) stops it from turning.
FIGURE 7-8. PARKING BRAKE ADJUSTMENT FIGURE 7-10. ARM ADJUSTMENT
1. Capscrew 3. Caliper 1. Slack Adjuster 3. Capscrew Retainer

2. Spring Housing 2. Capscrew a. 50 mm (1.97 in)

PARKING BRAKE DISC
The parking brake disc is mounted to the input flange
of the final drive differential assembly. If the parking
brake disc must be removed, the driveshaft between
the transmission output flange and the input flange of
the final drive differential must first be removed.
Driveshaft Removal
1. Remove guard (1, Figure 7-13) and cover (2).

FIGURE 7-11. ADJUSTMENT CLEARANCE ity to handle 1500 kg (3307 lbs).
1. Feeler Gauge 2. Adjustment Plug
2. Install lifting sling securely around driveshaft and
remove capscrews (4) retaining driveshaft at both
ends.
3. Remove driveshaft assembly (3).
Parking Brake Disc Removal

1. Install lifting sling securely around parking brake
disc (4, Figure 7-14).
2. Remove capscrews (1) holding park brake disc.
3. Remove brake disc and refer to "PARKING BRAKE
INSPECTION" chart to determine serviceability of
parking brake disc.
FIGURE 7-12. ADJUSTING CLEARANCE

1. Adjustment Plug 2. Measuring Rod
FIGURE 7-13. DRIVESHAFT ATTACHMENT

FIGURE 7-14. PARKING BRAKE INSTALLATION
1. Guard 3. Driveshaft Assembly
1. Capscrew 3. Capscrew (Spring
2. Cover 4. Driveshaft Capscrew s (Disc Mounting) Cylinder Mounting)
2. Capscrew 4. Brake Disc

BRAKE RELEASE
Releasing Parking Brake And Emergency Brake
After Being Actuated In An Emergency
If the pressure inside the air tank drops abnormally due
to some problem, such as leakage of air from the air
circuit, the parking brake and emergency brake are
automatically actuated.
RELEASE OF PARKING BRAKE

Each parking brake caliper is individually applied and
released through separate air chamber actuators
(spring cylinder assemblies). If the parking brake can
not be released after its emergency application – even
if the parking brake valve lever is put in RELEASE
position – take the following actions to release the
FIGURE 7-15. PARK BRAKE INSPECTION parking brake:
1. Brake Pads 3. Capscrew
2. Brake Caliper 4. Brake Disc 1. Block disabled truck to prevent movement and
confirm safety in the surrounding area.
PARKING BRAKE INSPECTION 2. At parking brake relay valve, remove both air hoses
ITEM NEW LIMIT REMEDY (4, Figure 7-16) connected to the air chambers of
"a" - Pad (Includes 21.5 mm 11.5 mm Replace
the parking brake spring cylinder assemblies (5).
Plate Thickness) (0.847 in) (0.45 in) 3. Connect these hoses together using a “tee” fitting
"b" - Disc 25 mm 20 mm Replace with compatible thread ends.
Thickness (0.99 in) (0.79 in)
4. Connect third connector of “tee” to a hose from
Disc Face Runout 0.4 mm 0.8 mm Replace
(0.016 in) (0.032 in) an air supply of sufficient capacity to release cali-
pers. Apply air and release brake.
NOTE: The brake disc can be machined and reused as
long as it is not less than 20 mm (0.79 in) thick after 5. With parking brake released, turn adjustment bolt
machining. (2) counterclockwise, and check for “play” in link-
age (3). Remove pin (1). Repeat for other caliper.
Parking Brake Disc Installation Disconnect air supply.
1. Install lifting sling securely around parking brake

disc (4, Figure 7-14) and move disc into position.
2. Install capscrews (1) holding park brake disc.
Tighten capscrews to 56 ± 6 kg.m (400 ± 40
ft.lbs.) torque.
Driveshaft Installation

ity to handle 1500 kg (3307 lbs).
1. Install lifting sling securely around driveshaft and
install cover (2, Figure 7-13) and driveshaft as-
sembly (3). Install capscrews (4) and tighten to 18 FIGURE 7-16. SPRING CYLINDER ASSEMBLY
± 2 kg.m (130 ± 13 ft.lbs.) torque. 1. Pin 4. Air Hose
2. Adjusting Capscrew 5. Cylinder Assembly
2. Install guard (1).
3. Linkage

6. With parking brake disconnected, remove block- RELEASE OF EMERGENCY BRAKE
ing and immediately move the truck to a safe
place. Refer to INSTRUCTIONS FOR TOWING
THE MACHINE.
If the air system is not operating, the service brakes

will not apply; this is very dangerous.
Be sure to tow the truck at low speed, keeping the
engine running (if possible) and always be ready
to steer.
Refer to Parking Brake Inspection and Adjustment, for

instructions for reconnecting and adjusting park brake. FIGURE 7-17. RELEASING EMERGENCY BRAKE
1. Air Quick Disconnect 2. Drain Valve

Pull Rings
When the emergency brake has been applied, do not

continue to drive the machine. This will cause seizure
of the brake discs and linings.
If the emergency brake can not be released after its
emergency application – even if the emergency brake
valve lever is put in RELEASE position – release the
emergency brake in the following manner:
Before releasing the air pressure from the emergency
brake reservoir, confirm safety in the surrounding area
and put chocks against the tires.
1. After making preparations to tow the machine, pull
rings (2, Figure 7-17) on the 4 drain valves on the
front air tanks to release the air pressure.
2. After exhausting all air pressure, release rings (2).
3. Drain the rear air tank by pulling and holding the
ring on the air drain valve mounted on the frame
in front of the right rear suspension. Keep drain
valve open until all air is exhausted from tank. This
will allow the emergency brake to release.

SECTION K
AIR SYSTEM
INDEX
AIR SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K2-1

AIR SYSTEM OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K2-1
COMPONENT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K2-1
Main Air Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K2-1
Safety Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K2-1
Air Governor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K2-1
Air Dryer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K2-2
Air Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K2-4
AIR SYSTEM COMPONENT REPAIR

Air Compressor Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K3-1
Air Governor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K3-1
RETARDER VALVE
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K5-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K5-1
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K5-3
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K5-3
K01014 Index K1-1

NOTES
K1-2 Index K01014

AIR SYSTEM
AIR SYSTEM OPERATION
The engine driven air compressor pulls filtered inlet air
from the air cleaners. The compressed air is ported
through an air filter, air dryer, a one way check valve,
then into the main air tank.
From the tank, air is passed to an air governor. The air
governor controls the pressure in the system and
opens the purge valve at the air dryer. A safety valve
on the air tank prevents excessive pressurization. The
air is then delivered to the various circuits of the air
system. Refer to Section “R” for Air Schematic.
COMPONENT DESCRIPTION
Main Air Tank

The main air tank stores 15 cu. ft. of compressed air
and supplies air pressure to the various air circuits as
required. The pressure in the air tank is controlled by
the air governor (Figure 2-2) which maintains air pres-
sure of 7.0-8.3 kg/cm2 (100-120 psi). The air tank is
equipped with a safety valve which prevents the maxi-
mum air pressure in the tank from exceeding 9.5 ±0.4
kg/cm2 ( 135 ±6 psi). The tank is also equipped with a
moisture ejection valve (4) to eject excess moisture
that condenses inside the air tank.
Safety Valve
The safety valve (Figure 2-1) protects the air system FIGURE 2-2. AIR GOVERNOR
against excessive air pressure above 9.5 ±0.4 kg/cm2
( 135 ±6 psi). It is installed on the main air tank.
If main pressure below the ball valve rises to a point Air Governor
above the setting of the safety valve, the pressure Air pressure from the air tank enters the inlet port of
developed will overcome spring force holding the ball the governor (Figure 2-2), passes through a filter and
on its seat and the ball will lift. This action permits air acts on the bottom of the piston and valve.
to pass up into the spring cage and exhaust to atmos-
phere through the exhaust port. As soon as excess When air pressure reaches 8.3 ±0.3 kg/cm2 (120 ±4
pressure in the air tank has been reduced to safety psi ), the piston moves upward unseating the valve. Air
valve setting, the regulating spring forces the ball back pressure flows through the drilled passage in the pis-
on its seat, stopping the exhaust of air. Normally the ton and out the unloader port to the compressor intake
safety valve remains closed. It functions only when air valve.
pressure rises above 9.5 ±0.4 kg/cm2 ( 135 ±6 psi). As the pressure drops to 7.0 ±0.3 kg/cm2 (100 ±4 psi),
force exerted by air pressure on the bottom of the
piston will be reduced so that the spring force will move
the piston down. The inlet valve closes and the exhaust
valve opens allowing pressure in the unloader line to
vent through the exhaust ports. With pressure re-
leased in the unloader line, the compressor will pres-
FIGURE 2-1. SAFETY VALVE surize the air tank.
K02014 11/98 Air System K2-1

FIGURE 2-3. AIR DRYER OPERATION
1. Governor 4. To Air System 7. Wet Reservoir 10. Hose
2. Check Valve 5. Dry Reservoir 8. Exhaust 11. Connector
3. Hose 6. Safety Valve 9. Hose 12. Compressor
13. Expansion Tank
AIR DRYER Function
The Air Dryer removes moisture, oil, carbon and dirt The compressed and heated air from the compressor
from the compressed air sent from the air compressor enters the bottom of the after-cooler and undergoes
and sends the clean, dry air back to the air reservoir. adiabatic expansion. It is cooled and the moisture in
The moisture removed from the air is automatically the air forms drops of water and collects at the end cap
discharged into the atmosphere when the unloader (27, Figure 2-4). The body (26) of the Air Dryer is made
valve in the air compressor moves. of aluminum. There are numerous fins fitted on the
outer cylinder and these are cooled when the machine
is moving. This prevents overheating by the air sent
from the compressor.
FIGURE 2-4 AIR DRYER

1. Mounting Angle 17. Spindle 33. Piston 48. O-Ring
2. Mounting Angle 18. Spring 34. Cup 49. Unloader Valve Seat
3. Nut 19. Bolt 35. Washer, leveling 50. O-Ring
4. Bolt 20. Filter Cup 36. Spindle 51. Seal Ring, Rectangular
5. Mounting Strap 21. Filter 37. Spring 52. Unloader Valve Stop
6. Heater/Thermo 22. Strainer 38. Washer, Anti Extr 53. Check Valve Seat
7. Heater Cover 23. "V" Spring 39. Ball 54. Check Valve
8. Set Screw 24. Packing Ring 40. Washer, Compression 55. Washer
9. Bolt 25. Deflector 41. Retaining Screw 56. Turbo Tube Assembly
10. Spring 26. Body 42. Nut 57. Turbo Check Valve
11. O-Ring 27. Bottom Cap 43. Bullet Receptacle 58. Turbo Tube Fitting
12. Safety Valve 28. Bolt 44. Label, I.D./Serial Number 59. Washer
13. Top Cap 29. Seal Retainer 45. Label, Pressure Warning 60. Deflector Plate
14. Gasket 30. O-Ring 46. O-Ring 61. Deflector Extent
15. Nut Adapter 31. Sleeve 47. Comp Unloader Valve 62. Deflector Rod
16. Ball 32. O-Ring
K2-2 Air System K02014 11/98

FIGURE 2-4. AIR DRYER
K02014 11/98 Air System K2-3

Cleaning the exhaust port HORN SOLENOID
Whenever the exhaust port is clogged with dust, re-
move bolt (9, Figure 2-4) and take out the inner parts. FUNCTION
Also remove unloader valve parts 47, 48, 49, 50, 51, When the horn button on the steering wheel is pressed,
52, 53, and 54. Clean the removed parts thoroughly. the electric circuit is closed and electricity flows to the
After moisture has been removed from the air, the air coil to form an electromagnet that raises the piston.
passes through filter (21) and strainer (22), where oil, Compressed air then flows to sound the horn.
carbon and dirt are removed. This clean, dry air passes
through the check valve at the top of the dryer and is
sent to the air reservoir. If the pressure in the air
reservoir goes above the specified pressure, the gov-
ernor works to unload the air compressor. This un-
loader piping is connected to the unload port of the
after-cooler.
Every time the air compressor is unloaded, the air in
the air dryer is released into the atmosphere, so the
water and oil collected at the end cap (27) is dis-
charged at the same time.
Maintenance
Disassemble and wash the Deflector (25) and the filter
(21) every six months or every 3,000 hours. To disas-
semble the Air Dryer, loosen the bolts (19) first, take FIGURE 2-5. HORN SOLENOID
off the top cap (13), and take out the filter cup (20).
1. Coil Assembly 4. Filter
Then, loosen the nuts (42) and disassemble the de-
2. Core 5. Terminal
flector parts (25, 60, 61 and 62).
3. Plunger
Three service kits are available:
Filter Service Kit RK1486 includes items 14, 21, and
24.
Filter Replacement Kit RK0108 includes items 1, 2, 5,
6, 14, 20, 21, 22, 23, and 24.
Check valve kit RK1869 includes items 10, 16, and 17.
K2-4 Air System K02014 11/98

AIR SYSTEM COMPONENT REPAIR
AIR COMPRESSOR SERVICE
The air compressor is a component of the engine
assembly. Refer to the engine manufacture’s service
manual for removal and repair instructions.
AIR GOVERN0R
Removal
1. Open the drain valve of the air tank and release the
air pressure.
2. Remove lines (1, Figure 3-1).
3. Remove mounting capscrews and air governor
assembly (2).
Installation
Carry out installation the reverse order to removal.
Disassembly
2. Remove snap ring (11), then remove adjustment
screw and spring assembly (10).
3. Pull out piston assembly (3), and remove stem (9)
and spring (8).
FIGURE 3-2. AIR GOVERNOR PARTS
1. Body 8. Exhaust Spring

2. Filter 9. Exhaust Stem
3. Piston 10. Adjuster Assembly
FIGURE 3-1. AIR GOVERNOR 4. Grommet 11. Snap Ring
5. Pressure Valve 12. Cover
6. Spring 13. Washer
1. Air Lines 2. Air Governor 7. O-Ring
K03007 Air System Component Repair K3-1

Assembly
Clean all parts, and check for dirt or damage, then coat
all parts with grease before installing.
1. Fit O-ring and install spring (8) and stem (9) to
piston (3).
2. Fit O-ring and install piston assembly (3) to body
(1).
3. Fit adjustment screw and spring assembly (10) to
body (1), then install snap ring (11).
NOTE: After installing to the machine, check the air
pressure.
FIGURE 3-3. AIR GOVERNOR CROSS SECTION
K3-2 Air System Component Repair K03007

RETARDER VALVE
RETARDER FUNCTION
The rear oil-cooled, multiple-disc retarder brakes are
automatically activated when the engine speed ex-
ceeds the rated revolutions of the shift position. How-
ever, these brakes can be applied manually by moving
the retarder control lever which is mounted on the
steering column. Be certain that the air hoses are connected se-
curely before proceeding. Failure to do so could
result in bodily harm and/or damage to the interior
of the cab.
Removal
4. Start the truck and allow the air pressure to rise

to full pressure.
5. Attach a hanging scale to the handle assembly
NOTE: Relieve air pressure from the system be- lever (21).
fore working with or on the retarder valve/lever
5. With supply air pressure at 740 kPa (107.32 psi),
assembly. Failure to do so could result in bodily
to maintain minimum lever force of 2.9~4.9 N
harm and/or damage to the interior of the cab.
(0.3~0.5 kgf) to move lever to 190 mm (0.75 in.)
1. Shut the engine down and turn off the key switch. from center when releasing air pressure, turn
case (17, Figure 5-1) to tighten or loosen tension
2. After air pressure has been relieved from the
on spring (18) and secure with nut (16). Tighten
system, disconnect the three air hoses from the
nut to 9.8~14.7 N.m (7.23~10.85 ft. lbs.) torque.
ports in the bottom of the retarder valve body
(Figure 5-1). Mark the hoses to indicate their
appropriate ports for future reference at installa-
NOTE: DO NOT turn the case inward more than four
tion.
turns after initial contact between case (17), spring
3. Remove the two bolts (3, Figure 5-2) and lock- (18), and plunger (19) is made.
washers (4) from the clamp (5). Separate the
clamp from the body and remove the spacer (2).
Remove the retarder valve/lever assembly from
the steering column.
Installation
1. Hold the clamping area of the retarder valve body
(1, Figure 5-2) against the steering column so that
the lever extends to the right of the column.
2. Install clamp (5) opposite the valve body around
the steering column and install bolts (3) and lock-
washers (4).
3. Connect the three air hoses to the appropriate
ports in the bottom of the retarder valve body
(Figure 5-1).
NOTE: If the lever replacement kit has been installed, FIGURE 5-1. PORTS
it may be necessary to adjust the lever friction after
installation. If adjustment is required, proceed with the 1. Supply 3. Delivery
following steps. 2. Exhaust
K05005 Retarder Valve K5-1

FIGURE 5-2. RETARDER VALVE AND LEVER ASSEMBLY
1. Valve Body 9. Valve 17. Case 25. Nut

2. Spacer 10. Bolt 18. Spring 26. O-Ring
3. Bolt 11. Lockwasher 19. Plunger 27. Lockwasher
4. Lockwasher 12. Gasket 20. Screw 28. Ring
5. Clamp 13. Spring 21. Handle Assembly 29. Cover
6. Valve Stem 14. O-Ring 22. Plate 30. Cam Follower
7. Spring 15. Piston 23. Bolt 31. Cam
8. Guide 16. Nut 24. Washer 32. Spring
K5-2 Retarder Valve K05005

Disassembly 4. Apply gasket (12) to valve body (1) and seat cover
(29) on gasket.
1. Remove bolts (10, Figure 5-2) and lockwashers
(11) from valve body (1). 5. Install cover (29) over internal parts onto valve
body (1). Install bolts (10) and lockwashers (11).
2. Remove bolt (23), nut (25), and washer (24) from
Tighten bolts to standard torque.
plate (22).
6. Install o-ring (26) over cover (29).
3. Separate handle assembly (21) from cover (29).
Remove lockwasher (27) and unscrew ring (28) 7. Install exhaust valve (9), guide(8), spring (7) and
from cover (29). Lift cover (29) from valve body valve stem (6) into exhaust port (2, Figure 5-1).
(1). Separate internal parts.
8. Apply Locktite to set screw (20) and install in
4. Remove setscrew (20) from handle assembly handle assembly. Tighten to 0.98~1.5 N.m
(21). Loosen nut (16) and remove case (17), (0.72~1.09 ft. lbs.) torque.
spring (18), and plunger (19) from handle assem-
9. Install plunger (19, Figure 5-2), spring (18), case
bly (21).
(17) and nut (16) into handle assembly (21).
NOTE: Spring (18) tension should be adjusted as

Assembly
outlined in installation steps 4, 5, and 6 on page K5-1
1. Install o-ring (14) onto piston (15). Seat spring (13) after retarder valve/lever assembly is installed in truck.
and piston into valve body (1),
2. Install spring (32), cam (31) and cam follower (30)
into valve body (1) with spring seated on piston 10. Install handle assembly (21) onto cover (29).
(15).
11. Install plate (22) over cover (29) and secure with
3. Place ring (28) over cam follower (30) and install bolt (23), washer (24) and nut (25). Tighten nut
lockwasher (27) in top of ring. (25) to 0.98~1.5 N.m (0.72~1.09 ft. lbs.).
K05005 Retarder Valve K5-3

NOTES
K5-4 Retarder Valve K05005

SECTION L
HYDRAULIC SYSTEM
INDEX
HYDRAULIC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L2-1

HYDRAULIC SYSTEM OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L2-1
COMPONENT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L2-1
HYDRAULIC SYSTEM COMPONENT REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . L3-1

HYDRAULIC PUMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-1
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-1
HYDRAULIC TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-2
Filling Instructions (Hoist Oil Supply) . . . . . . . . . . . . . . . . . . . . . . . . . . L3-2
Filling Instructions (Rear Brake Cooling Oil Supply) . . . . . . . . . . . . . . . . . . L3-2
HYDRAULIC FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-3
Filter Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-3
HYDRAULIC TANK BREATHER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-3
Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-3
HIGH PRESSURE HYDRAULIC FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . L3-4
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-4
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-4
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-5
STEERING CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-1

STEERING CIRCUIT OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-1
DEMAND VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-2
STEERING CONTROL VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-2
CROSSOVER RELIEF VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-3
Operation Of Demand And Steering Control Valve . . . . . . . . . . . . . . . . . . . L4-4
EMERGENCY STEERING SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-12
FLOW SWITCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-13
RELAY TIMER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-13
Emergency Steering System Electrical Schematic . . . . . . . . . . . . . . . . . . . L4-14
STEERING VALVE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-1
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-2
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-7
L01028 Index L1-1

STEERING CIRCUIT COMPONENT REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . L6-1
EMERGENCY STEERING MOTOR PUMP ASSEMBLY . . . . . . . . . . . . . . . . . . . . L6-1
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-1
STEERING CYLINDER ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-2
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-2
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-2
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-3
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-5
DEMAND VALVE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-7
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-7
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-7
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-8
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-8
RELIEF VALVE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-9
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-9
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-9
HOIST CIRCUI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L7-1

CIRCUIT OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L7-1
COMPONENT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L7-1
HOIST CIRCUIT COMPONENT REPAI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-1

HOIST VALVE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-1
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-1
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-2
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-2
HOIST CYLINDER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-4
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-4
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-5
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-6
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-6
HYDRAULIC SYSTEM CHECKOUT . . . . . . . . . . . . . . . . . . . . . . . . . . .

L10-1 . . . .
Dump Body Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
L10-1 . . . .
Adjusting Hoist Lever Linkage . . . . . . . . . . . . . . . . . . . . . . . . . . . .
L10-2 . . . .
Adjusting Hoist Limiter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
L10-3 . . . .
Testing and Adjusting Hydraulic Pressure in Steering and Hoist Circuit . . . . . . . . . L10-4
Diagnostic Chart: Hoist System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-7
Diagnostic Chart: Steering System . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-10
L1-2 Index L01028

HYDRAULIC SYSTEM
HYDRAULIC SYSTEM OPERATION
NOTE: Refer to hydraulic system schematic in Section Oil being returned to the tank from the steering and
“R”. hoist circuits flows through a filter element mounted on
top of the tank. Should the filter become restricted, a
The steering and hoist circuits use a common hydraulic bypass valve will open allowing the oil to bypass the
tank located on the left side of the truck. The tank is filter element. The differential pressure at which the
divided into two sections; one for the steering and hoist bypass will open is 1.27 kg/cm2 (18 psi).
and another for the wet disc brake cooling oil. The front
section is for the steering and hoist and the rear section Oil for the wet disc brake cooling circuit flows from the
is for the wet disc brake cooling. Oil used for steering pump through tubing and hoses to the wet disc brake
and hoist flows from the bottom of the tank to the inlet housings. Return oil flows from the brake housings to
housing of the pump mounted on the left upper PTO the brake oil cooler and then back to the rear section
of the transmission. Some pressurization occurs dur- of the hydraulic tank and passes through two filters
ing truck operation as the hoist cylinders are retracted mounted on top of the hydraulic tank before returning
and oil returns to the tank. This pressure is relieved by to the tank.
a breather valve mounted on top of the tank. In the rear The three return filters (one hydraulic, two brake cool-
section of the tank, oil flows from the bottom of the tank ing) on the tank have bypass valves that will allow oil
to the inlet housing of the pump mounted on the right to bypass the filters if one becomes restricted. The
top PTO of the transmission. differential pressure which causes the bypass valve to
The demand valve is mounted on the front side of the open is 1.27 kg/cm2 (18 psi).
hydraulic tank mounting bracket. This valve directs the A brake control valve (BCV) is mounted in the circuit
oil flow from the steering and hoist pump. The oil flow from the pump to the wet disc brake housing. When
is first directed to the steering circuit and after the the disc brakes are not being used, the Brake Control
demand is met, the spool shifts directing oil flow to the Valve bypasses some of the cooling oil back to the
hoist circuit. Anytime steering is being used, the spool tank. This reduces power loss caused by excessive oil
is shifted to meet the steering demand by load sense flowing through the brake housing. Also built into this
pressure from the steering control valve. The demand valve is a pilot relief valve which will actuate at 9
valve has a 210 kg/cm2 (2986psi) relief valve mounted kg/cm2 (128 psi). When actuated, the pilot relief valve
in it to regulate the steering pressure. will cause the main relief valves to open allowing the
Return oil from the steering cylinder flows to the top of excess oil to return to the tank.
the tank and through a filter before returning to the
tank. In the hoist valve return line is an orifice plate COMPONENT DESCRIPTION
which causes some of the oil to flow through a steering
oil cooler mounted in front of the radiator. After going PUMP
through the cooler, oil returns to the front section of the
hydraulic tank. The truck is equipped with two double gear type
pumps. The steering and hoist circuit pump has two
The hoist valve is located on the rear hydraulic tank inlets and two outlets. The total output from the pump
mounting bracket, between the tank and the left frame at 2000 RPM is 668 l/min. (177 GPM) at a pressure of
rail. Oil from the demand valve flows to the hoist valve 210 kg/cm2 (2986 psi).
inlet and back to the tank through the oil filter mounted
on top of the tank if the operator is not using the hoist The wet disc brake cooling pump is also a double gear
circuit. The hoist valve is controlled by the operator type pump that has two inlets and two outlets. The total
through cables and linkages. The operator can direct output from the pump at 2000 RPM is 1051 l/min. (278
the flow of oil in the hoist valve to raise or lower the GPM) at 30 kg/cm2 (426 psi).
dump body. An adjustable internal relief valve protects
the hoist circuit from pressures in excess of 210 kg/cm2
(2986 psi).
L02023 11/98 Hydraulic System L2-1

TANK
The hydraulic tank is mounted to the left frame rail. It Oil returning to the hydraulic tank from the steering and
is separated into two sections. One for steering and hoist circuit passes through a 30 micron filter assem-
hoist the other for the wet disc brake cooling oil. The bly. The oil from the brake cooling circuit passes
service capacity for the steering and hoist section is through two 30 micron filter assemblies. These filters
162 liters (42.8 gal.). and for the rear brake cooling are accessible by removal of a cover plate for each
section is 268 liters (70.8 gal.). filter.
The oil level should be checked periodically with the
body down, engine stopped and parked on level
NOTE: The oil recommended for use in both sections
ground.
of the hydraulic tank (steering/hoist and brake cooling)
is A.P.I. classification CD SAE-10W engine oil.
Refer to “Lubrication and Service” Section “P” for
additional information regarding hydraulic system
service intervals, capacities and oil specifications.
FIGURE 2-2. HOIST VALVE LINKAGE
1. Shaft 2. Lever
FIGURE 2-1. HOIST RELIEF VALVE
1. Relief Valve 2. Housing
L2-2 Hydraulic System L02023 11/98

FIGURE 2-3. HOIST VALVE
1. Drain to Tank 4. To Hoist Cylinder

2. Return to Tank 5. To Hoist Cylinder
3. From Demand Valve 6. Lead Off Line
L02023 11/98 Hydraulic System L2-3

FIGURE 2-4. HYDRAULIC COMPONENT LOCATION
1. Power Down Line 8. Oil Cooler Inlet Hose 15. Steering and Hoist Filter
2. Power Up Line 9. LS Steering Line 16. Brake Cooling Filters
3. Suction Line 10. Steering Return Line 17. Oil Tank
4. Brake Cooling Pump 11. Steering Pressure Line 18. Hoist Valve Inlet Line
5. Steering and Hoist Pump 12. Demand Valve Inlet Lines 19. Orifice Plate
6. Flow Switch 13. Demand Valve 20. Hoist Valve Bleed Line
7. Oil Cooler Return Hose 14. Return Line To Tank 21. Hoist Valve
22. High Pressure Filters
L2-4 Hydraulic System L02023 11/98

HYDRAULIC SYSTEM COMPONENT REPAIR
HYDRAULIC PUMP
Raise the dump body and lock with the safety pin
prior to working on components.
Removal
1. Remove tubes (1 & 2, Figure 3-2). Cap tubes and
pump ports.
2. Remove hoses (1 & 2, Figure 3-3). Cap hoses and
pump ports. FIGURE 3-2. HYDRAULIC PUMP PIPING
3. Remove hydraulic pump assembly (3, Figure 3-2). 1. Pump Inlet Tube 3. Hydraulic Pump
2. Pump Inlet Tube
FIGURE 3-1. HYDRAULIC PUMP ASSEMBLY

1. Drive Gear 3. Gear Case 5. Front Cover 7. Gear Case 9. Driven Gear
2. Front Cover 4. Rear Cover 6. Drive Gear 8. Rear Cover 10. Driven Gear
L03025 Hydraulic System Component Repair L3-1

Installation
1. Install hydraulic pump assembly. Tighten cap-
screws to standard torque.
2. Remove caps and install hoses (1 & 2, Figure 3-3).
3. Remove caps and install tubes (1 & 2, Figure 3-2).
4. Refill hydraulic system as required. Refer to “Filling
Instructions”.
5. Bleed all air from inlet and outlet lines before
starting engine.
HYDRAULIC TANK
Filling instructions (hoist oil supply)

1. Lower the dump body and shut down the engine. FIGURE 3-3. HYDRAULIC PUMP
1. Outlet Hose 3. Hydraulic Pump
2. Outlet Hose
Release hydraulic tank filler caps slowly to remove

any internal pressure.
2. Turn the oil filler cap (3, Figure 3-4) slowly coun-
terclockwise to release internal tank pressure.
3. Fill tank with recommended oil (refer to Section P,
“Lubrication and Service”) until oil is visible in the
sight glass (4).
• Hydraulic tank refill capacity: 162 Liters
(42.8 gal.)
4. Replace fill cap.
5. If hydraulic components have been removed and
lines drained, start the engine and raise the dump
body 2-3 times to circulate oil.
6. Shut down the engine and repeat steps 2. through
4. if necessary.
Filling instructions (rear brake cooling oil supply)

1. Lower the dump body and shut down the engine.
2. Turn the oil filler cap (8, Figure 3-4) slowly coun-
FIGURE 3-4. HYDRAULIC TANK
3. Fill tank with recommended oil (refer to Section P,
“Lubrication and Service”) until oil is visible in the 1. Filter Covers 6. Brake Oil Drain
sight glass (7). 2. Bolts 7. Brake Cooling Oil
3. Hydraulic Oil Filler Sight Glass
• Rear Brake Oil tank refill capacity: 268 Liters Cap 8. Brake Cooling Oil
(70.8 gal.) 4. Hydraulic Oil Level Filler Cap.
4. Replace fill cap. Sight Glass 9. Breather
L3-2 Hydraulic System Component Repair L03025

HYDRAULIC TANK FILTERS
Filter Replacement
Release hydraulic tank filler cap slowly to remove

2. Turn the oil filler caps (3 & 8, Figure 3-4) slowly

counterclockwise to release internal tank pres-
sure.
3. Remove bolts (2) on filter covers (1).
4. Remove the elements (2, Figure 3-5) from housing.
5. Thoroughly clean filter housings, covers (4) and FIGURE 3-5. HYDRAULIC TANK FILTERS
bypass valve (3) components. 1. Hydraulic Tank 3. Bypass Valve
2. Filter Element 4. Cover
6. Install new elements. Install bypass valves and
covers. Tighten bolts (2, Figure 3-4) to standard
torque.
7. Check oil level; oil must be visible in sight glass.
HYDRAULIC TANK BREATHER

Cleaning
1. Shut down the engine and open hydraulic tank
filler caps slowly to relieve any internal pressure.
2. Clean dirt accumulation from area of breather (9,
Figure 3-4).
3. Remove the breather from the tank.
4. Remove snap ring (1, Figure 3-6), cover (2) and
filter element (3).
NOTE: If breather is equipped with a nut, remove nut
instead of snap ring to remove element.
5. Clean breather element in solvent and blow dry.
Clean remaining parts in solvent and dry thor-
oughly. FIGURE 3-6. HYDRAULIC TANK BREATHER
6. Install element, cover and snap ring. 1. Snap Ring 3. Element
2. Cover
NOTE: If equipped with a nut instead of a snap ring,
tighten nut, but do not overtighten as the stud will twist
off easily.
7. Install breather element on hydraulic tank.

HIGH PRESSURE HYDRAULIC FILTERS
Filter Assembly Removal
Clean dirt accumulation from the high pressure
hydraulic filters and tube connections in front of
the hydraulic tank.

sufficient force to enter a person’s body by pene-
sibly death if proper medical treatment by a
immediately.

counterclockwise to release internal tank pres-
sure.
FIGURE 3-7. HIGH PRESSURE FILTERS & PIPING
3. Place a receptacle under the filters to receive 1. Capscrew 8. Capscrew
hydraulic oil which will drain from filters when 2. Washer 9. Washer
disconnected. 3. O-Ring 10. Split Flange
4. Remove capscrews (1, 4, & 8, Figure 3-7), washers 4. Capscrew 11. Bracket (on Hyd. Tank)
(2, 5, & 9), and split flages (10) securing filters (7). 5. Washer 12. Washer
Move hydraulic tubes away from filter housings. 6. U-Bolt 13. Nut
7. Filter Assembly
5. Remove nuts (13) and washers (12) holding U-
bolts (6) to bracket (11). Remove filter assemblies
(7). Discard O-rings (3).
Plug or cover all open hydraulic connections to
prevent entry of contaminants and move filter
assemblies to a clean service area.
Filter Assembly Installation

1. Remove plugs and/or covers from connections. 4. Carefully align all components and connections to
Install new O-rings (3, Figure 3-7) in all locations. prevent any binding or kinking and then begin
Install filter assemblies (7) to outlets and install tightening all capscrews and nuts sequencially to
capscrews (1 & 4), washers (2 & 5). Do not tighten final standard torque.
capscrews to final torque at this time.
2. Move hydraulic tubes to filter housings inlets and
reconnect with capscrews (8), washers (9), and
split flages (10). Do not tighten capscrews to final Tighten all connections before starting engine and
torque at this time. applying hydraulic pressure.
3. Install U-bolts (6) holding filter assemblies (7) to 5. Start engine and check for leaks before releasing
bracket (11). Install washers (12) and nuts (13). truck for service. Check hydraulic tank oil level; oil
Do not tighten nuts to final torque at this time. must be visible in sight glass (4, Figure 3-4).

Filter Element Replacement
1. Place filter assembly (Figure 3-8) on work bench. 3. Install new element (2) into filter housing (1) using
Using a spanner tool at both ends, hold housing new O-Ring (3) and Backup Ring (4).
(1) and loosen (counter-clockwise) inlet housing
4. Install inlet housing (5) to filter housing (1) and
(5).
tighten to 10 - 12 kg.m (73 - 87 ft. lbs.) torque.
Remove inlet and then remove filter element (2)
from housing. Discard O-Ring (3) and Backup 5. Refer to "Filter Assembly Installation" and install on
Ring (4). truck.
2. Thoroughly clean filter housing and inlet housing. NOTE: Filter Elements should be replaced every 2000
Using clean hydraulic oil, lightly lubricate sealing hours* , and after any debris-producing component
surfaces. failure within the hydraulic system.
* More frequent replacement may be required in very
dusty/dirty environments.
FIGURE 3-8. FILTER ASSEMBLY

1. Filter Housing 3. O-Ring 5. Filter Housing Inlet 7. Spanner Hole
2. Filter Element 4. Backup Ring 6. Spanner Hole

NOTES

STEERING CIRCUIT
FIGURE 4-1. STEERING SYSTEM COMPONENTS

1. Tire 4. Crossover Relief Valve 7. Knuckle P: . . . From Demand Valve
2. Steering Cylinder 5. Steering Wheel 8. Arm (A-Frame) T: . . . To Hydraulic Tank
3. Tie Rod 6. Steering Control Valve LS: . . To Demand Valve
STEERING CIRCUIT OPERATION

The steering system is a self-metering, power steering The truck is also equipped with an automatic emer-
type. When the steering wheel (5, Figure 4-1) is rotated, gency steering system to provide oil pressure to the
the steering control valve (6) is actuated causing the steering circuit in the event of a loss of oil supply from
oil to flow into the steering cylinder (2). Extending one the engine driven steering pump. Refer to page L4-12
steering cylinder while retracting the opposite steering for a description of the emergency steering system
cylinder will change the angle of the front wheels, components.
allowing the operator to steer the truck as desired. The Additional information describing steering circuit op-
tie rod (3), attached to the knuckle (7) maintains a eration can be found in the description of the following
constant angular relationship between the left and right system components.
wheels.
L04017 12/98 Steering Circuit L4-1

DEMAND VALVE STEERING CONTROL VALVE
The demand valve (Figure 4-2) divides the oil sent from The steering control valve (Figure 4-3) is mounted
the steering pump and the hoist pump sending it to the under the cab floor and is connected to the steering
proper circuit according to a pressure signal received column by a short drive shaft.
from the steering control valve. If the operator is raising
When the operator rotates the steering wheel, steering
the dump body and no steering is required, all oil is
circuit oil is directed through the crossover relief valve
directed to the hoist circuit. When steering is required,
manifold to the steering cylinders.
the amount of oil needed to steer the truck is directed
to the steering valve. Pages L4-4 through L4-11 describe the various operat-
ing conditions of both the steering control valve and
the demand valve.
FIGURE 4-2. DEMAND VALVE ASSEMBLY FIGURE 4-3. STEERING CONTROL VALVE
ASSEMBLY
A: . . . . To Steering Valve P: . . . . From Demand Valve

B: . . . To Hydraulic Tank T: . . . . To Hydraulic Tank
C: . . . Emergency Steering Pump Port LT: . . . To Steering Cylinder
D: . . . . To Hoist Valve R: . . . . To Steering Cylinder
E: . . . . From Steering Valve (LS Port) LS: . . . To Demand Valve
F: . . . . From Steering Pump
G: . . . From Hoist Pump
L4-2 Steering Circuit L04017 12/98

HYDRAULIC SCHEMATIC
FIGURE 4-4. CROSSOVER RELIEF VALVE ASSEMBLY

A: . . . To Steering Cylinder 1. Releif Valve Assembly
B: . . . . To Steering Cylinder Tightening Torque 11 ± 1.5 kg.m (80 ± 10 ft. lbs.)
C: . . . . From Steering Valve 2. Valve Body
D: . . . . From Steering Valve
CROSSOVER RELIEF VALVE

The steering system crossover relief valve (Figure 4-4) The relief valves allow oil to escape from the steering
provides protection against excessive pressure in the cylinders if pressure exceeds 240 kg/cm2 (3400 psi).
steering circuit if an external force is applied to the front
wheels and the steering cylinders.

OPERATION OF DEMAND AND
STEERING CONTROL VALVE
STEERING CONTROL VALVE: When steering DEMAND VALVE: When steering valve is at
valve is at neutral neutral
The oil from the pump passes through the demand The oil from the steering pump enters port (A, Figure
valve and enters port P of the steering valve. 4-5). At the same time, the oil from the hoist pump
enters port B. When the steering valve is at neutral, port
Valve spool is at the neutral position, so port P and
P of the steering valve is closed, so the pressure at port
ports (RT and LT) to the cylinder are closed. No oil flows
P rises. The pressure from port P passes through orifice
to the cylinder, so the cylinder does not move.
“F” enters the chamber C, and moves spool (7) to the
At the same time, port LS is connected through port R right.
to the tank. As a result, there is no oil pressure at port
Port LS and chamber D are connected to the tank, and
LS, so all the oil from the pump at the demand valve
the force moving spool (7) to the left is the force of
flows to the hoist valve.
spool return spring (6). The pressure in chamber C
rises until it overcomes the set pressure of spool return
spring (6). As a result, spool (7) stops in the position
shown in the diagram, and all the oil from the steering
pump and hoist pump flows to the hoist valve.
When the steering valve is operated:

When the steering is operated, port P and port LS are
connected, and the circuit between the tank and port
LS is shut off. The hydraulic pressure before entering
the orifice of the steering valve acts on chamber C of
spool (7), and the hydraulic pressure coming out from
the orifice acts on chamber D.
There is a difference in the area of the opening of the
steering valve orifice when the steering is turned
quickly and when it is turned slowly. Therefore, the
hydraulic pressure on both sides of the orifice also
changes and a pressure difference is created. In this
way, spool (7) is actuated by the balance of the force
of return spring (6) and the differential pressure be-
tween both sides of the steering valve orifice. In other
words, it moves according to the balance of the oil
pressure in chamber C pushing to the right, and the
pressure of the oil in chamber D and return spring (6)
pushing to the left. The larger the difference in oil
pressure at the steering valve orifice, the less distance
the spool will travel to the left.

FIGURE 4-5. DEMAND AND STEERING VALVE NEUTRAL
1. Demand Valve 6. Spring 10. Steering Cylinders A: From Steering Pump
2. Check Valve 7. Spool 11. Crossover Relief Valve B: From Hoist Pump
3. Emergency Steering Pump 8. Relief Valve 12. Steering Control Valve C: Chamber
4. Hoist/Steering Pump 9. Relief Valve 13. Spool D: Chamber
5. To Hoist Valve E: Orifice
F: Orifice

STEERING CONTROL VALVE: When steering DEMAND VALVE: When steering wheel is
wheel is operated slowly to the right. operated slowly to the right.
When the steering wheel is turned slowly to the right The area of the opening of the steering valve orifice is
(Figure 4-6), input shaft rotates. When this happens, small, so the difference in pressure between the two
valve spool moves down. So when input shaft rotates, sides of the orifice is large. As a result, the movement
the oil from the demand valve flows into port P when the steering wheel is operated slowly to the right,
the spool moves a short distance to the left, and some
The oil inside the valve spool then passes between the
of the oil from the steering pump flows to the steering
stator and rotor in the metering portion of spool valve.
valve. The remaining oil from the steering pump and all
After the amount of oil flowing to the steering cylinder the oil from the hoist pump flows to the hoist valve.
is measured here, it enters the inside of the valve spool,
passes through a hole in the valve spool through port
RT and flows to the steering cylinders.
In this way, the two cylinders are actuated and the
wheels turn to the right.
The oil returning from the steering cylinder flows from
port LT and goes back to the tank.
The demand spool is actuated by the difference in
pressure between the oil pressure at port P end and
the oil pressure at the port LS end. As a result, only the
necessary amount of oil flows to the steering circuit,
and remaining oil flows from the demand valve to the
hoist valve.

FIGURE 4-6. STEERING SLOWLY RIGHT
5. To Hoist Valve

STEERING CONTROL VALVE: When steering DEMAND VALVE: When steering wheel is
valve is operated quickly to the left. operated quickly to the left.
When the steering wheel is turned quickly to the left The area of the opening of the steering valve orifice is
(Figure 4-7), input shaft rotates. When this happens, large, so the difference in pressure between the two
valve spool moves up. The oil from the demand valve sides of the orifice is small, therefor the difference at
flows into port P, through a hole in the valve spool, and chamber C and D is also small. As a result, spring (6)
enters the inside of the valve spool. moves spool (7) a long distance to the left, and all the
oil from the steering pump together with some of the
The oil inside the valve spool then passes between the
oil from the hoist pump passes through check valve (2)
stator and rotor in the metering portion of the valve.
and flows to the steering valve to provide a large
After the amount of oil flowing to the steering cylinder amount of oil to the steering valve.
is measured here, it flows through port LT and flows to
the steering cylinders.
In this way, two cylinders are actuated and the wheels
turn to the left.
The oil returning from the steering cylinder flows from
port RT and goes back to the tank.
The demand spool is actuated by the difference in
pressure between the oil pressure at port P end and
the oil pressure at the port LS end. As a result, only the
necessary amount of oil flows to the steering circuit,
and remaining oil flows from the demand valve to the
hoist circuit.

FIGURE 4-7. STEERING QUICKLY TO LEFT
5. To Hoist Valve

DEMAND VALVE: When in emergency steering STEERING CONTROL VALVE: When in
mode. emergency steering mode.

FIGURE 4-8. EMERGENCY STEERING MODE
5. To Hoist Valve E: Orifice
F: Port

FIGURE 4-9. EMERGENCY STEERING SYSTEM COMPONENTS
1. Batteries 6. Steering Pump
2. Emergency Relay Switch 7. Check Valve
3. Delay Timer 8. Demand Valve
4. Emergency Steering Switch 9. Emergency Steering Pump
5. Flow Switch 10. Hydraulic Oil Tank
EMERGENCY STEERING SYSTEM

If a loss of oil from the steering system occurs, either A switch mounted on the console next to the operator
due to loss of engine power or a pump (6, Figure 4-9) can be used to activate the emergency steering system
malfunction, a flow switch (5) senses loss of oil flow if necessary to steer the truck when the engine is not
and sends an electrical signal to the delay timer (3). If operable. Use of the emergency steering system
oil flow is insufficient for more than 3 seconds, the should be limited to a maximum of 90 seconds.
emergency steering motor relay switch (2) is ener- If necessary, the dump body may be raised using the
gized. When the relay is energized, the emergency emergency steering system.
steering system pump motor turns on and drives the
emergency steering pump (9). The operator can then
safely steer the truck out of traffic and shut down the
truck for system repairs.

FIGURE 4-10. EMERGENCY STEERING SYSTEM FLOW SWITCH
1. Reed Switch 3. Spring 5. Magnet
2. Pivot Pin 4. Plate
FLOW SWITCH
The flow switch (Figure 4-10) is installed in the steering
circuit piping to monitor steering circuit oil flow.
Operation
Refer to “A”, Figure 4-10:
When oil is flowing in the pipe, plate (4) is pushed to
the left, overcoming spring (3) force and the lever
pivots on pin (2). The magnet (5) mounted on the lever
moves away from the reed switch and opens the con-
tact.
Refer to “B”, Figure 4-10:
When oil flow is interrupted, the lever pivots in the
opposite direction due to spring (3). Magnet (5) moves
close to the reed switch contacts closing the electrical
circuit. This electrical signal is routed to the relay timer
below.
Relay Timer
The relay timer provides an electrical delay in the circuit
between the flow switch and the emergency steering
pump motor relay. The timer is adjusted to provide a 3
second delay to prevent accidental actuation of the
emergency steering system due to slight interruptions FIGURE 4-11. RELAY TIMER
in oil flow. Refer to Figure 4-12 for electrical schematic. 1. Timer Assembly 2. Delay Adjustment Knob

FIGURE 4-12. EMERGENCY STEERING SYSTEM
ELECTRICAL SCHEMATIC

STEERING VALVE ASSEMBLY
Removal 5. Mark location of each hose attached to steering
valve assembly ports. (Note: each port is marked
1. Loosen the oil filler cap slowly to release the
with a letter.) Disconnect 5 hoses (2). Cap all
pressure inside the hydraulic tank.
openings to prevent contamination and excessive
2. Pass a rope through the yoke and secure the yoke leakage.
to the top to prevent the yoke from falling out from
6. Remove capscrews (3, Figure 5-2) retaining steer-
the column shaft spline.
ing valve assembly to mounting bracket (4).
3. Make match marks to show the position of inser-
7. Lower the assembly from the bracket.
tion for the spline at the steering wheel and yoke
as shown in Figure 5-2. (This will allow proper
Installation
reassembly in case splines must be separated.)
1. Raise the steering control valve into position,
4. Remove yoke lock bolt (1, Figure 5-1) The lock bolt
aligning spline match marks made prior to re-
has a fine thread; be careful not to lose it or
moval if the lower shaft was not removed.
damage the thread.
a. Check that the yoke moves up and down easily 2. Attach steering control valve to mounting bracket
on the spline of the steering valve input shaft, using capscrews (3, Figure 5-2). Tighten cap-
and that it comes off easily. screws to standard torque. If the shaft (4, Figure
5-1) has not been disassembled, attach the yoke
NOTE: If yoke cannot be easily removed from the input to the input shaft splines. Insert the lock bolt (1)
shaft, it may be necessary to remove the steering valve and tighten to standard torque.
assembly and lower shaft as a unit by disengaging the
splines. 3. Remove caps and plugs and attach hoses (2,
Figure 5-1) to the correct ports.
b. Do not use excessive force removing the yoke
as the input shaft can be damaged. 4. Verify all hydraulic and mechanical connections
are secure.
5. Verify proper operation of steering system com-
ponents.
FIGURE 5-1.
1. Lock Bolt 3. Steering Valve Assy. FIGURE 5-2.
2. Hoses 4. Column Shaft 1. Yoke 3. Capscrews
2. Steering Valve Assy. 4. Mounting Bracket
L05011 Steering Valve Assembly L5-1

Disassembly
• When carrying out maintenance of the power
steering system, cleanliness is absolutely essen-
tial. The hydraulic circuit must be completely iso-
lated from any dirt or dust.
• If it is necessary to disassemble any part of the unit,
always use a clean work stand.
• Before disconnecting any piping, always wipe off
all the dirt on the outside.
• Before setting the unit on the work stand, always
wipe off any dirt on the outside.
• After disassembly, clean with a petroleum base FIGURE 5-4. COMMUTATOR REMOVAL
solvent that is free from any impurity, then blow 1. Commutator 2. Valve Assembly
with dry air that is free from any impurity.
1. Remove 7 mounting bolts (5, Figure 5-3), then

If any other solvent is used, it may cause deterio- insert screwdriver between end cover assembly
ration of the rubber seal. Do not wipe any part with (4) and sleeve (3), and remove end cover assem-
a cloth or apply hot air to the unit. bly. After removing, check for any breakage
around the edge of the end cover hole.
The solvent is a flammable substance, so be care-
ful to handle it correctly and do not bring any flame 2. Remove commutator (1, Figure 5-4) and washer
close to it. (2, Figure 5-5). Do not remove pin (1).
Preparation
• Fit blind plugs to 5 ports of the valve body, clean
the outer parts, then remove the blind plugs.
• Install tube nut (2, Figure 5-3) to one of the ports.
• Install in vice (1) with the end cover facing up.
• Do not hold the valve body directly in the vice. This
may cause damage to the unit.
FIGURE 5-5.
1. Pin 2. Washer
FIGURE 5-3. END COVER REMOVAL

1. Vise 3. Sleeve
2. Tube Nut 4. End Cover
5. Bolts
L5-2 Steering Valve Assembly L05011

FIGURE 5-6. COMMUTATING RING REMOVAL FIGURE 5-8. SLEEVE REMOVAL
1. Mounting Bolts 3. Manifold 1. Sleeve 2. Valve Body
2. Commutator Ring 4. Rotor Set
3. Using 2 mounting bolts (1, Figure 5-6), remove 5. Insert screwdriver between sleeve (1, Figure 5-8)
commutator ring (2) and manifold (3). and valve body (2), and remove sleeve .
4. Using 2 mounting bolts, remove rotor set (4, Figure 6. Remove drive link (1, Figure 5-9).
5-7) and wear plate (1) in the same way as com-
mutator ring and manifold.
FIGURE 5-7. ROTOR SET REMOVAL FIGURE 5-9. DRIVE LINK REMOVAL
1. Wear Plate 3. Manifold 1. Drive Link 2. Valve Body
2. Commutator Ring 4. Rotor Set

FIGURE 5-12.
1. Input Shaft 3. Valve Body
FIGURE 5-10. BALL REMOVAL 2. Upper Cover 4. Mounting Bolt
1. Ball 2. Valve Body
9. Install in vice so that input shaft (1, Figure 5-12)
faces up, then make match marks with a punch in
upper cover (2) and valve body (3).
10. Remove 4 mounting bolts (4), hold input shaft (1)
and move it up, then remove input shaft, upper
7. Remove ball (1, Figure 5-10).
cover, and valve spool assembly (1, Figure 5-13).
8. Remove rod (1, Figure 5-11), roller (2), rod (3), and
spring (4).
The valve spool is fitted into the body with an

extreme small clearance, so be careful not to apply
any sideways force as it will become impossible to
remove it. When removing the valve spool from the
housing, never use any excessive force.
FIGURE 5-11.
1. Rod 3. Rod
2. Roller 4. Spring
FIGURE 5-13.
1. Spool Assembly 2. Upper Cover

FIGURE 5-16.
1. Snap Ring 4. Thrust Washer
FIGURE 5-14. 2. Thrust Washer 5. Wave Washer
1. Shims 2. Spacer 3. Thrust Bearing 6. Input Shaft
11. Remove upper cover assembly from input shaft

and valve spool assembly, then remove shim (1,
Figure 5-14) and spacer (2).
NOTE: Check the number and thickness of the shims,
and keep in a safe place.
FIGURE 5-17. PIN REMOVAL

1. Punch 2. Input Shaft
FIGURE 5-15.
1. Snap Ring 4. Seal Ring
2. Spacer 5. Upper Cover
3. Seal
12. Remove seal (6, Figure 5-15) and snap ring (1), then
remove spacer (2), seal (3), and seal ring (4) from
upper cover (5).
NOTE: Seal (3) and seal ring (4) may be combined into
one piece.
13. Remove snap ring (1, Figure 5-16), thrust washer
(2), thrust bearing (3), thrust washer (4), and wave
washer (5) from input shaft (6).
14. Using a punch (1, Figure 5-17) 3.0 mm dia., x 16
mm long (.12 in. dia. x .62 in. long), remove pin (2,
Figure 5-18) from input shaft. FIGURE 5-18. PIN DETAIL
1. Shaft 2. Pin
NOTE: To prevent damaging the input shaft, carry out
the operation on a wooden block.

FIGURE 5-21. BALL REMOVAL
FIGURE 5-19. 1. Valve Spool 3. Drive Link
1. Spool 3. Spacer 2. Input Shaft 4. Ball
2. Torsion Bar 4. Pin
17. Set valve spool (1, Figure 5-21) facing down, then
15. Set valve spool (1, Figure 5-19) facing down, then rotate input shaft (2) clockwise until ball (4) comes
remove torsion bar (2) and spacer (3) from input out.
shaft and valve spool assembly.
NOTE: Do not remove ball retaining spring (1, Figure
16. Set valve spool (1, Figure 5-20) facing down, then 5-22) unless replacing it. When removing it, make the
rotate input shaft (2) until drive link (3) comes out. end horizontal, grip it with pliers, then pull it up until it
comes completely away from valve spool (2). Be care-
ful not to damage the control edge or outside circum-
ference of the valve spool.
FIGURE 5-22.
1. Ball Retaining Spring 2. Valve Spool
FIGURE 5-20. DRIVE LINK REMOVAL

1.Valve Spool 3. Drive Link
2. Input Shaft

Assembly
• Before assembling, wash all parts in clean petro-
leum base solvent, then dry with air. Never wipe
with a cloth.
• Check that there are no pieces of paint remaining
on the edge of the lapped surface.
• Unless there are special instructions, do not coat
any part with oil when assembling.
FIGURE 5-25.
1. Set thrust washer (1, Figure 5-23), thrust bearing
1. Wave Washer 3. Thrust Bearing
(2), and thrust washer (1, Figure 5-24) on input
2. Thrust Washer
shaft, and install snap ring (2).
FIGURE 5-23.
1. Thrust Washer 3. Input Shaft FIGURE 5-26. BALL INSTALLATION
2. Thrust Bearing 1. Ball 2. Valve Spool
2. Install wave washer (1, Figure 5-25) to thrust 4. Rotate counterclockwise so that ball and groove
bearing (3) and thrust washer (2). are meshed, and insert input shaft (1, Figure 5-27)
in valve spool (2).
3. Install ball (1, Figure 5-26) on inside of valve spool
(2).
NOTE: Keep the spool horizontal when carrying out the
operation.
FIGURE 5-24.
1. Thrust Washer 2. Snap Ring
FIGURE 5-27. INPUT SHAFT INSTALLATION

1. Input Shaft 2. Valve Spool

FIGURE 5-30.
1. Spool 3. Drive Link
2. Input Shaft
FIGURE 5-28.
1. Valve Spool 3. Thrust Washer
2. Torsion Bar
5. Fit middle of torsion bar (2, Figure 5-28) between

thrust washer (3) and valve spool (1). If the spool, drive link, and input shaft are not
correctly installed in relation to each other, the
NOTE: The positioning of the valve spool and input
steering unit will not work properly.
shaft is carried out by fitting the torsion bar.
7. Measure diameter “A” of pin (1, Figure 5-31) of
6. Check spline of drive link (1, Figure 5-29) and input
torsion bar (2) at several places, and check that
shaft (2), then align spline of valve spool (3), and
the difference is less than 0.025 mm (.001 in.).
install drive link.
NOTE: If the drive link and input shaft spline do not
mesh, rotate the input shaft slightly to mesh them.
When inserting the drive link, fit the torsion bar se-
curely.
If the drive link is assembled correctly, a clearance of
8.89 mm (.350 in.) will be obtained between the thrust
washer and valve spool.
FIGURE 5-31. PIN MEASUREMENMT

1. Pin 2. Torsion Bar
FIGURE 5-29.
1. Drive Link 3. Spool
2. Input Shaft

FIGURE 5-32.
1. Pin 3. Spacer FIGURE 5-34.
2. Torsion Bar 4. Spool & Input Shaft 1. Torsion Bar 2. Pin
8. Set spacer (3, Figure 5-32) to torsion bar (2), and 11. Install spacer (1, Figure 5-35) on input shaft and
insert valve spool and input shaft assembly (4). valve spool.
9. Using punch (1, Figure 5-33) (outside diameter: 3
mm (.12 in.)), align pin holes of torsion bar and
NOTE: If there is a lip at one end on the inside of the
input shaft (2).
spacer, install with the lip surface facing the wave
10 Using above punch, drive pin (2, Figure 5-34) in 0.8 washer.
mm (.031 in.) from end face of input shaft.
FIGURE 5-35.
1. Spacer 2. Spool Assembly
FIGURE 5-33. PIN INSTALLATION

1. Punch 2. Input Shaft

FIGURE 5-36.
1. Valve Spool Assembly 3. Shim
2. Valve Body FIGURE 5-38.
1. Tool (790-452-1200) 2. Upper Cover
12. Install input shaft and valve spool assembly (1, 16. Measure width of groove of drive link (1, Figure
Figure 5-36) to valve body (2). 5-39) at several places, and check that the differ-
ence is less than 0.025 mm (.001 in.).
13. Set shim (3) on thrust washer, then fit seal, align
match mark of upper cover (2, Figure 5-37) and 17. Pull input shaft down, align drive link (1) with valve
install the mounting bolts (4) temporarily. spool spline, and install. Rotate spool so that valve
body is level with end face of spool.
14. Set tool (1, Figure 5-38) in position, and install so
that valve body and upper cover are centered.
15. Tighten mounting bolts (4, Figure 5-37), and re-
move special tool.
FIGURE 5-37. UPPER COVER INSTALLATION FIGURE 5-39. DRIVE LINK INSTALLATION
1. Valve Spool 3. Valve Body 1. Drive Link 2. Valve Body
2. Upper Cover 4. Bolt

FIGURE 5-40. DRIVE LINK INSTALLATION FIGURE 5-42. MEASURING MOUNTING HEIGTH
1. Drive Link 2. Pin 1. Micrometer 2. Drive Link
18. Align drive link (1, Figure 5-40) and pin (2), then 20. Install ball (1, Figure 5-43).
install.
21. Set rod (2) to spring (3), and fit to valve body (6),
19. Using depth micrometer (1, Figure 5-42), measure then install roller (4) and rod (5).
mounting height “h” ( See Figure 5-41) of end face
22. Fit seal to valve body.
of valve spool and valve body.
• Mounting height “h” = Within 0.063 mm (.002 in.)
NOTE: If mounting height “h” = 0.064 mm (.003 in.) or

more, repeat steps 12 - 19 and adjust the shims to make
“h” = within 0.063 mm (.002 in.).
FIGURE 5-43.
FIGURE 5-41. 1. Ball 4. Roller
1. Drive Link 2. Valve Body 2. Rod 5. Rod
3. Spring 6. Valve Body

FIGURE 5-44. ROTOR INSPECTION
1. Rotor Assembly 2. Stator
23. Before installing rotor, inspect rotor as follows.

a. Set pin side of end cover assembly facing up, FIGURE 5-46.
and spline side of rotor assembly (1, Figure 1. Guide Pin 2. Wear Plate
5-44) facing down, and check that the rotor
rotates freely inside the stator (2).
24. Using guide pin (1, Figure 5-46), install wear plate
b. Measure thickness of rotor and stator, and
(2), rotor assembly (5, Figure 5-47), and manifold
check that difference is within 0.18 mm (.007
(4).
in.).
c. Using feeler gauge (1, Figure 5-45) check that 25. Fit seal to end cover assembly (1).
clearance of rotor from stator is within 0.18 mm 26. Set sleeve (2) and end cover assembly (1) in
(.007 in.). position, then tighten mounting bolts (3) uniformly
and install sleeve, then remove end cover assem-
bly.
FIGURE 5-45. ROTOR CLEARANCE

1. Feeler Gauge 3. Stator
2. Rotor
FIGURE 5-47. SLEEVE INSTALLATION

1. Cover Assembly 5. Rotor Assembly
2. Sleeve 6. Wear Plate
3. Bolt 7. Wear Plate
4. Manifold

FIGURE 5-48.
1. Cover Assembly 2. Washer
27. Fit washer (2, Figure 5-48) to end cover assembly

(1), and install commutator (1, Figure 5-49). FIGURE 5-50.
NOTE: Install the commutator with the concave part 1. Commutator 3. Drive Link
facing the end cover assembly side. Position so that 2. Manifold 4. Sleeve
the hole in the oval commutator is in a straight line with
one of the bolt holes in the end cover assembly.
28. Install commutator ring (1, Figure 5-49).
29. Rotate input shaft so that tip of drive shaft is aligned
with oval hole in commutator. (See Figure 5-50)
30. Set end cover assembly (2, Figure 5-51) on sleeve
(3), then tighten 5 mounting bolts (1) uniformly.
Tighten to standard torque.
FIGURE 5-49.
1. Commutator 2. Valve Assembly
FIGURE 5-51. END COVER INSTALLATION
1. Bolt 3. Sleeve
2. End Cover 4. Valve Body

FIGURE 5-53. SPACER INSTALLATION
1. Spacer Installation Tool. 2. Spacer
(790-452-1100)
FIGURE 5-52. SEAL ASSEMBLY INSTALLATION
1. Seal Ring 4. Seal
2. Seal 5. Spacer
3. Snap Ring
31. Set input shaft end facing up, then install seal ring 32. Using tool (1, Figure 5-53), install spacer (2) from
(1, Figure 5-52) and seal (2). small diameter end.
NOTE: Install the seal from the small diameter end. Seal 33. Install snap ring (3, Figure 5-52).
ring (1) and seal (2) are supplied stuck together as one
34. Fit seal (4) to input shaft, and install to upper cover.
unit. Coat the new seal with oil, and install it from the
lip end; - When doing this, coat thinly with grease.

STEERING CIRCUIT COMPONENT REPAIR
EMERGENCY STEERING MOTOR PUMP
ASSEMBLY
Removal
Disconnect the cable from the negative (-) terminal
of the battery.
1. Drain hydraulic oil. FIGURE 6-1. EMERGENCY STEERING PUMP

MOTOR
2. Disconnect motor wiring (1, Figure 6-1).
1. Motor Wiring 2. Steering Motor Pump
3. Remove tube (2, Figure 6-2).
Assembly
4. Remove hose (3).
5. Remove emergency steering motor pump assem-
bly.
Note: Remove the emergency steering motor pump
assembly together with bracket.
Installation
1. Lift emergency steering motor pump assembly
and bracket into position.
2. Install hose (3, Figure 6-2).
3. Install tube (2).
4. Connect motor wiring (1, Figure 6-1). FIGURE 6-2. PUMP PIPING
1. Steering Motor Pump 2. Tube
5. Refill oil to the specified level and run the engine
Assembly 3. Hose
to circulate the oil through the system. Then check
the oil level again.
L06009 Steering Circuit Component Repair L6-1

STEERING CYLINDER ASSEMBLY
Removal
1. Disconnect grease tube (1, Figure 6-3).
2. Remove head pin (2).
NOTE: Support with a transmission jack. Start the

engine and operate the steering to retract the piston
rod, then disconnect the cylinder bottom from the
frame.
FIGURE 6-3. STEERING CYLINDER PIPING
1. Grease Tube 3. Head Hose
3. Remove head hose (3, Figure 6-3). 2. Head Pin 4. Rod Hose
4. Remove rod hose (4).
5. Disconnect grease tube (2, Figure 6-4).
6. Remove rod pin (3).
7. Remove steering cylinder assembly (1).
Installation
1. Lift steering cylinder (1, Figure 6-4) into position.
Position rubber boot (1, Figure 6-5) and install
head pin (2, Figure 6-3). Install pin retaining cap-
screw with washer and tighten to standard torque.
2. Position piston rod eye in bracket bore. Install
rubber boot (1, Figure 6-5) and pin. Install pin
retaining capscrew with washer and tighten to FIGURE 6-4. STEERING CYLINDER INSTALLATION
standard torque. 1. Steering Cylinder 3. Rod Pin
2. Grease Tube
3. Connect grease tubes (2, Figure 6-4 & 1, Figure
6-3).
4. Install rod hose (4, Figure 6-3).
5. Install head hose (3).
FIGURE 6-5. TYPICAL MOUNTING PIN

1. Rubber Boot 2. Pin
L6-2 Steering Circuit Component Repair L06009

Disassembly
Tools needed for rebuilding steering cylinder:
a. 790-502-1003 cylinder repair stand
790-502-2000 cylinder repair stand
b. 790-102-3802 wrench assembly
790-102-3791 wrench assembly
c. 790-302-1340 40 mm six point socket
d. 790-720-1000 ring expander
e. 790-720-1660 ring compressor
1. Set cylinder assembly (1, Figure 6-6) in rebuild
stand (3).
NOTE: If a rebuild stand is not available, place cylinder
on a suitable work bench. Be careful not to nick the
cylinder rod.
FIGURE 6-7. ROD DISASSEMBLY

2. Raise lock of cylinder head nut, and using wrench 1. Rod Assembly 3. 40 mm socket
assembly (4), remove cylinder head assembly (2). 2. Rebuild Stand 4. Nut
3. Pull out cylinder head (7, Figure 6-8) and piston
rod assembly (4) from cylinder (12) and remove.
5. Disassembly of piston rod assembly

NOTE: When the piston rod assembly is pulled out from
a. Set piston rod assembly (1, Figure 6-7) in re-
the cylinder, oil will come out, so catch it in a container.
build stand.
b. Using a 40 mm socket (3), remove nut (4).
4. Remove cylinder from rebuild stand. c. Remove piston assembly (1, Figure 6-8) and
cylinder head assembly (2) from rod (3).
FIGURE 6-6. CYLINDER DISASSEMBLY

1. Cylinder Assembly 3. Rebuild Stand FIGURE 6-8. ROD DISASSEMBLY
2. Cylinder Head 4. Wrench Assembly 1. Piston Assembly. 3. Rod
2. Cylinder Head Assembly.

FIGURE 6-9. STEERING CYLINDER ASSEMBLY
1. Snap Ring 5. Snap Ring 9. Rod Packing 13. Piston
2. Bushing 6. Dust Seal 10. Backup Ring 14. Piston Ring
3. O-Ring 7. Cylinder Head 11. O-Ring 15. Wear Ring
4. Piston Rod 8. Bushing 12. Cylinder 16. Nut
6. Disassembly of piston. a. Remove snap ring (7, Figure 6-11), then remove
a. Remove wear ring (1, Figure 6-10) from piston dust seal (6).
(2). b. Remove rod packing (4).
b. Remove piston ring (3) from piston (2). c. Remove bushing (5) from cylinder head (1).
7. Disassembly of cylinder head assembly d. Remove O-ring (3) and backup ring (2).
FIGURE 6-10. PISTON DISASSEMBLY FIGURE 6-11. CYLINDER HEAD DISASSEMBLY

1. Wear Ring 3. Piston Ring 1. Cylinder Head 5. Bushing
2. Piston 2. Backup Ring 6. Dust Seal
3. O-Ring 7. Snap Ring
4. Rod Packing

FIGURE 6-13. ROD PACKING INSTALLATION
1. Rod Packing 2. Cylinder Head
FIGURE 6-12. CYLINDER HEAD ASSEMBLY

d. Using push tool, install dust seal (6) to cylinder
1. Cylinder Head 5. Bushing
head (1), then install snap ring (7).
2. Backup Ring 6. Dust Seal
3. O-Ring 7. Snap Ring
4. Rod Packing 2. Piston assembly
a. Using ring expander (1, Figure 6-14), expand
piston ring (2).
Assembly
NOTE: Clean all parts, and check for dirt or damage. NOTE: Set the piston ring on the expander and turn the
Coat the sliding surfaces of all parts with engine oil handle 8 - 10 times to expand the ring.
before installing.
1. Cylinder head assembly.

a. Using push tool, press fit bushing (5, Figure
6-12) in cylinder head (1).
Be careful not to deform the bushing when press

fitting.
b. Install rod packing (4).

NOTE: Be careful to install the rod packing facing in the
correct direction as shown in Figure 6-13.
FIGURE 6-14. PISTON RING EXPANDER
c. Assemble backup ring (2) and O-ring (3) in
order. 1. Ring Expander 2. Piston Ring
790-720-1000
NOTE: Do not try to force the backup ring into position.
Warm it in warm water 50° - 60° C (122° - 140° F) before
installation.

FIGURE 6-17. ROD ASSEMBLY
1. Piston Assy. 3. Rod
2. Cylinder Head Assy.
FIGURE 6-15. PISTON ASSEMBLY

1 Wear Ring 3. Piston Ring
2. Piston
b. Remove piston ring from tool, and assemble to 3. Piston rod assembly
piston (2, Figure 6-15). a. Assemble cylinder head assembly (2, Figure
c. Set ring compressor (2, Figure 6-16) in position, 6-17) and piston assembly (1) to piston rod (3).
and using a hose clamp (1), compress piston b. Coat threads with Loctite and using 40 mm
ring. socket (3, Figure 6-18) tighten nut (4) to 405
d. Assemble wear ring (3, Figure 6-15). ± 40.5 kg.m (2929 ± 29.2 ft. lbs.) torque.
c. Remove piston rod assembly (3) from tool.
FIGURE 6-16. COMPRESSING PISTON RING FIGURE 6-18. ROD ASSEMBLY

1. Clamp 2. Ring Compressor 1. Rod Assembly 3. 40 mm Socket
790-720-1660 2. Rebuild Stand 4. Nut

DEMAND VALVE ASSEMBLY
Removal
Loosen the oil filter cap slowly to release the pres-
sure inside the hydraulic tank.
NOTE: After disconnecting the piping, plug all open-
ings to prevent oil from leaking.
1. Remove tubes (1, Figure 6-20)
2. Remove hoses (2).
FIGURE 6-19. CYLINDER ASSEMBLY 3. Remove demand valve assembly (3).
1. Cylinder Assembly 3. Rebuild Stand
2. Cylinder Head 4. Wrench Assembly Installation
1. Install demand valve (3, Figure 6-20).
4. Set cylinder in rebuild stand (3, Figure 6-19).
2. Remove plugs and install hoses (2).
5. Assemble cylinder head (2) and piston rod assem-
3. Remove plugs and install tubes (1).
bly in cylinder (1).
4. Refill oil to the specified level and run the engine
6. Using wrench assembly (4), tighten cylinder head
to circulate the oil through the system. Then check
assembly (2). to 95 ± 9.5 kg.m (687 ± 68.7 ft.
the oil level again.
lbs.) torque.
5. Bleed air from system.
FIGURE 6-20. DEMAND VALVE INSTALLATION

1. Tubes 3. Demand Valve
2. Hose

FIGURE 6-21. DEMAND VALVE ASSEMBLY
1. Valve Body 4. Plate 7. Poppet 10. Plate
2. Cover 5. Plug 8. Plug 11. Orifice
3. Spring 6. Spring 9. Spool 12. Relief Valve Assy.
1. Remove cover (2, Figure 6-21) from valve body (1), 1. Fit backup ring and O-ring and install relief valve
then remove spring (3). assembly (12).
2. Fit backup ring and O-ring and assemble orifice
(11), then secure with plate (10).
3. Assemble demand spool (9), then fit O-ring and
tighten plug (8).
The spring (3) is under an installed load of 35 kg.
(77 lbs.). Remove slowly using several long bolts. 4. Assemble poppet (7) and spring (6), then fit
backup ring and O-ring and install plug (5), then
2. Remove plate (4), screw bolts into threaded end
secure with plate (4).
of plug (5), and pull out plug, then remove spring
(6) and poppet (7). 5. Assemble spring (3), then fit O-ring and install
cover (2).
3. Remove plug (8), and pull demand spool (9) out.
4. Remove plate (10), screw bolts into threaded end
of orifice (11), and remove orifice.
5. Remove relief valve assembly (12).

FIGURE 6-22. RELIEF VALVE ASSEMBLY
1. Screw 5. Poppet 9. Spring
2. Nut 6. Nut 10. Valve
3. Retainer 7. Holder 11. Snap Ring
4. Spring 8. Seat
RELIEF VALVE ASSEMBLY
1. Loosen nut (2, Figure 6-22), and remove screw (1), 1. Assemble spring (9) and valve (10).
then remove retainer (3), spring (4), and poppet 2. Install snap ring (11).
(5).
3. Install backup ring and O-ring to seat (8).
2. Loosen nut (6), and remove holder (7), then pull
out seat (8). 4. Install O-ring to holder (7).
3. Remove snap ring (11), then remove valve (10) and 5. Assemble seat (8), then screw in holder (7), and
spring (9). secure with nut (6).
6. Install poppet (5), spring (4), and retainer (3).
7. Fit O-ring to screw (1), then screw in and secure
with nut (2).

NOTES

HOIST CIRCUIT OPERATION AND COMPONENT DESCRIPTION
HOIST CIRCUIT OPERATION The filter elements should be replaced every 1000
hours or when the filter warning light on the instrument
The hydraulic pump supplies oil to the demand valve. panel turns on.
After the steering circuit demand has been fulfilled, the
demand valve shifts the flow of hydraulic oil from the It is possible for the indicator light to turn on when oil
steering circuit to the hoist valve. in the system is cold. If this occurs, the light should turn
off when the hydraulic oil temperature reaches normal
operating temperature.
HOIST CIRCUIT COMPONENT
DESCRIPTION Hoist Valve
Hoist Cylinders The hoist valve spool has four positions; “RAISE”,
“HOLD”, “FLOAT”, and “POWER DOWN”. The posi-
The hoist cylinders are located on the outside of the tions are obtained by a combination of the detents,
frame just forward of the rear wheels. The hoist cylin- centering spring and lever position.
ders accomplish the dumping action of the body and
are three stage units. Hydraulic oil from the hoist pump It should be noted that, at all times, oil from the hoist
is routed to the demand valve and on to the hoist valve. pump has access to the relief valve. The valve is set to
The hoist valve controls the four positions of the hoist relieve pressure in excess of 210 kg.cm2 (3000 psi) to
cylinders; “DOWN”, “FLOAT”, “HOLD”, and “RAISE”. port “B” returning it to the tank.
Hydraulic Filter
Oil is filtered through a 30 micron filter to reduce the
possibilities of contamination to the hydraulic system.
L07010 Hoist Circuit Operation and Component Description L7-1

FIGURE 7-1. HOIST VALVE (RAISE POSITION)
1. Load Check Poppet A. Inlet

2. Spool B. Return
3. Detent Spring and Ball C. Power Down Port
4. Centering Spring D. Raise Port
RAISE
Movement of the hoist lever to the “RAISE” position The load check valve prevents oil from flowing out of
moves the spool valve to the end of the hoist valve. the raise side of the cylinders when the spool is moved
Refer to Figure 7-1. into and out of the “RAISE” position, thus preventing
the body from dropping.
Oil from the hydraulic pump enters port “A”. Because
the spool has blocked any further flow, the oil pressure
builds up until it opens the spring-loaded load check
valve to port “D”. The spool in the “RAISE” position
opens port “D” so oil is directed to the hoist cylinders,
through the “RAISE” line to extend the cylinders. The
return oil from the hoist cylinders goes into port “C”
past the spool to port “B” and to the hydraulic tank.
L7-2 Hoist Circuit Operation and Component Description L07010

FIGURE 7-2. HOIST VALVE (HOLD POSITION)

2. Spool B. Return
HOLD
Located just below the raise position is the hold posi- The oil in the hoist cylinders is blocked at port “C” and
tion. Moving the hoist lever down from the raise posi- port “D” by the spool which prevents cylinder move-
tion, along with the centering spring, returns the spool ment.
to the “HOLD” position. Refer to Figure 7-2.
Oil from the hoist pump enters port “A” and goes
around the spool to port “B” and returns to the tank.

FIGURE 7-3. HOIST VALVE (POWER DOWN POSITION)

2. Spool B. Return
POWER DOWN
Movement of the hoist lever to the “DOWN” position Oil at port “D” returns from the hoist cylinders and is
moves the spool to the non-detent end of the hoist open to port “B” back to the tank.
valve. This moves the spool to the “POWER DOWN”
position. Refer to Figure 7-3.
Oil from the hoist pump enters PORT “A” and is di-
rected to port “C” by the spool. The oil going out port
“C” goes to the hoist cylinders to retract them.

FIGURE 7-4. HOIST VALVE (FLOAT POSITION)

2. Spool B. Return
FLOAT
Moving the hoist lever to the “FLOAT” position, the Hoist cylinder port “C” is open to port “A” to allow oil
centering spring returns the spool to the “FLOAT” to flow to the lower areas between the cylinder stages.
position where the detent stops it. Refer to Figure 7-4.
The truck should always be operated on the haul road
Oil from the hoist pump enters port “A” and is directed with hoist control valve in the “FLOAT” position.
to port “B” by the spool and returns to the tank. The oil
in the hoist cylinders is also returned back to the tank
from port “D” to port “B”, due to the spool location.

NOTES

HOIST CIRCUIT COMPONENT REPAIR
HOIST VALVE ASSEMBLY
Loosen the oil filler cap slowly to release the pres-
sure inside the hydraulic tank.
Removal
1. Drain hydraulic oil.
2. Disconnect control cable (1, Figure 8-1)).
3. Remove bracket (2).
4. Disconnect positioner cable (3).
5. Remove spring (4).
6. Remove bracket (5). FIGURE 8-1. HOIST VALVE INSTALLATION
7. Remove hose (6). 1. Control Cable 6. Hose
2. Bracket 7. Tube
8. Remove tubes (7) and (8).
3. Positioner Cable 8. Tube
9. Remove hose (1, Figure 8-2). 4. Spring 9. Hoist Valve
5. Bracket
10. Remove hoist valve assembly (9, Figure 8-1).
Installation
1. Install hoist valve assembly.
2. Remove caps and plugs from hoses. Install hose
(1, Figure 8-2).
3. Install tubes (7 & 8, Figure 8-1).
4. Install hose (6).
5. Install bracket (5).
6. Install spring (4).
7. Install positioner cable (3).
8. Install bracket (2).
9. Install control cable (1).
10. Refill hydraulic tank oil to the specified level and FIGURE 8-2. HOSE REMOVAL & INSTALLATION
run the engine to circulate the oil through the 1. Hose 2. Bracket
system. Then check the oil level again.
L08010 Hoist Circuit Component Repair L8-1

Disassembly FIGURE 8-3. HOIST VALVE ASSEMBLY
1. Remove main relief valve assembly (1, Figure 8-3). 1. Main Relief Valve Assembly
2. Nut
2. Loosen nut (2), and remove screw (3), then r -
3. Screw
move retainer (4), spring (5), and poppet (6).
4. Retainer
3. Loosen nut (7), and remove holder (8) and seat 5. Spring
(9). 6. Poppet
7. Nut
4. Remove snap ring (10), then remove retainer (11),
8. Holder
valve (12), and spring (13) from sleeve (14).
9. Seat
5. Remove tube (15). 10. Snap Ring
11. Retainer
6. Remove case (16), and bolts (17), then remov
12. Valve
detent (18), collar (19), retainer (20), spring (21),
13. Spring
and retainer (22).
14. Sleeve
7. Remove valve control case assembly (23). 15. Tube
16. Case
8. Remove cover (24), then loosen bolt (25), mov
17. Bolt
lever (26), and remove key (27).
18. Detent
9. Remove plate (28), then remove dust seal (29), oil 19. Collar
seal (30), shaft (31), and bearing (32) from cas 20. Retainer
(33), and pull out spool (34). 21. Spring
22. Retainer
10. Remove plate (35), and seat (36), then remove
23. Valve Control Case Assembly
spring (37) and valve (38) from valve body (39).
24. Cover
25. Bolt
26. Lever
Assembly 27. Key
28. Plate
1. Insert valve (38) and spring (37) in valve body (39),
29. Dust Seal
then fit O-ring and assembly seat (36). Coat sur -
30. Oil Seal
face of plate (35) with Loctite and install.
31. Shaft
NOTE: Coat the parts in step 2. with Mobil Grease 32. Bearing
or equivalent lubricant prior to assembly: 33. Case
34. Spool
2. Press fit bearing (32), oil seal (30), and dust seal
35. Plate
(29) in case (33).
36. Seat
3. Insert shaft (31), assemble key (27) and lever (26), 37. Spring
then align position of notch in spool (34) with lever 38. Valve
(26), and secure with bolt (25). 39. Valve Body
4. Coat surface of plate (28) and cover (24) with
Loctite and install.
5. Insert spool (34). Coat surface of valve control
case assembly (23) with Loctite and install.
9. Assemble spring (13), valve (12), and retainer (11)
6. Assemble retainer (22), spring (21), retainer (20), in sleeve (14), then fit snap ring (10) and install
collar (19), and detent (18), then tighten bolt (17) seal (9), holder (8), and nut (7). Tighten nut (7) to
to standard torque. standard torque.
7. Coat mating surface of case (16) with Loctite. Fit 10. Install poppet (6), spring (5), retainer (4), screw (3),
O-ring and install case (16). and nut (2).
8. Install tube (15). Tighten tube bolts to 3.75 Kg.m 11. Install main relief valve assembly (1).
(27 ft. lbs. torque.
L8-2 Hoist Circuit Component Repair L08010

FIGURE 8-3. HOIST VALVE ASSEMBLY (Continued)

HOIST CYLINDER
Removal
The hoist cylinder weighs approximately 330 Kg.
(728 lbs.). Be certain lifting equipment is adequate
for handling the load.
FIGURE 8-4. LOWER MOUNTING

1. Install two spacers (one on each side), approx. 1. Cable & Bracket 3. Hose
mm (3.9 inches) thick, between the contact sur- 2. Retainer 4. Hose
face of the frame and body (Figure 8-6). This will
allow enough clearance to retract and remove th
hoist cylinder.
2. Disconnect positioner cable and bracket (1, Figur
8-4).
NOTE: The positioner is on the left side only.
3. Remove mounting pin (2, Figure 8-5).
4. Fit a nylon rope around the hoist cylinder assem-
bly, then sling using a forklift truck as shown in
Figure 8-6.
5. Relieve hydraulic pressure by moving the hoist
control lever through all positions.
6. Disconnect hoses (3 & 4, Figure 8-4). Cap all hoses
and cylinder ports.
FIGURE 8-5. UPPER MOUNTING
7. Remove retainer (2).
1. Hoist Cylinder 2. Mounting Pin
8. Remove hoist cylinder assembly (1, Figure 8-5).

Installation
1. Position hoist cylinder on frame and body using a
forklift as shown in Figure 8-6.
2. Install mounting pin (2, Figure 8-5).
3. Install retainer (2, Figure 8-4) and tighten cap-
screws to standard torque.
4. Remove caps from hoses and cylinder ports.
Install hoses (3 & 4).
5. Connect positioner cable and bracket (1).
6. Refill hydraulic tank with engine oil (EO10-CD) to
the specified level, start the engine, and raise and
lower the body 2 - 3 times to circulate the oil FIGURE 8-6. HOIST CYLINDER
through the system. Then check the oil level REMOVAL/INSTALLATION
again. (Refer to hydraulic tank filling instructions,
this Section.)

Tools needed for rebuilding hoist cylinders: 1. Using a push tool, press fit bushing (3, Figure 8-8).
a. 790-502-1003 cylinder repair stand 2. Fit rod packing (2) and dust seal (4), and install
790-502-2000 cylinder repair stand snap ring (5).
b. 790-720-1000 ring expander 3. Using ring expander, fit piston ring (6, Figure 8-9)
NOTE: If a rebuild stand is not available, place cylinder to piston, and install wear ring (7).
on a suitable work bench. Be careful not to nick the 4. Assemble piston assembly (11), and install snap
cylinder rod. ring (10).
5. Install wear ring (8).
1. Remove mounting bolts (1, Figure 8-9) of cylinder 6. Using push tool, press fit bushing (6, Figure 8-7)
head assembly (2). to cylinder head.
2. Remove cylinder and rod assembly (3) from cylin- 7. Install rod packing (4), dust seal (5) and backup
der (5). ring (3), and O-ring (2) to cylinder head (1).
3. Remove piston mounting nut (9), then lift off rod 8. Assemble cylinder head assembly (11, Figure 8-9)
(3) from cylinder (5). to cylinder (5).
4. Remove cylinder head assembly (2). 9. Raise rod (3), align the stud bolt hole, and assem-
5. Remove dust seal (5, Figure 8-7), rod packing (4) ble in cylinder (5).
and bushing (6), O-ring (2), and backup ring (3) 10. Tighten piston mounting nut (9) to 33 ± 3.3 Kg.m
from cylinder head assembly. (239 ± 24 ft. lbs. torque.
6. Remove wear ring (8, Figure 8-9). 11. Assemble cylinder and rod assembly (4) to cylinder
7. Remove snap ring (10), and pull out piston assem- (5).
bly (11). 12. Install cylinder head assembly (2) with mounting
8. Remove piston ring (6) and wear ring (7) from bolts (1). Tighten bolts to 54 ± 8.0 Kg.m (391 ± 58
piston assembly. ft. lbs. torque.
9. Remove snap ring (5, Figure 8-8) from cylinder (1),

then remove dust seal (4), rod packing (2) and
bushing (3).
FIGURE 8-7. CYLINDER HEAD ASSEMBLY FIGURE 8-8. CYLINDER ASSEMBLY

1. Cylinder Head 4. Rod Packing 1. Cylinder 4. Dust Seal
2. O-Ring 5. Dust Seal 2. Rod Packing 5. Snap Ring
3. Backup Ring 6. Bushing 3. Bushing

FIGURE 8-9. HOIST CYLINDER ASSEMBLY
1. Bolt
2. Cylinder Head Assembly
3. Cylinder
4. Cylinder
5. Cylinder
6. Piston Ring
7. Wear Ring
8. Wear Ring
9. Piston Mounting Nut
10. Snap Ring
11. Piston Assembly
12. O-Ring
13. Backup Ring
14. Bushing
15. Rod Packing
16. Dust Seal
17. Snap Ring
18. Dust Seal
19. Rod Packing

NOTES

HYDRAULIC CHECKOUT
DUMP BODY CONTROL
The hoist control lever and hoist control valve ar This control system is equipped with a hoist limit sys -
connected by a mechanical control system consisting tem, so when the body is rising, the hoist limit is
of a push-pull cable. actuated when the body reaches the position set for
the limiter.
FIGURE 10-1. DUMP BODY COMPONENT LOCATION
1. Rod 5. Body Positioner 9. Intermediate Rod

2. Cable (from Hoist Control) 6. Hoist Limit Plate 10. Intermediate Lever
3. Hoist Control Lever 7. Cable (for Body Positioner) 11. Linkage Adjustment
4. Hoist Valve 8. Hoist Cylinder
L10002 12/ HYDRAULIC CHECKOUT L10-1

ADJUSTING HOIST LEVER LINKAGE 7. After adjusting, release the lock plate on the con -
sole box, and check that the travel from HOLD to
RAISE is the specified value (D, Figure 10-2) when
1. Lock the control levers inside the cab in the HOLD the control lever is operated to RAISE.
position with the lock plate on the console box. Specified value D: 15 mm (0.59 in)
2. Install and connect the push-pull cable so that
there is no twisting or slack.
3. Set hoist valve lever (1, Figure 10-2) in the HOLD
position.
4. Connect push-pull cable (2) and hoist valve lever
(1), adjust standard dimension A, then tighten the
locknut.
Standard dimension A: 198.5 mm (7.8 in)
5. Adjust intermediate rod (1, Figure 10-3) to stand-

ard dimension B.
Standard dimension B: 509 mm (20.04 in)
6. Connect push-pull cable (2, Figure 10-4) to inter-

mediate lever (1), adjust to standard dimension C,
then tighten the locknut.
Standard dimension C: 203.5 mm (8.01 in)
FIGURE 10-3. INTERMEDIATE ROD ADJUSTMEN
1. Intermediate Rod B. 509 mm (20.04 in)
2. Bellcrank
Hydrauli
Tank
FIGURE 10-2. HOIST VALVE ADJUSTMEN FIGURE 10-4. INTERMEDIATE LEVER ADJUSTMEN
1. Hoist Valve Lever A. 198.5 mm (7.8 in) 1. Intermediate Lever C. 203.5 (8.01 in)
2. Cable D. 15 mm (0.59 in) 2. Cable
L10-2 HYDRAULIC CHECKOUT L10002 12/

ADJUSTING HOIST LIMITER
1. Adjust push cable (1, Figure 10-5) to the standard

length A.
Standard length A: 180.25 mm (7.09 in)
2. With the dump body raised to a point 50 mm (1.

in) before the end of the hoist cylinder stroke,
adjust plate (2, Figure 10-6) so that the hoist valv
lever is released from the detent. FIGURE 10-5. LINKAGE ADJUSTMENT
Reference dimension B: 147 mm (5.79 in) 1. Cable A: 180.25 mm (7.09 in)
2. Linkage
FIGURE 10-6. HOIST LIMIT PLATE
1. Adjusting Nuts B: 147 mm (5.79 in)

2. Plate
3. Attaching Nut
4. Capscre

TESTING AND ADJUSTING HYDRAULIC
PRESSURE IN STEERING, HOIST
CIRCUIT
STEERING CIRCUIT
Stop the machine on level ground, apply the park-

ing brake, and put blocks under the tires.
Lower the body to the frame, stop the engine, then
remove the cap from the hydraulic tank and release th
pressure inside the cylinder circuit.
FIGURE 10-7. HYDRAULIC COMPONENT LOCATION
Measuring hydraulic pressure in steering circuit
1. Hoist Pressure Port 4. Check Valve Assembly
2. From Hoist Pump 5. To Hoist Valve
3. Inlet From Steering Pump 6. Steering Pressure Port
1. Raise the hydraulic oil temperature to 45- °C
(113-131° F)
2. Remove plug (6, Figure 10-7) and install
2
kg.cm (or a 5000 psi) pressure gauge.
3. Operate the steering wheel fully to the left or right,
and measure the hydraulic pressure when th
circuit is relieved with engine at high idle.
2
4. Relief pressure should be 210 +15 kg.cm (2986
+ 210 psi)
Adjusting hydraulic pressure in steering circuit

If the steering pressure is not within the standard value,
adjust as follows with demand valve.
FIGURE 10-8. PRESSURE ADJUSTMENT
1. Loosen locknut (1, Figure 10-8) and turn adjust -
ment screw (2) to adjust. 1. Locknut 2. Adjusting Scre
NOTE: To increase pressure, turn clockwise.To de-
crease pressure, turn counterclockwise.One turn of
the adjustment screw adjusts by 28 kg.cm2 (398 psi).
2. After adjusting, hold the adjustment screw with a
screwdriver to prevent it from turning, then tighten
the locknut and install the cap.
3. Check again so that the hydraulic pressure is
within the specified value.
NOTE: The pressure of crossover relief valve (4, Figure
10-9) cannot be adjusted when it is installed on the
machine, so do not attempt to adjust the pressure. FIGURE 10-9. CROSSOVER RELIEF VALVE
1. Crossover Relief 3. From Steering Valve
2. To Cylinder 4. To Cylinder

Measuring Steering Valve Discharge Pressure
2
2. Measure in the same way as when measuring the
hydraulic pressure in the steering circuit.
Measuring Hydraulic Pressure In Steering

Cylinde
1. Remove pressure measurement plug (3) (when
turning the steering to the left) or pressure meas-
urement plug (4) (when turning the steering to th
2
right), and install a 400 kg.cm (or a 5000 psi) FIGURE 10-10. STEERING PRESSURES
pressure gauge.
1. Inline Filter (LS Line) 3. Left Steer Pressur
2. Measure in the same way as when measuring the 2. Steering Valve Discharge 4. Right Steer Pressur
hydraulic pressure in the steering circuit.
HOIST CIRCUIT
Measuring Hydraulic Pressure In Hoist Circuit

1. Raise the hydraulic oil temperature to 45- °C
(113-131° F)
2. Remove pressure measurement plug (1, Figur
2
10-7) and install a 400 kg.cm (or a 5000 psi)
pressure gauge.
3. Disconnect the body positioner cable.
4. Operate the hoist control lever, and move th
dump body to the maximum dump position to
relieve the circuit, then measure the hydraulic
pressure with the engine at full throttle.
2
5. The pressure should be200+15 kg.cm (2885 +
213 psi).
FIGURE 10-11. HOIST RELIEF VALVE

1. Adjustment Screw 2. Locknut

Adjusting Hydraulic Pressure In Hoist Circuit
If the hydraulic pressure is not within the standard
value, adjust as follows.
Hoist cylinder pressure (adjust at hoist valve)
1. Loosen locknut (2, Figure 10-11) and turn adjust -
ment screw (1) to adjust.
NOTE: To increase pressure, turn clockwise. To de-
crease pressure, turn counterclockwise. One turn of
the adjustment screw adjusts by 52.9 kg.cm2 (752 psi).
2. After adjusting, hold the adjustment screw with a
screwdriver to prevent it from turning, then tighten
the locknut and install the cap.
3. Check again so that the hydraulic pressure is
within the specified value.
FIGURE 10-12. HOIST CYLINDER PRESSURE

Measuring Hoist Cylinder Pressure
1. Power Up Port 2. Return Line
2
2. Measure in the same way as when measuring the
hydraulic pressure in the hoist circuit.

HOIST CYLINDER LACKS LIFTING FORCE (LIFTING SPEED

HOIST CYLINDER DOES NOT MOVE

EXCESSIVE HYDRAULIC DRIFT OF DUMP BODY

STEERING FEEL IS HEAV

STEERING DOES NOT FUNCTIO

STEERING WHEEL VIBRATES
Cause Remedy
Air in hydraulic oil AC
Oil leakage in steering cylinder X

SECTION M
OPTIONS AND SPECIAL TOOLS
INDEX
QUICK FUEL SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M5-1
SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M8-1
AIR CONDITIONING SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-1
PAYLOAD METER II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-1
M01036 Index M1-1

NOTES
M1-2 Index M01036

WIGGINS QUICK FILL FUEL SYSTEM
FUEL TANK BREATHER VALVE
Removal
Unscrew breather valve (2, Figure 5-2) from tank (1).
Installation
Screw breather valve (2, Figure 5-2) into tank (1).
Disassembly
1. Remove spring clamp (4, Figure 5-1) from outlet.
2. Pull off rubber cover and screen (3).
3. Unscrew nut (5) from top of breather valve. Re-
move cover (6), spring (7), and steel ball (8).
4. Slide valve assembly (9) from housing.
5. Disengage tapered spring (1) containing three
balls (2) from valve stem.
Assembly
1. Clean and inspect all parts. If valve, body, or
springs are damaged, replace complete breather
valve.
2. Install in order; tapered spring, one steel ball, one
cork ball and one hollow aluminum ball.
3. Engage three coils of spring on small end of valve
stem with hollow aluminum ball.
4. Install valve into housing.
5. Place steel ball (8) on top of valve. Install spring
(7).
6. Place cover (6) over spring. Screw on large nut (5).
7. Install screen and rubber cover (3) over outlet.
8. Install spring clamp (4).
FUEL RECEIVER
The fuel receiver (3, Figure 5-2) is normally mounted
on the fuel tank (1). Optional locations are the left hand FIGURE 5-1. BREATHER VALVE
frame rail or at the Service Center. 1. Tapered Spring 6. Cover
Keep the cap on the receiver to prevent dirt build up in 2. Float Balls 7. Spring
valve area and nozzle grooves. If fuel spills from tank 3. Cover and Screen 8. Steel Ball
breather valve or tank does not completely fill, check 4. Spring Clamp 9. Valve Assembly
breather valve to see that float balls are in place and 5. Nut
outlet screen is clean. If valve is operating properly, the
problem will be with the fuel supply system.
M05004 4/90 Wiggins Quick Fill Fuel System M5-1

FIGURE 5-2. TYPICAL FUEL TANK BREATHER & RECEIVER INST.
1. Fuel Tank 3. Fuel Level Gauge
2. Breather Valve 4. Fuel Receiver
NOTE: This Illustration Represents a Typical Installation.

Fuel tank may vary in size, shape and location depending on truck model .
M5-2 Wiggins Quick Fill Fuel System M05004 4/90

SPECIAL TOOLS
SECTION C
PART
DESCRIPTION USE
NUMBER
Transmission
790-501-2000 Repair Stand
and Engine
SECTION C
PART
DESCRIPTION USE
NUMBER
799-203-8000 Tachometer Engine Speed
6215-81-3500 Adapter Engine Speed
SECTION D
PART
DESCRIPTION USE
NUMBER
Electrical
799-601-7400 T-Adapter Kit
Troubleshooting
Electrical
799-601-7200 Harness
Troubleshooting
Electrical
799-601-7300 Harness
Troubleshooting
M08009 11/ Special Tools M8-1

SECTION F
PART
DESCRIPTION USE
NUMBER
Plate Torque
790-901-5110
(Repair Stand) Converter
SECTION F
PART SERIAL RANGE RANGE
DESCRIPTION USE
NUMBER
799-605-1001 Shift Checker Transmission
799-607-1101 Modulation Checker Transmission
799-607-2000 Shift Checker Transmission BFP41-A & UP, BFP42-A & UP
799-607-2120 Harness Connector use with 799-607-2000 only BFP42-A & UP
799-607-3000 Shift Checker Transmission BFP42-A & UP, (Unit A10190 & UP

trucks serial number A10190 or higher, harness con-
nector 799-607-2120 must be used. Or, use shift NOTE: The Shift Checker and the Modulation Checker
checker 799-607-3000 and connect directly to trucks can only be used together as a unit.
M8-2 Special Tools M08009 11/

SECTION G
PART
DESCRIPTION USE
NUMBER
Drive Shaft
792-104-4501 Push Tool
Installation
SECTION G
PART
DESCRIPTION USE
NUMBER
792-520-2110 Small Installer Floating Seals

791-585-1510 Large Installer in Final Drive
792-520-2110 Small Push Tool Use With

791-585-1510 Large Push Tool Installers Abov
SECTION G
PART
DESCRIPTION USE
NUMBER
Differential
792-525-3000 Micrometer
Preload
SECTION G
PART
DESCRIPTION USE
NUMBER
Differential
790-425-1660 Wrench
Preload

SECTION G
PART
DESCRIPTION USE
NUMBER
Differential
790-425-1670 Adapters
Preload
SECTION G
PART
DESCRIPTION USE
NUMBER
792-530-1600 Large Seals

Push Tools
792-530-1700 Small Seals
1. Plate 5. Plate
2. Arm 6. Capscre
3. Stud 7. Wing Nut
4. Plate 8. Washer
SECTION G
PART
DESCRIPTION USE
NUMBER
Spanner Ring Nut On

09003-07280
Wrench Pinion Bearing

SECTION H
PART
DESCRIPTION USE
NUMBER
Removal of
790-450-1120 Plates
Rod Assembly
SECTION H
PART
DESCRIPTION USE
NUMBER
792-610-1000 Contains 2 Kits below
792-610-1100 Nitrogen Kit Adding Nitrogen
792-610-1200 Oil Charging kit Adding Oil
SECTION J
PART
DESCRIPTION USE
NUMBER
Fixture Final Drive &

790-438-1150
(3 Required) Brake Assembly
SECTION L
PART
DESCRIPTION USE
NUMBER
790-452-1100 Seal Installer Set

Steering Valve
790-452-1110 Seal Protector
Oil Seal
790-452-1120 Seal Installer
Installation
790-452-1130 Compression 1. Seal Protector 3. Seal Compression
Ring 2. Seal Installer Ring

SECTION L
REPAIR HYDRAULIC CYLINDERS
PART
ITEM DESCRIPTION
NUMBER
Wrench
1 790-102-3791
Assembly
2 790-102-3811 Wrench
3 790-102-3840 Tooth
4 790-102-3850 Tooth
5 790-102-3830 Tooth
6 01010-31260 Capscrew
7 01580-01210 Nut
8 01643-31232 Washer
9 790-102-3980 Bar
10 790-102-3151 Frame
11 790-102-33140 Frame
12 01010-31650 Capscrew
13 01580-01613 Nut
14 01643-31645 Washer
15 01010-31245 Capscrew
16 01580-01245 Nut

SECTION L
PART
DESCRIPTION USE
NUMBER
Steering Valve
790-452-1200 Pilot Ring Tool
Installation
1. Ring 4. Knob
2. Shaft 5. Spring Pin
3. Collar 6. Spring Pin
SECTION L
PART
DESCRIPTION USE
NUMBER
790-502-1003 or Hydrauli
Rebuild Stand
790-502-2000 Cylinder
790-102-3802 or Wrench
Gland Nut
790-102-3791 Assembly
1. Hydraulic Cylinder 3. Rebuild Stand
2. Cylinder Head 4. Wrench Assembly
SECTION L
PART
DESCRIPTION USE
NUMBER
790-302-1340 40 mm Socket Rod Nut
1. Cylinder Rod 3. 40 mm Socket

2. Rebuild Stand 4. Nut

SECTION L
PART
DESCRIPTION USE
NUMBER
Hyd. Cylinders
Piston Ring
790-720-1000 (Hoist &
Expander
Steering)
1. Expander 3. Clamp
2. Ring (rubber band)
SECTION L
PART
DESCRIPTION USE
NUMBER
799-101-5001 Hydraulic Tester Check Pressures
Digita
790-261-1102 Check Pressures
Hydraulic Tester

AIR CONDITIONING SYSTEM
Environmental Impact
Environmental studies have indicated a weakening of the earth’s protective Ozone (O3) layer in the outer strato-
sphere. Chloro-flouro-carbon compounds (CFC’s), such as R-12 refrigerant (Freon ® ), commonly used in mobil
equipment air conditioning systems, has been identified as a possible contributing fact or to the Ozone depletion.
Consequently, legislative bodies in more than 130 countries have mandated that the product ion and distribution of
R-12 refrigerant be discontinued after 1995. Therefore, a more “environmentally-friendly ” hydro-flouro-carbon
FIGURE 9-1. BASIC AIR CONDITIONING SYSTEM (TYPICAL)

1. Blower Switch 6. Temperature Sensor 10. Test gauges & Manifold 14. Compressor Drive Pulley
2. Thermostatic Switch 7. Evaporator 11. Compressor 15. Receiver/Dryer
3. Battery Supply 8. Expansion Valve 12. Refrigerant Container 16. Discharge Line
4. Circuit breake 9. Suction Line 13. Magnetic Clutch 17. Condenser
5. Blower
M09010 6/ Air Conditioning Syste M9-1

for HFC 134a Refrigerant
(HFC) refrigerant, commonly identified as HFC-134a, is being used in most current mobile air conditioning sys-
tems. Additionally, the practice of releasing either refrigerant to the atmosphere during the charging/recharging pro-
cedure is now prohibited.
These new restrictions require the use of new equipment and new procedures which are signific antly different from
those traditionally used in air conditioning service techniques. The use of new equipment a nd techniques allows for
complete recovery of refrigerants, which will not only help to protect the environment, but through the “re-cycling
of the refrigerant will preserve the physical supply, and help to reduce the cost of the refrigerant.
OPERATOR CAB AIR CONDITIONING PRINCIPLES OF REFRIGERATION

Mining and construction vehicles have unique charac- A brief review of the principles of air conditioning is
teristics of vibration, shock-loading, operator changes, necessary to relate the function of the components, th
and climate conditions that present different design technique of trouble shooting and the corrective action
and installation problems for Air Conditioning systems. necessary to put the A/C unit into top operating effi-
Off-highway equipment, in general, is unique enough ciency.
that normal automotive or highway truck engineering
Too frequently, the operator and the serviceman over-
is not sufficient to provide the reliability to endure th
look the primary fact that no A/C system will function
various work cycles encountered.
properly unless it is operated within a completely con-
The cab tightness, insulation, and isolation from heat trolled cab environment. The circulation of air must b
sources is very important to the efficiency of the sys- a directed flow. The cab must be sealed against seep-
tem. It is advisable to close all vents, even the intakes age of ambient air. The cab interior must be maintained
of pressurization systems, when there are high humid- for cleanliness, dust, and dirt which, if picked up in th
ity conditions. air system, will clog the intake side of the evaporator
coil.
The general cleanliness of the system and components
is important. Dust or dirt collected in the condenser,
AIR CONDITIONING
evaporator, or air filters decreases the system’s cooling
capacity. Air conditioning is a form of environmental control. As
applied to the cab, it refers to the control of temper -
The compressor, condenser, evaporator units, hoses
ture, humidity, cleanliness, and circulation of air. In th
and fittings must be installed clean and tight and be
broad sense, a heating unit is as much an air condi -
capable of withstanding the strain and abuse they are
tioner as is a cooling unit. The term “Air Conditioner
subjected to on off-highway vehicles.
is commonly used to identify an air cooling unit. To b
Equipment downtime costs are high enough to encour- consistent with common usage, the term “Air Condi-
age service areas to perform preventative maintenanc tioner” will refer to the cooling unit utilizing the princi-
at regular intervals on vehicle air-conditioning systems. ples of refrigeration; sometimes referred to as the
(Cleaning, checking belt tightness, and operation of evaporator unit.
electrical components).
M9-2 Air Conditioning Syste M09010 6/

REFRIGERATION - THE REFRIGERATION CYCLE
THE ACT OF COOLING In an air conditioning system, the refrigerant is circu -
• There is no process for producing cold; there is lated under pressure through the five major compo-
only heat removal. nents in a closed circuit. At these points in the system,
the refrigerant undergoes predetermined pressure and
• Heat is always drawn toward cold objects. This temperature changes.
principle is the basis for the operation of a cooling
unit. As long as one object has a temperatur The compressor (refrigerant pump) takes in low pres-
lower than another, this heat transfer will occur. sure heat laden refrigerant gas through the suction
valve (low side), and as its name indicates, pressurizes
• Temperature is the measurement of the intensity the heat laden refrigerant and forces it through the
of heat in degrees. The most common measuring discharge valve (high side) on to the condenser.
device is the thermometer.
Ambient air, passing through the condenser removes
• All objects have a point at which they will turn to the heat from the circulating refrigerant resulting in the
vapor. Water boiling is the most common exam- conversion of the refrigerant from gas to liquid.
ple of heating until vapor is formed. Boiling is
rapid form of evaporation. Steam is a great deal The liquid refrigerant moves on to the filter-receiver
hotter than boiling water. The water will not in - drier where impurities are filtered out, and moisture
crease in temperature once brought to a boil. Th removed. This component also serves as the tempo -
heat energy is used in the vaporization process. rary storage unit for the liquid refrigerant.
The boiling point of a liquid is directly affected by The liquid refrigerant, still under high pressure, then
pressure. By changing pressure, we can control flows to the expansion valve. This valve meters th
the boiling point and temperature at which amount of refrigerant entering the evaporator. As th
vapor will condense. When a liquid is heated and refrigerant passes through the valve, it becomes a low
vaporizes, the gas will absorb heat withou temperature, low pressure liquid and saturated vapor.
changing pressure. This gas is in a superheated
condition. The remaining low pressure liquid immediately starts
to boil and vaporize as it approaches the evaporator.
• Reversing the process, when heat is removed This causes the refrigerant to become cold. The hot,
from water vapor, it will return to the liquid state. humid air of the cab is pulled through the evaporator
Heat from air is attracted to a cooler object. by the evaporator blower. Since the refrigerant is
Usually the moisture in the cooled air will con- colder than the air, it absorbs the heat from the air
dense on the cooler object. producing cool air which is pushed back into the cab.
• Refrigerant - Only R-134a should be used in th The moisture in the air condenses upon movement into
new mobile systems which are designed for this the evaporator and drops into the drain pan from which
refrigerant. it drains out of the cab.
The cycle is completed when the heated low pressur
gas is again drawn into the compressor through th
suction side
This simplified explanation of the principles of refriger -
tion does not call attention to the fine points of refrig -
eration technology. Some of these will be covered in
the following discussions of the components, controls,
and techniques involved in preparing the unit for effi-
cient operation.

AIR CONDITIONER SYSTEM Condensing of the refrigerant is the change of state of
COMPONENTS the refrigerant from a vapor to a liquid. The action is
affected by the pressure of the refrigerant in the coil
COMPRESSOR (Refrigerant Pump) and air flow through the condenser. Condensing pres-
sure in an A/C system is the controlled pressure of th
The compressor separates the low pressure and th refrigerant which affects the temperature at which it
high pressure sides of the system. It concentrates th condenses to liquid, giving off large quantities of heat
refrigerant returning from the evaporator (low side) in the process.The condensing point is sufficiently high
creating a temperature much higher than the outside to create a wide temperature differential between the
air temperature. The high temperature differential be - hot refrigerant vapor and the air passing over th
tween the refrigerant and the outside air is necessary condenser fins and tubes. This difference permits rapid
to aid rapid heat flow in the condenser from the hot heat transfer from the refrigerant to ambient air.
refrigerant gas to much cooler outside air.
To create high pressure concentration, the compres-
sor draws in refrigerant from the evaporator through RECEIVER-DRIER
the suction valve and during compression strokes,
forces it out through the discharge valve to the con - The receiver-drier is an important part of the air condi-
denser. The pressure from the compressor action tioning system. The drier receives the liquid refrigerant
moves the refrigerant through the condenser, receiver- from the condenser and removes any moisture and
drier and connecting hoses to the expansion valve. foreign matter present which may have entered th
system. The receiver section of the tank is designed to
The compressor is driven by the engine through store extra refrigerant until it is needed by the evapo -
v-belt driving an electrically operated clutch mounted rator. The storage of this refrigerant is temporary and
on the compressor drive shaft. is dependent on the demand of the expansion valve.
A desiccant is a solid substance capable of removing
moisture from gas, liquid or solid. It is held in plac
SERVICE VALVES within the receiver between two screens, which also
Quick-connect hose end fittings with integral service act as strainers. Sometimes it is simply placed in a
valves attach to system service ports for servicing th metal mesh or wool felt bag. Filtering is accomplished
unit. A manifold gauge set is connected into the system by a separate strainer screen on the pickup tube
at the service valve ports and all procedures, such as Some sytems may utilize an accumulator instead of
discharging, evacuating and charging the system, are receiver-drier. If an accumulator is used, an expansion
performed through the service valves. (fixed-orifice) tube is used instead of the thermostatic
expansion valve described below. When used, th
expansion tube is located inside the inlet tube of th
CONDENSER evaporator and is used to restrict, but still allow
continuous flow of refrigerant to the evaporator coil.
The condenser receives the high pressure, high-tem-
perature refrigerant vapor from the compressor and
condenses it to high pressure, hot liquid.
THERMOSTATIC EXPANSION VALVE
It is designed to allow heat movement from the hot
refrigerant vapor to the cooler outside air. The cooling The thermostatic expansion valve controls the amount
of the refrigerant changes the vapor to liquid. Heat of refrigerant entering the evaporator coil. Both inter-
exchange is accomplished using cooler air flowing nally and externally equalized valves are used.
through the condenser. Condenser cooling can be with The expansion valve is located near the inlet of the
ram air provided by vehicle movement and sometimes evaporator and provides the functions of throttling,
aided by electric or hydraulic fans or by using the air modulating, and controlling the liquid refrigerant to th
movement provided by the radiator fan. evaporator coil.
Ram air condensers depend upon the vehicle mov - The refrigerant flows through a restriction creating a
ment to force a large volume of air past the fins and pressure drop across the valve. Since the expansion
tubes of the condenser. The condenser is usually lo - valve also separates the high side of the system from
cated in front of the radiator or on the roof of the truck. the low side, the state of the refrigerant entering the

valve is warm to hot high pressure liquid; exiting it is All or most of the liquid that did not change to vapor in
low pressure liquid and gas. The change to low pres- the expansion valve or connecting tubes boils (ex -
sure allows the flowing refrigerant to immediately begin pands) and vaporizes immediately in the evaporator,
changing to gas as it moves toward the evaporator. becoming very cold. As the process of heat loss from
the air to the evaporator coil surface is taking place,
The amount of refrigerant metered into the evaporator
any moisture (humidity) in the air condenses on the
varies with different heat loads. The valve modulates
cool outside surface of the evaporator coil and is
from wide open to the nearly closed position, seeking
drained off as water.
a point between for proper metering of the refrigerant.
At atmospheric pressure, refrigerant boils at a point
As the load increases, the valve responds by opening
lower than water freezes. Therefore, the temperature in
wider to allow more refrigerant to pass into the evapo-
the evaporator must be controlled so that the water
rator. As the load decreases, the valve reacts and
collecting on the coil surface does not freeze on and
allows less refrigerant into the evaporator. It is this
between the fins and restrict air flow. The evaporator
controlling action that provides the proper pressur
temperature is controlled through pressure inside th
and temperature control in the evaporator.
evaporator, and temperature and pressure at the outlet
The externally equalized expansion valve is controlled of the evaporator.
by both the temperature of the power element bulb and
the pressure of the liquid in the evaporator.
Some systems may use an internally equalized, block
type expansion valve. With this type valve, the refriger -
ant leaving the evaporator coil is also directed back
through the valve so the temperature of the refrigerant
is monitored internally rather than by a remote sensing
bulb.
NOTE: It is important that the sensing bulb, if present,
is tight against the output line and protected from
ambient temperatures with insulation tape.
EVAPORATOR
The evaporator cools and dehumidifies the air befor
it enters the cab. Cooling a large area requires that
large volumes of air be passed through the evaporator
coil for heat exchange. Therefore, a blower becomes
a vital part of the evaporator assembly. It not only draws
heat laden air into the evaporator, but also forces this
air over the evaporator fins and coils where the heat is
surrendered to the refrigerant. The blower forces th
cooled air out of the evaporator into the cab.
Heat exchange, as explained under condenser oper -
tion, depends upon a temperature differential of the air
and the refrigerant. The greater the temperature differ-
ential, the greater will be the amount of heat exchanged
between the air and the refrigerant. A high heat load
condition, as is generally encountered when the air
conditioning system is turned on, will allow rapid heat
transfer between the air and the cooler refrigerant.
The change of state of the refrigerant in and going
through the evaporator coil is as important as that of
the air flow over the coil.

ELECTRICAL CIRCUIT COMPRESSOR CLUTCH
The air conditioner’s electrical circuit is fed from an An electromagnetic clutch is used in conjunction with
accessory circuit and is fused with a 30-ampere fus the thermostat to disengage the compressor when it is
or circuit breaker. not needed, such as when a defrost cycle is indicated
in the evaporator, or when the system is turned off.
The blower control is a switch which provides a rang
of blower speeds from fast to slow. When the blower The stationary field clutch is the most desirable type
switch is turned on, current is fed to the thermostat. since it has fewer parts to wear out. The field is mounted
Once the blower is turned on, fan speeds may b to the compressor by mechanical means depending
changed without affecting the thermostat sensin on the type field and compressor. The rotor is held on
level. the armature by a bearing and snap rings. The arm -
ture is mounted on the compressor crankshaft.
The thermostat reacts to changing temperatures which
cause electrical contacts to open and close. Th When no current is fed to the field, there is no magnetic
thermostat has a capillary tube extended into th force applied to the clutch and the rotor is free to rotat
evaporator coil to sense temperature. on the armature, which remains stationary on th
crankshaft.
When the contacts are closed, current flows to th
clutch field and energizes the clutch, causing the When the thermostat or switch is closed, current is fed
crankshaft to turn which starts the refrigeration cycle. to the field. This sets up a magnetic force between the
When the temperature of the evaporator coil drops to field and armature, pulling it into the rotor. When th
a predetermined point, the contacts open and th armature becomes engaged with the rotor, the com -
clutch disengages. plete unit rotates while the field remains stationary.This
causes the compressor crankshaft to turn, starting th
When the clutch is disengaged, the blower remains at refrigeration cycle
the set speed. After the evaporator temperature rises
about twelve degrees above the cutout point, the con - When the switch or thermostat is opened, current is cut
tacts in the thermostat close and the refrigeration cycle off. The armature snaps back out and stops while th
resumes. rotor continues to turn. Pumping action of the com -
pressor is stopped until current is again applied to th
field. In addition, safety switches in the compressor
clutch electrical circuit control clutch operation, dise -
THERMOSTAT gaging the clutch if system pressures are abnormal.
An electromagnetic clutch is used on the compressor
to provide a means of constant temperature control of SAFETY SWITCHES
the cab. The clutch is controlled by a thermostat in th
evaporator which is set initially by the driver to a pr - Trinary Switch
determined point. Coil temperature is then maintained The Trinary switch performs three distinct functions
by the cycling action of the clutch. to monitor and control refrigerant pressure in the sys -
The thermostat is simply a thermal device which con - tem. This switch is installed between the condenser
trols an electrical switch. When warm, the switch is and expansion valve, usually on the receiver-drier. Th
closed; when cold, it is open. Most thermostats hav switch functions are:
positive OFF position as a means to turn the clutch OFF The low-pressure switch prevents compressor
regardless of temperature. operation if the refrigerant has been lost or the
The bellows type thermostat has a capillary tube con- ambient temperature is too low. Low ambient
nected to it which is filled with refrigerant. The capillary temperature results in very low system pressure.
tube is attached to the bellows inside of the thermostat. The mid-range function actuates the engine fan
Expansion of the gases inside the capillary tube exerts clutch if installed.
pressure on the bellows, which in turn closes the con-
tacts at a predetermined temperature. The high-range pressure function disengages
the compressor clutch if system pressure is too
high.
The switch functions will automatically reset when sys-
tem pressure returns to normal.

SYSTEM SERVICING Ensure sufficient ventilation whenever refrigerant
is being discharged from a system, keeping in
Servicing an air conditioning system really means mind refrigerant is heavier than air and will see
closely monitoring refrigerant flow. For this reason, low areas of shop.
the following procedures deal extensively with th
proper use, handling, care and safety factors involved When exposed to flames or sparks, the compo-
in the R-134a refrigerant quality and quantity in an air nents of refrigerant change and become deadl
conditioning system. phosgene gas. This poison gas will damage the
respiratory system if inhaled. NEVER smoke in area
Because the refrigerant in an air conditioning syste where refrigerant is used or stored.
must remain pressurized and sealed within the unit to
function properly, safety is a major consideration when Never direct steam cleaning hose or torch in direct
anything causes this pressurized, sealed condition to contact with components in the air conditioning
change. The following warnings are provided here to system. Localized heat can raise the pressure to a
alert service personnel to their importance BEFORE dangerous level.
learning the correct procedures.Read, remember, and Do not heat or store refrigerant containers above
observe each warning before beginning actual system 120° F (49° C).
servicing.
Do not flush or pressure test the system using shop
NOTE: If the mine operates a fleet with some trucks air or another compressed air source. Certain mix -
using R-12 and others using R-134a refrigerant, it is tures of air and R-134a refrigerant are combustible
essential that servicing tools that come into contact when slightly pressurized. Shop air supplies also
with the refrigerant (gauge sets, charging equipment, contain moisture and other contaminants that
recycle/recovery equipment etc.) be dedicated to one could damage system components.
type refrigerant only, to prevent cross contamination.
R-134a Refrigerant Containers

Federal regulations prohibit venting R-12 and Two basic, readily available containers are used to
R134a refrigerant into the atmosphere. An SAE and store R-134a: the 30 or 60 pound bulk canisters (Figur
UL approved recovery/recycle station must be 9-2).
used to remove refrigerant from the AC system.
Always read the container label to verify the contents
Refrigerant is stored in a container on the unit fo
are correct for the system being serviced. Note th
recycling, reclaiming, or transporting. In addition,
containers for R-134a are painted light blue.
technicians servicing AC sytems must be certified
they have been properly trained to service the
system.
Although accidental release of refrigerant is a re -
mote possibility when proper procedures are fol-
lowed, the following warnings must be observed
when servicing AC systems:
Provide appropriate protection for your eyes (gog-
gles or face shield) when working around refrige -
ant.
A drop of the liquid refrigerant on your skin will
produce frostbite. Wear gloves and exercise e -
treme care when handling refrigerant.
If even the slightest trace of refrigerant enters in
FIGURE 9-2. R-134a CONTAINERS
your eye, flood the eye immediately with cool wate
and seek medical attention as soon as possible. 1. 30 Pound Cylinder 2. 60 Pound Cylinder

SERVICE TOOLS AND EQUIPMENT
RECOVERY/RECYCLE STATION
Mixing different types of refrigerant will damage
Whenever refrigerant must be removed from the sys-
equipment. Dedicate one recovery/recycle station
tem, a dual purpose station as shown in Figure 9-7,
to each type of refrigerant processing to avoid
performs both recovery and recycle procedures which
equipment damage.
follows the new guidelines for handling used refriger -
DISPOSAL of the gas removed requires laboratory
ant. The recovered refrigerant can then be recycled to
or manufacturing facilities.
reduce contaminants, and reused in the same machine
or fleet. Test equipment is available to confirm the refrigerant
in the system is actually the type intended for th
NOTE: To be re-sold, the gas must be “re-claimed”
system and has not been contaminated by a mixtur
which leaves it as pure as new, but requires equipment
of refrigerant types.
normally too expensive for all but the largest refriger -
tion shops. Recycle equipment must meet certain standards as
published by the Society of Automotive Engineers and
Equipment is also available to just remove or extract
carry a UL approved label. The basic principals of
the refrigerant. Extraction equipment does not clean
operation remain the same for all machines, even if th
the refrigerant - it is used to recover the refrigerant from
details of operation differ somewhat.
an AC system prior to servicing.
To accomplish this, the recovery/recycle station sep - LEAK DETECTOR
rates the oil from the refrigerant and filters the refriger -
The electronic detector (Figure 9-4) is very accurat
ant multiple times to reduce moisture, acidity, and
and safe. It is a small hand-held device with a flexibl
particulate matter found in a used refrigerant.
probe used to seek refrigerant leaks. A buzzer, alarm
or light will announce the presence of even the smallest
leak.
Note that electronic leak detectors are available for
use only with R-12 or only with R-134a, while other
models are suitable for use with either.
FIGURE 9-3. RECOVERY/RECYCLE STATION

FIGURE 9-4. TYPICAL ELECTRONIC LEAK
DETECTOR

FIGURE 9-5. R-134a SERVICE VALVE FIGURE 9-6. VACUUM PUMP
1. System Service Port 3. Service Hose
Fitting Connection
2. Quick Connect
SERVICE VALVES VACUUM PUMP

Because an air conditioning system is a sealed system, The vacuum pump (Figure 9-6) is used to completely
two service valves are provided on the compressor to evacuate all of the refrigerant, air, and moisture from
enable diagnostic tests, system charging or evacu - the system by deliberately lowering the pressure within
ation. Connecting the applicable hoses from the mani- the system to the point where water turns to a vapor
fold gauge set to the compressor service valves (boils) and together with all air and refrigerant is with -
enables each of these to be readily performed. drawn (pumped) from the system. Normally the vac-
uum pump is only used when a system has completely
New and unique service hose fittings (Figure 9-5) have
lost its refrigerant charge
been specified for R-134a systems. Their purpose is to
avoid accidental cross-mixing of refrigerants and lubri-
cants with R-12 based systems. The service ports on
the system are quick disconnect type with no external
threads. They do contain a Schrader type valve. Th
low side fitting has a smaller diameter than the high side
attachment.
Protective caps are provided for each service valve
When not being used these caps should be in place to
prevent contamination or damage to the service
valves.

MANIFOLD GAUGE SET
A typical manifold gauge set (Figure 9-7) has two scre
type hand valves to control access to the system, two
gauges and three hoses. The gauges are used to read
system pressure or vacuum. The manifold and hoses
are for access to the inside of an air conditioner, to
remove air and moisture, and to put in, or remove,
refrigerant from the system. Shutoff valves are required
within 12 inches of the hose end(s) to minimize refrig -
erant loss.
A gauge set for R-134a will have a blue hose with
black stripe for the low side, a red hose with a black
stripe for the high side, and a yellow hose with a black
stripe for the utility (center) hose. The hoses use a 1/
in. ACME female nut on the gauge end. Special quick
disconnect couplings are normally combined with
shutoff valve on the high and low side hoses. The fr
end of the center hose contains a 1/2 in. ACME femal FIGURE 9-7. MANIFOLD GAUGE SET
nut and a shutoff device within 12 inches of the hos
end. These special hoses and fittings are designed to
minimize refrigerant loss and to preclude putting th Low Side Gauge
wrong refrigerant in a system. The Low Side Gauge, registers both vacuum and pres -
sure. The vacuum side of the scale is calibrated from
to 30 inches of mercury (in. Hg). The pressure side of
NOTE: When hose replacement becomes necessary, the scale is calibrated to 150 psi.
the new hoses must be marked “SAE J2916 R-134a”.
Functions of the manifold gauge set are included in

many of the commercially available recovery or recov-
ery/recycle stations. Never open the hand valve to the high side at
anytime when the air conditioning system is ope -
ating. High side pressure, if allowed, may rupture
charging containers and potentially cause pe -
sonal injury.
High Side Gauge

The High Side Gauge is used to measure pressure only
on the discharge side of the compressor. The scale is
calibrated from 0 to 500 psi.

INSTALLING MANIFOLD GAUGE SET
Before attempting to service the air conditioning sys-
tem, a visual inspection of both the engine and system
components is recommended. Particular attention
should be paid to the belts, hoses, tubing and all
attaching hardware plus the radiator cap, fan clutch,
and thermostat. Inspect both the condenser and th
radiator for any obstructions or potential contamina-
tion. Minimize all the possibilities for error or malfunc-
tion of components in the air conditioning system.
Shut off engine. DO NOT attempt to connect serv-

icing equipment when the engine is running.
1. Be sure all valves on the manifold are closed all

the way (turn them clockwise).
2. Check the hose connections on the manifold for
tightness.
3. Locate the low and high side system service FIGURE 9-8. SERVICE HOSE HOOK-UP
fittings and remove their protective caps.
4. Connect the two service hoses from the manifold
to the correct service valves on the compressor
as shown in Figure 9-8. (High side to compressor
discharge valve and low side to compressor suc-
tion side.) Do not open service valves at this time.
This gauge hook-up process will be the same, regard -

less of the gauge set being installed. Whether it is
recovery station or individual gauges, the connections
are the same. The procedures performed next will vary
depending what type of equipment is being used. If
recovery/recycling station is being used, complete
servicing can be accomplished. Using only a set of
gauges will limit the servicing to only adding refrigerant
or observing pressures.

Purging Air From Service Hose Adding Refrigerant to the System
(without a charging station
The purpose of this procedure is to remove all the air
trapped in the hoses prior to actual system testing. After determining that the system is low and requires
Environmental regulations require that all service additional refrigerant perform the following proc -
hoses have a shutoff valve within 12 inches of th dures.
service end. These valves are required to ensure only
1. Connect the center hose from the manifold gaug
a minimal amount of refrigerant is lost to the atmos-
set to the refrigerant dispensing valve on the con-
phere. R-134a gauge sets have a combination quick
tainer.
disconnect and shutoff valve on the high and low sides.
The center hose also requires a valve. 2. Start the engine and set the idle at 1200 to
RPM and then turn on the air conditioning.
The initial purging is best accomplished when con -
nected to recovery or recycle equipment. With the 3. Open the refrigerant dispensing valve on the con-
center hose connected to the recovery station, service tainer and then the low pressure hand valve on th
hoses connected to the high and low sides of th manifold. This will allow the refrigerant to enter th
system, we can begin the purging. The manifold valves system as a gas on the low pressure or suction
and service valves should be closed. Activating the side of the compressor. The compressor will pull
vacuum pump will now pull any air or moisture out of refrigerant into the system.
the center hose. This will require only a few minutes of
4. Continue adding refrigerant until the gauge reads
time. The hose is the only area that is being placed in
in the normal range. Gauge readings will fluctuat
a vacuum and this will not require a lengthy process.
as the compressor cycles on and off.
Closing the valve will then insure the hose is purged. It
is now safe to open the other manifold valves. Pressures within the air conditioning system vary
with ambient temperature. A normal pressure
range is defined as follows:
Low side 15 - 30 PSI
High side 170 - 300 PSI
FIGURE 9-9. PURGING SYSTEM

5. When the gauges show a normal reading, clos
the hand valve on the refrigerant container.
Do not open high side hand valve. High side -

Stabilizing the AC System tem pressure is greater than refrigerant container.
Serious personal injury may result if the containe
explodes.
Use hand valve to regulate low side reading during
charging. DO NOT EXCEED 40 psi maximum.
During this stabilization period, do not open hand Exceeding this pressure may cause compresso
valves on manifold for any reason. Equipment dam- failure.
age and personal injury may result.
1. Start the engine and return to an idle speed of

to 1500 RPM. Turn on the air conditioner. RECOVERING AND RECYCLING THE
REFRIGERANT
2. After a performance check of the control functions,
blower speeds and air flow, set the AC system Draining the Oil from the Previous Recovery Cycl
controls to maximum cooling and blower speed
1. Place the power switch and the controller on th
on high. All windows must be closed. If the cab
recovery unit in the OFF position.
temperature is hot, open the windows long
enough to allow the hot air to move out of the cab. 2. Plug in the recovery station to the correct power
source.
3. Run the engine and air conditioner about 5 minutes
for the system to stabilize. 3. Drain the recovered oil through the valve marked
OIL DRAIN on the front of the machine.
4. If the humidity is high it will be necessary to plac
a fan in front of the AC condenser to help the air 4. Place the controller knob in the ON position. Th
flow across the condenser. This helps to stabiliz low pressure gauge will show a rise.
the system by simulating normal operating condi-
5. Immediately switch to the OFF position and allow
tions
the pressure to stabilize. If the pressure does not
5. It is then possible to observe the gauge readings rise to between 5 psi and 10 psi, switch the con-
and the temperature coming out of the air ducts troller ON and OFF again.
with a thermometer.
6. When the pressure reaches 5 to 10 psi, open th
OIL DRAIN valve, collect oil in an appropriat
NOTE: If low refrigerant is indicated by lower than container, and dispose of container as indicated
normal pressure readings, add refrigerant to enable by local, state or Federal Regulation. THE OIL IS
adequate system testing. NOT REUSABLE, DUE TO CONTAMINANTS AB-
SORBED DURING ITS PREVIOUS USE.
Adding Refrigerant and Stabilizing the System
(with a recovery/recycling station Performing the Recovery Cycle
When using a recovery/recycling station the procedur 1. Be sure the equipment being used is designed for
is the same as previously described. The difference is the refrigerant you intend to recover.
that instead of just opening the refrigerant container
2. Observe the sight glass oil level. Having drained
the refrigerant should be added 0.5 to 1 pound at
it, it should be zero.
time. After each instance of adding the refrigerant,
pause long enough to observe the gauge reading to 3. Check the cylinder refrigerant level before begin -
determine if the system is full. Again using the pres- ning recovery to make sure you have enough
sures that were mentioned above. capacity.
4. Confirm that all shut-off valves are closed befor
connecting to the AC system.
5. Attach the appropriate hoses to the system being
recovered.

6. Start the recovery process by operating the equip- Evacuating the System
ment as per the manufacturer’s instructions.
1. Attach the high and low side hoses to the appro-
7. Continue extraction until a vacuum exists in the AC priate connections.
system.
2. Start the vacuum pump and run it for five minutes.
8. If an abnormal amount of time elapses after th
3. Check the gauge readings for five minutes. If th
system reaches 0 psi and does not drop steadily
gauge needle moves up, the system is not sealed.
into the vacuum range, close the manifold valves
The vacuum that was just created did not hold, air
and check the system pressure. If it rises to 0 psi
and moisture are being sucked into the system by
and stops, there is a major leak.
that same vacuum.
9. Check the system pressure after the recovery
4. Tighten any loose connections.Re-start the pump,
equipment stops. After five minutes, system pres -
and open the hand valves on the gauges again.
sure should not rise above “0” gauge pressure. If
Repeat the vacuum test.
the pressure continues to rise, restart and begin
the recovery sequence again. This cycle should 5. If the leak has been repaired, run the vacuum
continue until the system is void of refrigerant. pump for at least an hour to remove any moistur
from the system.
10. Check the sight glass oil level to determine th
amount of oil that needs to be replaced. (Th The moisture must turn to gas before the pump can pull
amount of oil that was lost during the recovery it out. The moisture takes time to boil away, so that it
cycle must be replaced back into the system). can be drawn out of the system. The vacuum pump can
draw most of the air out quickly, but a deep vacuum
11. Mark the cylinder with a RECOVERED (red) mag-
requires more time; the deeper the vacuum the mor
netic label to reduce the chance of charging a
time required.
system with contaminated refrigerant. Record the
amount of refrigerant recovered.
Charging the AC System

Performing the Recycling Procedure When adding a full charge of refrigerant, it is possibl
to put it in as a gas or as a liquid. Adding refrigerant as
The recovered refrigerant contained in the cylinder
a liquid is faster but can damage the compressor if not
must undergo the recycle procedure before it can b
done correctly. The procedure used, and where the
reused. The recycle or clean mode is a continuous loop
refrigerant is added in the AC system makes a differ-
design and cleans the refrigerant rapidly. Follow equip-
ence. When using refrigerant as a liquid, never add
ment manufacturer’s instructions for this procedure.
more than two thirds of system requirements as a
liquid. Finish charging the system using gas.
Evacuating and Charging the AC System

Evacuate the system once the air conditioner compo-
nents are repaired or replacement parts are secured,
and the AC system is reassembled. Evacuation re-
moves air and moisture from the system. Then, the AC
system is ready for the charging process, which adds
new refrigerant to the system.

SYSTEM PERFORMANCE TEST SYSTEM LEAK TESTING
This test is performed to establish the condition of all Refrigerant leaks are probably the most common
components in the system. Observe these conditions cause of air conditioning problems, resulting from im-
during testing: proper or no cooling, to major internal component
damage. Leaks most commonly develop in two or
1. Start engine and operate at 1200 to 1500 RPM.
three places. The first is around the compressor shaft
2. Place fan in front of condenser to simulate normal seal, often accompanied by an indication of fresh r -
ram air flow and allow system to stablize. frigerant oil. If a system is not operated for a whil
(winter months), the shaft seal may dry out and leak
3. Place a thermometer in air conditioning vent clos-
slightly. The centrifugal force of the clutch pulley spin -
est to evaporator.
ning can also cause the problem. When the system is
4. Evaluate the readings obtained from the gauges operated and lubricant wets the seal, the leak may stop.
to see if they match the readings for the ambient Such leaks can often be located visually, or by feeling
temperature. with your fingers around the shaft for traces of oil. (Th
R-134a itself is invisible, odorless, and leaves no trac
As preliminary steps to begin checkout of the system,
when it leaks, but has a great affinity for refrigerant oil.)
perform the following:
A second common place for leaks is the nylon and
1. Close all windows and doors to the cab.
rubber hoses where they are crimped or clamped to
2. Set air conditioning system at maximum cooling the fittings, or where routing allows abrasion. Other
and blower speed operation. threaded joints or areas where gaskets are used should
be visually and physically examined. Moving your fin -
3. Readings on the two manifold gauges should b
gers along the bottom of the condenser and evapor -
within normal range, adjust for ambient temper -
tor, particularly near the drain hole for the condensate
ture.
will quickly indicate the condition of the evaporator.
4. Compare evaporator discharge air temperature Any trace of fresh oil here is a clear indication of a leak.
reading to see if it matches the recommended
Usually, a 50% charged system is enough to find most
temperature for the ambient temperature and
leaks. If the system is empty, connect the manifold
gauge readings obtained.
gauge set to the system and charge at least one (1) lb.
5. Carefully feel the hoses and components on th of refrigerant into the system.
high side. All should be warm-hot to the touch.
Check the inlet and outlet of receiver-drier for even
temperatures, if outlet is cooler than inlet, a re -
striction is indicated.
Use extreme caution leak testing a system while
the engine is running.
In its natural state, refrigerant is a harmless, color-
less gas, but when combined with an open flame,
Use extreme caution when placing hands on high it will generate toxic fumes (phosgene gas), which
side components and hoses. Under certain condi - can cause serious injuries or death.
tions these items can be extremely hot.
NOTE: The refrigerant is heavier than air and will move
6. Feel the hoses and components on the low side. down when it leaks. Apply pickup hose or test probe
They should be cool to the touch. Check connec- on the undersurface of all components to locate leak.
tions near the expansion valve, inlet side should
be warm and cold-cool on the outlet side. Electronic leak detecto
7. If these conditions are met, the system is consid- (Refer to Figure 9-4). As the test probe is moved into
ered normal. Shut down engine. Remove gauges an area where traces of refrigerant are present, a visual
and install the caps on the service valves. or audible announcement indicates a leak. Audibl
units usually change tone or speed as intensity
changes.

Tracer dye SYSTEM REPAIR
Tracer dyes are available that can be added to th The following service and repair procedures are not
system as refrigerant is added. The system is then any different than typical vehicle service work. How-
operated to thoroughly circulate the dye. As refrigerant ever, AC system components are made of soft metals
escapes, it leaves a trace of the dye at the point of (copper, aluminum, brass, etc.). Comments and tips
leakage, which is then detected using an ultraviolet that follow will make the job easier and reduce unnec-
light (“black light”), revealing a bright fluorescent glow. essary component replacement.
Soap and wate

Soap and water can be mixed together and applied to
system components. Bubbles will appear to pinpoint
the specific location of leaks. All of the service procedures described are onl
performed after the system has been discharged.
After determining the location or source of leak(s),
Never use any lubricant or joint compound to
repair or replace leaking component(s).
lubricate or seal any AC connections.
NOTE: The length of the hose will affect the refrigerant
capacity. When replacing hoses, always use the same
NOTE: To help prevent air, moisture or debris from
hose length, if possible.
entering an open system, cap or plug open lines,
fittings or components and lubricant containers until
connected and as soon as they are disconnected.
Keep all connections clean (also caps and plugs
used) so debris can’t enter accidentally.
Before system assembly, check the compressor oil
level and fill to manufacturer specifications.
Hoses and Fitting
When replacing hoses, be sure to use the same type
and ID hose you removed. When hoses or fittings are
shielded or clamped to prevent vibration damage, b
sure these are in position or secured.
Lines
Always use two wrenches when disconnecting or con-
necting AC fittings attached to metal lines. You ar
working with copper and aluminum tubing which can
kink or break easily. Tube O-ring type fittings require
only 18 ft. lbs. (24.4 N.m of torque for correct sealing.
When grommets or clamps are used to prevent lin
vibration, be certain these are in place and secured.
Expansion Valve
When removing the expansion valve from the system,
remove the insulation, clean the area and disconnect
the line from the receiver-drier. Detach the capillary
(bulb) and external equalizer tube (if present) from their
mounting locations. Remove the expansion valve from
the evaporator inlet. Expansion valve service is limited
to cleaning or replacing the filter screen. If this is not
the problem, replace the valve. Secure the capillary
and equalizer, if used, to clean surfaces and replace or
attach any insulating material.

Receiver-Drie Sometimes it may be necessary to use shims or e -
large the slots in the compressor mounting bracket to
The receiver-drier can not be serviced or repaired. It
achieve proper alignment.
should be replaced whenever the system is opened for
any service. If the receiver-drier has a pressure switch Excessive clutch plate wear is caused by the plat
to control the clutch, it should be removed and installed rubbing on the clutch pulley when the clutch is not
on the new unit. engaged or the clutch plate slipping when the clutch
coil is energized. A gap that is too small or too larg
Thermostat between the plate and clutch pulley or a loss of clutch
plate spring temper are possible causes. The ideal air
A thermostat can be stuck open or closed due to
gap between the clutch pulley and the clutch plate is
contact point wear or fusion. The thermostat temper -
0.022 to 0.057 in. If the gap is too wide, the magnetic
ture sensing element (capillary tube) may be broken or
field created when the clutch coil is energized will not
kinked closed and therefore unable to sense evapor -
be strong enough to pull and lock the clutch plate to
tor temperature.
the clutch pulley.
When thermostat contact points are stuck open or th
sensing element can not sense temperature in th Compressor
evaporator, the clutch will not engage (no AC system
The compressor can fail due to shaft seal leaks (no
operation). Causes are a loss of charge in the capillary
refrigerant in the system), defective valve plates, bear-
tube or a kink, burned thermostat contact or just no
ings, other internal parts or problems associated with
contact. When troubleshooting, bypass the thermostat
high or low pressure, heat or lack of lubrication. Be sure
by hot wiring the clutch coil with a fused lead. If th
the compressor is securely mounted and the clutch
clutch engages, replace the thermostat.
pulley is properly aligned with the drive pulley.
Thermostat contact points may be fused (burned)
Use a mechanic’s stethoscope to listen for noises
closed and the clutch will not disengage. Causes ar
inside the compressor.
faulty switch that could be due to fatigue. The thermo -
stat must be replaced. When the clutch will not disen-
CHECKING COMPRESSOR OIL LEVEL
gage you may also note that condensate has frozen on
the evaporator fins and blocked air flow. There will also Every air conditioning system and compressor de-
be below normal pressure on the low side of th pends on refrigeration oil for lubrication and safe op -
system. Side effects can be compressor damage eration.
caused by oil accumulation (refrigeration oil tends to
Refrigerant oil is a synthetic oil very susceptible to high
accumulate at the coolest spot inside the system) and
levels of water absorbtion. Always be sure the oil is an
lower than normal suction pressure that can starve th
approved type for use in the air conditioner compres-
compressor of oil.
sor.
Clutch Refrigerant oil, under normal circumstances inside th
sealed system, cannot go anywhere, and there is no
Clutch problems include electrical failure in the clutch
need to check the oil at such times. Always keep a cap
coil or lead wire, clutch pulley bearing failure, worn or
on an oil container except when in use. Moisture is
warped clutch plate or loss of clutch plate spring tem-
quickly absorbed by the oil.
per. Defective clutch assembly parts may be replaced
or the whole assembly replaced. If the clutch shows Whenever a system is opened for service, the com-
obvious signs of excessive heat damage, replace th pressor oil level should be checked and clean refrig-
whole assembly. eration oil added as required by the manufacturer’s
specifications (usually located on compressor).
The fast way to check electrical failure in the lead wir
or clutch coil is to hot wire the coil with a fused lead.
This procedure enables you to bypass clutch circuit
control devices.
Clutch pulley bearing failure is indicated by bearing
noise when the AC system is off or the clutch is not
engaged. Premature bearing failure may be caused by
poor alignment of the clutch and clutch drive pulley.

EVACUATING THE SYSTEM
Evacuating the complete air conditioning system is
required in all new system installations, and when
repairs are made on systems requiring a component
replacement (system opened), or a major loss of refrig-
erant has occurred. All these conditions will require that
a vacuum be pulled using a vacuum pump that com-
pletely removes any moisture from the system. Onc
properly evacuated, the system can be recharged
again.
Using a pump to create a vacuum in the air condition-
ing system effectively vaporizes any moisture, allowing
the water vapor to be easily drawn out by the pump.
The pump does this by reducing the point at which
water boils (212°F at sea level with 14.7 psi). In
vacuum, water will boil at a lower temperature depend-
ing upon how much of a vacuum is created.
As an example, if the ambient air outside the truck is
75°F at sea level, by creating a vacuum in the system
so that the pressure is below that of the outside air (in
this case, at least 29.5 inches of vacuum is needed),
the boiling point of water will be lowered to 72°F. Thus
any moisture in the system will vaporize and be drawn
out by the pump if the pump is run for approximately
an hour. The following steps indicate the proper pro -
cedure for evacuating all moisture from the heavy duty FIGURE 9-10. VACUUM PUMP HOOKUP
air conditioning systems.
1. Low Pressure Hand Valv 3. Vacuum Pump
2. High Pressure Hand Valv
4. Observe gauge reading and wait 10 minutes.

Reading should not vary more than 1-2 in. hg.
Do not use the air conditioning compressor as
After waiting, if more vacuum is lost than this,
vacuum pump or the compressor will be damaged.
serious leak is indicated and the system must b
recharged, leak tested, repaired and evacuated.
NOTE: Lower the vacuum requirement one inch for
5. Turn on pump, open hand valves and continu
every 1000 feet above sea level at your location.
evacuation for at least one hour.
NOTE: If system has excessive amounts of moisture,
1. With the manifold gauge set still connected (after
60 minutes evacuation may not be sufficient since the
discharging the system), connect the center hos
water must turn to a vapor to be drawn out of the
to the inlet fitting of the vacuum pump as shown
system. If it has been verified that no system leaks exist
in Figure 9-10. Then open the low side hand valves
and gauge readings increase after 1 hour, extend the
to maximum.
evacuation time to ensure total moisture remova
2. Open the discharge valve on the vacuum pump or
remove the dust cap from the discharge outlet.
6. Close the manifold hand valves and turn off vac-
Turn the pump on and watch the low side gauge.
uum pump, watching the low side gauge reading.
The pump should pull the system into a vacuum
If vacuum remains for a few minutes, the system
(if not, the system has a leak).
is ready for charging.
3. Run the pump for five minutes and close the hand
NOTE: If using a recycling and charging machine, the
valves and shut off the pump.
vacuum pump is built into the unit. Separate hook-up
is not required.

TROUBLESHOOTING
PRE-DIAGNOSIS CHECK System Ducts and Doors - Check the ducts and
doors for proper function.
If the system indicates Insufficient cooling, or no cool-
ing, the following points should be checked befor Refrigerant Charge - Make sure system is prop-
proceeding with the system diagnosis procedures. erly charged with the correct amount of refriger-
ant.
NOTE: If the truck being serviced is a Model 930E, be
certain the Rest Switch in the cab is ON. Place the GF
PRELIMINARY STEPS
Cutout Switch in the CUTOUT position. (Refer to Fig.
3-1, Page E3-2, Propulsion System, for switch loc - The following steps outline the correct procedures
tion.) necessary to prepare the truck and the system for
testing and diagnosis:
PREPARING FOR DIAGNOSIS
1. Correctly connect the manifold gauge set to th
Successfully servicing an air conditioning system, b - system. Refer to the connection and purging pro-
yond the basic procedures outlined in the previous cedures outlined in this section.
section, requires additional knowledge of system test -
2. Run the engine with the air conditioning system on
ing and diagnosis.
for five to ten minutes to stabilize the system.
A good working knowledge of the manifold gauge set
3. With the engine and the system at normal operat -
is required to correctly test and diagnose an air condi-
ing temperature, conduct a Performance Test as
tioning system. An accurate testing sequence is usually
outlined in this section.
the quickest way to diagnose an internal problem.
When correctly done, diagnosis becomes an accurat
SYSTEM PERFORMANCE TEST
procedure rather than guesswork.
This test is performed to establish the condition of all
Compressor Belt - Must be tight, and aligned.
components in the system. Observe these conditions
Compressor Clutch - The clutch must engage. If during testing:
it does not, check fuses, wiring, and switches.
1. Start engine and operate at 1200 to 1500 RPM.
Oil Leaks - Inspect all connection or components
2. Place fan in front of condenser to simulate normal
for refrigeration oil leaks (especially in the ar
ram air flow and allow system to stablize.
of the compressor shaft). A leak indicates
refrigerant leak. 3. Place a thermometer in air conditioning vent clos-
est to evaporator.
Electrical Check - Check all wires and connec -
tions for possible open circuits or shorts. Check 4. Evaluate the readings obtained from the gauges
all system fuses. to see if they match the readings for the ambient
temperature.
Note: Some systems use different safety devices in the
compressor circuit to protect the compressor. Check As preliminary steps to begin checkout of the system,
the thermal fuse, the low pressure cutout switch, high perform the following:
pressure cutout switch or trinary pressure switch if
1. Close all windows and doors to the cab.
equipped.
2. Set air conditioning system at maximum cooling
Cooling System - Check for correct cooling sys-
and blower speed operation.
tem operation. Inspect the radiator hoses, heater
hoses, clamps, belts, water pump, thermostat 3. Readings on the two manifold gauges should b
and radiator for condition or proper operation. within normal range, adjust for ambient temper -
ture.
Radiator Shutters - Inspect for correct operation
and controls, if equipped. 4. Compare evaporator discharge air temperature
reading to see if it matches the recommended
Fan and Shroud - Check for proper operation of
temperature for the ambient temperature and
fan clutch. Check installation of fan and shroud.
gauge readings obtained.
Heater/Water Valve - Check for malfunction or
leaking.

5. Carefully feel the hoses and components on th DIAGNOSIS OF GAUGE READINGS & SYSTEM
high side. All should be warm-hot to the touch. PERFORMANCE
Check the inlet and outlet of receiver-drier for even
The following Troubleshooting Chart lists typical mal-
temperatures, if outlet is cooler than inlet, a re -
functions encountered in air conditioning systems. In-
striction is indicated.
dications and or problems may differ from one system
to the next. Read all applicable situations, service pro-
cedures, and explanations to gain a full understanding
of the system malfunction. Refer to information listed
under “Suggested Corrective Action” for service pro-
Use extreme caution when placing hands on high cedures.
side components and hoses. Under certain condi -
tions these items can be extremely hot.
6. Feel the hoses and components on the low side.
They should be cool to the touch. Check connec-
tions near the expansion valve, inlet side should
be warm and cold-cool on the outlet side.
7. If these conditions are met, the system is consid-
ered normal. Shut down engine. Remove gauges
and install the caps on the service valves.

– – – TROUBLESHOOTING BY MANIFOLD GAUGE SET READINGS – – –
Possible Causes Suggested Corrective Action
TROUBLE: Insufficient Cooling

Indications:
Low side pressure LOW.
High Side Pressure LOW.
Discharge air is only slightly cool.
Low refrigerant charge, causing pressures to b

slightly lower than normal. Check for leaks by performing leak test.
No Leaks Found:
1. Charge System
2. Performance Test System
Leaks Found:
1. If a leak is present at a connection, tighten th

connection, then add refrigerant as required.
2. If a system component needs to be replaced, r -
cover all refrigerant from the system. Replac
the defective part, then check the compressor
oil level; refill compressor oil as necessary.
3. Evacuate system.
4. Charge system with new / recycled refrigerant.
5. Check A/C operation and do system
performance test.
TROUBLE: Little or No Cooling
Indications:
1. Add Refrigerant (make sure system has at least
Low side pressure VERY LO
50% of its normal amount) and leak test system.
High side pressure VERY LO
Discharge Air Warm 2. It may be necessary to use a jumper wire to en-
No bubbles observed in sight glass, able the compressor to operate, if the compres-
may show oil streaks. sor has shut down due to faulty pressur
sensing switch.
Pressure sensing switch may have compressor
clutch disengaged.
Refrigerant excessively low; leak in system.
5. Evacuate system.
performance test.

Extremely Low Refrigerant Charge in the System
Indications:
Low side pressure LOW.
High Side Pressure LOW.
Air from vents in the cab seems warm.
If there is a low pressure switch in th
system, it may have shut off the com-
pressor clutch.
Extremely low or no refrigerant in the system. There Check for leaks by performing leak test.
may be a leak in the system.
No Leaks Found:
1. Add refrigerant to the system (at least half of th
normal full charge amount).
2. Performance test system.
Leaks Found:
2. It may be necessary to use a jumper wire to en-
able the compressor to operate, if the compres-
sor has shut down due to faulty pressur
sensing switch.
4. Evacuate system.
performance test.
Air and/or Moisture in the System

Indications:
Repair Procedure:-
Gauge Reading- Low Side Normal
Test for leaks, especially around the compres-
High Side Normal
sor shaft seal area. When the leak is found,
Air and/or Moisture in the System
recover refrigerant from the system and repair
the leak. Replace the receiver-drier or accumul -
High Side Normal
tor because the desiccant may be saturated
Cause- Air and/or moisture in the system. with moisture. Check the compressor and r -
place any refrigerant oil lost due to leakage.
The air from the vents in the cab is only slightly
Evacuate and recharge the system with refriger-
cool. In a cycling type system with a thermo-
ant, then check AC operation and performance.
static switch, the switch may not cycle the
clutch on and off, so the low pressure gaug
will not fluctuate.

Excessive Air and/or Moisture in the System
Indications:
Gauge Reading- Low Side High
High Side High Repair Procedure: Test for leaks, recover refriger-
Air from the vents in the cab is only ant from the system and repair the leak. De-
slightly cool. pending on the type of system, replace th
receiver-drier or accumulator. Check and r -
Cause- System contains excessive air and/or mois-
place any compressor oil lost due to leakage.
ture.
Evacuate and recharge the system, then check
AC operation and performance.
Expansion Valve Stuck or Plugged

Indications:
Test: Warm diaphragm and valve body with your
Gauge Reading- Low Side Low or Vac-
hand, or very carefully with a heat gun. Activat
uum
system and watch to see if the low pressur
High Side High
gauge rises.
Air from vents in the cab is only slightly
Next, carefully spray a little nitrogen, or any sub -
cool.
stance below 32° F, on the capillary coil (bulb)
The expansion valve body is frosted or
or valve diaphragm. The low side gauge needle
sweating.
should drop and read at a lower (suction) pres-
Cause- An expansion valve malfunction could mean sure on the gauge. This indicates the valve was
the valve is stuck in the closed position, the filter part way open and that your action closed it.
screen is clogged (block expansion valves do not Repeat the test, but first warm the valve di -
have filter screens), moisture in the system has fro - phragm or capillary with your hand. If the low
zen at the expansion valve orifice, or the sensing side gauge drops again, the valve is not stuck.
bulb is not operating. If the sensing bulb is accessi -
Repair Procedure: Inspect the expansion valv
ble, perform the following test. If not then proceed to
screen (except block type valves). To do this, r -
the Repair Procedure.
move all refrigerant from the system. Discon-
nect the inlet hose fitting from the expansion
valve. Remove, clean and replace the screen,
then reconnect the hose. Replace the receiver-
drier. Then evacuate and recharge the system
with refrigerant, and check AC operation and
performance. If the expansion valve tests did
not cause the low pressure gauge needle to ris
and drop, and if the other procedure described
did not correct the problem, the expansion
valve is defective. Follow the procedure for com -
ponent replacement.

Expansion Valve Stuck Open
Indications:
Test: Operate the AC system on it’s coldest setting
for a few minutes. Carefully spray a little nitro-
High Side Normal
gen or other cold substance, on the capillary
Air from vents in cab is warm or only
tube coil (bulb) or head of the valve.
slightly cool.
The low pressure (suction) side gauge needle
Cause- The expansion valve is stuck open and/or th should now drop on the gauge. This indicates
capillary tube (bulb) is not making proper contact the valve has closed and is not stuck open. Re -
with the evaporator outlet tube. Liquid refrigerant peat the test, but first warm the valve di -
may be flooding the evaporator making it impossibl phragm by warming with hands.
for the refrigerant to vaporize and absorb heat nor- If the low side gauge shows a drop again, th
mally. In vehicles where the expansion valve sensing valve is not stuck. Clean the surfaces of the
bulb is accessible, check the capillary tube for evaporator outlet and the capillary coil or bulb.
proper mounting and contact with the evaporator Make sure the coil or bulb is securely fastened
outlet tube. Then perform the following test if th to the evaporator outlet and covered with insul -
valve is accessible. If it is not, proceed to the Repair tion material. Operate the system and check
Procedure. performance.
Repair Procedure: If the test did not result in
proper operation of the expansion valve, th
valve is defective and must be replaced. Re-
cover all refrigerant from the system and r -
place the expansion valve and th
receiver-drier. Evacuate and recharge the sys-
tem with refrigerant, then check AC operation
and performance.
System High Pressure Side Restriction

Indications:
Repair Procedure: After you locate the defective
Gauge Reading- Low Side Low
component containing the restriction, recover
High Side Normal to High
all of the refrigerant. Replace the defective com -
Air from vents in the cab is only slightly
ponent and the receiver-drier. Evacuate and r -
cool.
charge the system with refrigerant, then check
Look for sweat or frost on high sid
AC operation and performance.
hoses and tubing, and frost appearing
right after the point of restriction.
The hose may be cool to the touch near
the restriction.
Cause- There could be a kink in a line, or other r -
striction in the high side of the system.

Compressor Malfunction
Indications:
Repair Procedure: If the belt is worn or loose, r -
place or tighten it and recheck system perform-
High Side Low
ance and gauge readings. If inspection of th
The compressor may be noisy when it
compressor is required, all of the refrigerant
operates.
must be recovered and the compressor disas-
sembled to the point that inspection can be per-
Cause- Defective reed valves or other compressor formed. Replace defective components or
components. If the compressor is not noisy, ther replace the compressor. If particles of desic -
may be a worn or loose compressor clutch drive belt. cant are found in the compressor, flushing of
the system will be required. It will also be neces-
sary to replace the receiver-drier. Always check
the oil level in the compressor, even if a new
unit has been installed. Rotary compressors
have a limited oil reservoir. Extra oil must b
added for all truck installations. Tighten all con-
nections and evacuate the system. Recharge
the air conditioner with refrigerant and check
the system operation and performance.
Condenser Malfunction or System Overcharge

Indications:
Repair Procedure: Inspect the condenser for dirt,
bugs or other debris and clean if necessary. Be
High Side High
sure the condenser is securely mounted and
The air from the vents in the cab may b
there is adequate clearance (about 1-1/
warm.
inches) between it and the radiator. Check the
The high pressure hoses and lines will
radiator pressure cap and cooling system, in-
be very hot.
cluding the fan, fan clutch, drive belts and radia-
Check the engine cooling system com-
tor shutter assembly. Replace any defectiv
ponents, fan and drive belt, fan clutch
parts and then recheck the AC system oper -
operation, and the radiator shutter.
tion, gauge readings and performance.
Cause- The condenser is not functioning correctly or
If the problem continues, the system may b
there may be an overcharge of refrigerant inside th
overcharged. Recover the system refrigerant
system. Another possibility is lack of air flow through
slowly until low and high pressure gauges read
the condenser fins during testing. Engine cooling
below normal. Then add refrigerant until pres -
system component malfunction can cause high pres-
sures are normal. Add another quarter to half
sure by blocking air flow (radiator shutter) or not pro-
pound of refrigerant and recheck AC system op-
viding air flow (fan clutch) in sufficient quantity.
eration, gauge readings and performance.
If the gauge readings do not change, all of th
refrigerant should be recovered and the system
flushed. The condenser may be partially
blocked - replace condenser. Also replace the
receiver-drier or accumulator. Evacuate the sys-
tem and check operation and performance.

Thermostatic Switch Malfunction
Indications:
Repair Procedure: Replace the thermostatic
switch. When removing the old thermostat, r -
High Side Normal
place it with one of the same type. Take care in
The low side gauge needle may fluctu-
removing and handling the thermostat and thin
ate in a very narrow range compared to
capillary tube attached to it. Do not kink or
a normal range.
break the tube.
The compressor clutch may be cycling
on and off more frequently than it should. Position the new thermostat capillary tube at or
The low side gauge needle may fluctu- close to the same location and seating depth
ate in an above normal range as th between the evaporator coil fins as the old one.
clutch cycles. This may be an indication Connect the electrical leads.
that the thermostat is set too high.
A new thermostat may have been in-
stalled incorrectly.
Cause- The thermostat switch is not functioning

properly or at all.

Preventive Maintenance Schedule for A/C System
Last Maintenance Check:________________________
Truck Serial Number:
Name of Service per-
Site Unit Number: ______________________________
NOTE: Compressor should be run at least 5 minutes

Date:______________Hour Meter:_________________
(40°F minimum ambient temperature) every month, in
order to circulate oil and lubricate components.
Maintenance Interval
COMPONENT (months)
Maintenance Interval
3 6 12 Done COMPONENT (months)
1. COMPRESSOR 3 6 12 Done
Check noise level • 4. EXPANSION VALVE
Check clutch pulley • Inspect capillary tub •
(if used) (leakage/dam-
Check oil level • age/
Run system 5 min. • looseness)
Check belt tension • 5. EVAPORATOR
(80 - 100 lbs; V-belt) Clean dirt, bugs, •
Inspect shaft seal • leaves, etc. from fins
(leakage) (w/compressed air)
Check mounting • Check solder joints on •
bracket (tighten bolts) inlet/outlet tubes (leak-
age)
Check alignment of •
clutch w/crankshaft Inspect condensate •
pulley (within 0.06 in.) drain
Perform manifold • 6. OTHER Components

gauge check Check discharge lines •
Verify clutch is • (hot to touch)
engaging Check suction lines •
2. CONDENSER (cold to touch)
Clean dirt, bugs, • Inspect fittings/clamps •

leaves, etc. from coils & hoses
(w/compressed air) Check thermostatic •
Verify engine fan • switch for proper op-
clutch is engaging (if eration
installed) Outlets in cab: 40°F to •
Check inlet/outlet for • 50°F temperature
obstructions/damage (HMS trucks: 25°F to
35°F below ambient)
3. RECEIVER - DRIER
Inspect all wiring •
Check inlet line from • connections
condenser (should b
hot to touch) Operate all manual •
controls through full
Replace if system is • functions
opened

NOTES

PAYLOAD METER II
ON BOARD WEIGHING SYSTEM (OBWS)
INDEX
GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-3
LIGHTS, SWITCHES, and COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-4
TIPS FOR OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-5
EXTERNAL DISPLAY LIGHTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-5
THEORY OF OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-6
Linkage Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-6
Brake Lock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-7
Calculation Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-7
Sources of Error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-7
Typical Data From Service Check Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-7
Example Calculation of Payload. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-8
Calculation of the Calibration Load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-8
TYPES OF DATA STORED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-9
Cycle data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-9
Engine ON/OFF Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-10
Fault Codes and Warning Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-10
Engine Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-11
Total Payload and Total Number of Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-11
Other Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-11
OPERATOR FUNCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-12
Using the Operator Load Counter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-12
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-12
Viewing the Operator Load Counter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-12
Clearing the Operator Load Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-12
Dimming the Lights on the Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-12
INITIAL SETUP OF PAYLOAD METER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-13
Switch Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-13
Checking the Operator Check Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-13
Checking the Service Check Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-14
Setting "UP:00". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-14
Setting "PL:00" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-14
Checking the Gt Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-14
Checking the Inclinometer Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-15
Calibrating a Truck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-15
DISPLAYS AT START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-16
SETUP AND MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-17
Setting the Speed Limit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-17
Setting the Option Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-17
Setting The Machine I.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-17
Setting The Operator I.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-18
Setting The Time and Date. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .M20-18
M20007 02/99 Payload Meter II M20-1

DOWNLOAD OF PAYLOAD AND FAULT CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-18
DISPLAY OF FAULT CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-19
CHARTS OF ERROR CODES AND OTHER INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20 & 21
SERVICE CHECK MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-22
Monitoring Input Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-22
UP Factor - Payload Calculation Gain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-23
PL Mode - Load Calculation Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-23
FINAL GEAR RATIO SELECTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-24
BATTERY REPLACEMENT PROCEDURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-25
Replacing the Battery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-25
After Replacing the Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-26
SUSPENSION PRESSURE SENSOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-26
Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-26
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-27
INCLINOMETER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-27
Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-27
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-27
SCOREBOARD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-28
Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-28
Making Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-28
Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-29
Normal Operation of the Scoreboard. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-30
PAYLOAD METER BACK PANEL CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-30
AMP Pin Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-31
PAYLOAD CIRCUIT NUMBER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-32
PAYLOAD METER II RE-INITIALIZATION PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M20-33
M20-2 Payload Meter II M20007 02/99

PAYLOAD METER II
ON BOARD WEIGHING SYSTEM (OBWS)
GENERAL INFORMATION The payload meter stores in memory various operating
data. This data includes:
The Payload Meter II On Board Weighing System
displays and records the payload weight along with 1) The payload, time, distance, and travel speed for
other operating information. The system consists of a each cycle.
payload meter, pressure sensors, deck mounted lights 2) The date and time that the engine was started and
and an inclinometer. stopped.
The payload meter (Figure 20-1) uses the four suspen- 3) The date and time of each fault that occurred or
sion pressures and an inclinometer to determine the was canceled.
load in the truck. The payload weight can be displayed
in short tons or metric tons. 4) The total payload and the overall number of cycles
for a specific time period.
There are three external deck-mounted lights on each
side of the truck. The lights indicate payload weight This data is retained even when the power is switched
divided into three separate stages. A forecast feature off. The stored data is backed up by an internal battery.
will flash a deck mounted light predicting the payload The data can be down loaded from the payload meter
weight if the next bucket of material is dropped into the to a personal computer when a communication cable
body. is connected to the port inside the cab.
FIGURE 20-1. PAYLOAD METER II

1. Display panel 7. Total/shift switch [TOTAL] [SFT]
2. Reception pilot lamp (Rx busy) 8. Light/increment switch [LIGHT] [INC]
3. Transmission pilot lamp (Tx busy) 9. Memory card
4. Memory card access lamp (CARD busy) 10. Cover
5. Mode switch [MODE] 11. Diagnostic/Download Port
6. Calibration/clear switch [CAL] [CLR]
WARNING - When not inserting or removing memory card (9), always keep the cover (10) closed)

LIGHTS, SWITCHES, and COMPONENTS
On The Face Of The Payload Meter
(Refer to Figure 20-1)
1. Display Panel 7. Total/Shift Switch
Digital display area for the data being recorded in Used to display payload and overall number of
memory. This will include items such as: cycles each time the load is dumped. Will display
Payload the error codes. This switch is also used with the
CALIBRATION/CLEAR switch to clear total pay-
Date & Time
load and overall number of cycles.
Cycles
8. Light/Increment Switch
Travel Distance
Used to change the digital increments or units for
Fault Codes and Warnings the various displays. Also used to adjust the
2. Reception Pilot Lamp (Rx Busy) brightness of the lights on the monitor display.
This light will illuminate for 3 seconds when the 9. Memory Card
system is powered up. It will then be lit whenever Used to receive data from the payload meter
the computer is communicating. memory to this card which can then be used to
3. Transmission Pilot Lamp (Tx Busy) transfer the data into a personal computer. This
enables the memory to be downloaded and saved
This light will illuminate for 3 seconds when the
when a personal computer is not available.
system is powered up. It will then be lit whenever
the memory is being downloaded to a personal 10. Cover
computer. Protective cover for the Memory Card. Do not
4. Memory Card Access Lamp (CARD Busy) open or place foreign objects in slot.
This light will illuminate for 3 seconds when the 11. Diagnostic/Download Port
system is powered up. It will also be lit whenever Connector port that is used for downloading the
the memory data is being downloaded to the memory data to a personal computer.
memory card.
5. Mode Switch
This switch is used to select the mode or system
that will allow a function to be performed.
This may include:
Various settings or corrections to the display
Memory card downloading
Clearing data
Display of Abnormalities or Warnings
Setting the speed limit
Setting the date and time
6. Calibration/Clear Switch
Used to calibrate the machine when the condi -
tions regulate this action.
Also used with the TOTAL/SFT switch to clear
total payload and overall number of cycles.

TIPS FOR OPERATION EXTERNAL DISPLAY LIGHTS
To assure that the On Board Weighing System records The Payload Meter II controls three light relays. The
the most accurate and consistent data, these impor - relays operate three deck mounted lights on each side
tant steps should be followed: of the truck. There is one green light, one amber light,
and one red light. (Figure 20-3)
* For most Haulpak Trucks:
Use only the Brake Lock switch to hold the truck While the truck is stopped being loaded and the hoist
stationary at the loading and dumping area. lever is in the float position, the appropriate lights will
For 330M Haulpak Trucks ONLY: remain on according to the following schedule:
Use the Park Brake switch to hold the truck
stationary at the loading and dumping area.
Any other method will not allow the payload sys-
tem to register properly.
* Do not activate the “Lamp Test” switch during
loading. Inaccurate and inconsistent data may be
stored.
* At the loading area do not release the Brake Lock
(or Park Brake switch) until the loading is com-
plete and the load shock from the last load
dumped has settled.
* The loading area surface must be maintained as
flat and level as possible. The On Board Weighing
FIGURE 20-2. LOAD INDICATOR LIGHTS
System can compensate for slight variations in
grade and unevenness, but ruts, berms, rocks,
INDICATOR LIGHT PAYLOAD WEIGHT
etc. will cause the system to record inaccurate
and inconsistent data. Off Off Green 50% and Greater
Off Amber Green 90% and Greater
* Regularly remove “carryback” from the dump body.
RED Amber Green 105% and Greater
* Calibrate periodically.
The shovel or loader operator can predict the payload

weight by observing these lights. During the loading
operation, a forecast feature flashes a deck mounted
light predicting the payload weight after the next bucket
of material is loaded into the body.
The logic is as follows:
1. If the measured payload is varying 3% or less of
the rated load for more than 3 seconds, the
current load is deemed a steady value.
2. If the difference between the previous steady
value and the current steady value is greater than
15% of the rated load, the difference is taken to
be the size of the current bucket.
3. The average size of previous buckets is added to
the current load. One of the deck mounted lights
will turn on, if another “average” size load is put
in the body, and will blink at one second intervals.

THEORY OF OPERATION Linkage Factor
The linkage factor is part of the complex calculations
Basic Description performed by the payload meter to determine the load
The payload meter uses the four suspension pres - in the truck. The linkage factor is dependent on the load
sures and the inclinometer to determine the load in the on the rear suspensions.
truck. These inputs are critical to the calculation of the Figure 20-3 shows the side view of a truck. The nose
load. The other inputs to the payload meter (Body Up, pin is marked with a star and there are three arrows
Speed, Brake Lock, Alternator R Terminal, and Engine pointing to different spots of the rear tire. This figure
Oil Pressure) are used to indicate where the truck is in shows how the support under the rear tire can affect
the haul cycle. These inputs enable the payload meter the calculation of the load. The payload meter does not
to make time and distance measurements for the haul directly measure the load transferred to the frame
cycle. through the nose pin. To account for portion of the load
The suspension pressures are the key ingredients in carried by the nose pin, the linkage factor is multiplied
determining the sprung weight of the truck. These by the rear suspension force. It is assumed that the
pressures are converted into forces using the formulas truck is supported under the center of the tire. In this
shown below. These forces are combined with the case the payload meter uses L2 to help compute the
geometry of the truck to produce the load calculation. linkage factor. If, however, the truck is backed into a
It is critical that the suspension pressure sensors are berm and the rear tire is supported towards the back
functioning properly. of the tire, the actual linkage factor calculation should
use L3. Since the payload meter assumes L2 it will
overestimate the load in the truck. The opposite is true
in the case where the rear tires are supported toward
the front of the tire. The linkage factor should use L1
π 2
Sprung Weight =
4
Suspension Diameter (Psi Left + Psi Right) but the payload meter assumes L2. This change in
leverage will cause the payload meter to underesti -
Sprung Weight = Axle Weight(lbs)/2000 mate the load.
The inclinometer gives the payload meter information

regarding the pitch angle of the truck. The front and
rear incline factors are determined by the pitch angle.
These two factors account for the load transfer that
occurs when the truck is inclined nose up or nose
down.
Figure 20-3.

Brake Lock Typical Data From Service Check Mode
The Brake Lock only applies the rear brakes. This
Number Data Description
allows the front wheels to rotate slightly as the truck is
being loaded. This is important because the payload 1 13:09 Current Time
meter assumes that the front wheels can rotate freely. 2 749.4 Front Left Pressure (Psi)
As the truck is being loaded, it will begin to squat down 3 848.9 Front Right Pressure (Psi)
on the suspensions. This will change the wheel base
4 863.2 Rear Left Pressure (Psi)
dimension of the truck. This freedom of movement
prevents additional binding and friction in the front 5 1049.0 Rear Right Pressure (Psi)
suspensions. 6 106.0 Front Weight (Tons)
The incline of the grade on which the truck is loading 7 75.1 Rear Weight (Tons)
is measured by the inclinometer. This helps determine 8 -1.85 Inclinometer (Degrees)
the incline factors that are applied to the front and rear 9 0.95 Incline Factor - Front Wheels
sprung weights. The tire forces on the road surface that
10 0.984 Incline Factor - Rear Wheels
hold the truck on grade affect the suspension pres-
sures. If the front and rear brakes are locked, the effect 11 1 Link Factor - Front Wheels
on the suspension pressures cannot be determined. 12 1.539 Link Factor - Rear Wheels
If only the rear brakes are applied the effect is predict- 13 70.6 Calibration Sprung Weight (Tons)
able and the incline factors accurately account for the
14 1.000 Gain Adjustment
forces on the tires.
15 143.8 Current Load (Tons)
If the service brake or park brake is used and depend-
16 3.9 Battery Backup Voltage (Volts)
ing on the incline and other factors, the payload meter
can overestimate or underestimate the load. It is im-
Figure 20-4.
portant that only the Brake Lock be used while
loading the truck. A sample data set is shown in Figure 20-4. This data
was taken in the laboratory and is used in Figure 20-5
Sources of Error to calculate the final load. Note that the front suspen -
sion pressures were converted into the front sprung
Suspensions weight using the formulas above Figure 20-5. The front
sprung weight is then multiplied by the front incline
Poorly charged suspensions can lead to systematic factor and the front linkage factor. The same is done
error in the calculation of payload. The error is most with the rear sprung weight. The front and rear sprung
obvious when the oil level is low. When there is too weights are then summed. This number is multiplied
little oil in the suspensions, the cylinder may compress by the Gt gain potentiometer value. This value should
completely under load. The weight of the truck will be be 1.000. The calibration load is subtracted from the
carried by the metal to metal contact within the sus - total to produce the final load. The load displayed on
pension. Not only will the ride of the truck and the life the meter is this final load (item #15) multiplied by the
of the tires be affected, but the pressure in the cylinder UP gain factor.
will not truly represent the load on the truck. In the
under-charged condition the payload meter will typi - Note - This screen is the only place that the value of
cally weigh light and under report the load. the Gt gain potentiometer can be checked. THIS GAIN
SHOULD BE SET TO 1.000. ANY OTHER SETTING
CAN PRODUCE SYSTEMATIC ERRORS IN THE
PAYLOAD MEASUREMENT.
Note - There are two gain factors that can be applied
to the payload measurement. The first is the Gt gain
factor and the other is the UP gain factor. They are not
applied uniformly to all payload calculations. Both gain
factors should be set to 1.000. See the warning on
page 16 for more information.
If the G t gain factor displayed in the Service Check
Mode is not 1.000, adjust the gain to exactly 1.000.

In order to adjust this gain: Calculation of the Calibration Load
1. Start with the payload meter in normal operation This procedure is similar to the manual calculation of
mode. load. This calibration load is used as item #13 from the
manual calculation procedure.
2. Adjust the gain pot, left to reduce the value and
right to increase the value. 1. Press and hold the LIGHT/INC and
MODE switches until "CHEC" is flash-
3. Press and hold the LIGHT/INC and ing on the display.
MODE switches until "CHEC" is
flashing on the meter. 2. Press and hold the CAL/CLR switch
until "CALL0" is flashing on the display.
4. Press and hold the LIGHT/INC
switch until "ALL0" is flashing on 3. Press the CAL/CLR switch to cycle through the
the display. "A.FUL" may also be displayed. following data. The sequence repeats.
5. Press the LIGHT/INC switch14 times. The number
displayed will be the current Gt gain. This is not a
"live" reading. Any time the potentiometer is Item and Description Units
changed, this cycle must be repeated to view the 1. Year of Calibration Last 2 digits of year
change.
2. Month:Day of Calibration XX:XX
6. Press MODE once and "CHEC" will 3. Hour:Minute of Calibration XX:XX
flash on the display. 4. Truck Model Setting
5. Pressure Front Left Psi
7. Press MODE once and the meter will return to
normal operation. 6. Pressure Front Right Psi
7. Pressure Rear Left Psi
These calculations used a 13" front suspension diame-
ter and 10" rear suspension diameter. 8. Pressure Rear Right Psi
π 2
9. Front Sprung Weight Tons
Sprung Weight = Suspension Diameter (Psi Left + Psi Right)
4 10. Rear Sprung Weight Tons
Sprung Weight = Axle Weight(lbs)/2000 11. Degree of Incline ±° Nose Up Positive
Example Calculation of Payload 12. Incline Factor - Front Axle
13. Incline Factor - Rear Axle
Front Weight (6) 106.00 Rear Weight(7) 75.10 14. Link Factor Front Axle
X Incline Factor (9) 0.95 X Incline Factor (10) 0.98 15.Link Factor Rear Axle
100.70 73.90 16. Calibration Weight Tons
X Link Factor (11) 1.00 X Link Factor (12) 1.53
Front Weight 100.70 Rear Weight 113.70
4. Press MODE once and "CHEC" will

Front Weight 100.70 flash on the display.
Rear Weight 113.70
Total Weight 214.40 5. Press MODE once and the meter will return to
normal operation.
XGain Factor (14) 1.00
214.40
- Calibration (13) -70.60
Current Load(15) 143.80
Figure 20-5.

TYPES OF DATA STORED
Cycle Data
One cycle is considered to be from the point where a load is dumped to the point where the next o
l ad is dumped.
Data between these two points is recorded in memory. Examples of the data are shown below. The maximum
number of cycles that can be stored in memory is 2900 cycles.
ITEM UNIT RANGE REMARK

Advances by one each time the
Engine Operation Number Number 1 - 65535
engine is started.
Month Month 1 - 12
Day Day 1 - 31
These values are stored when the
Time Hour Hour 24 Hour Clock
load is dumped.
Time Minute Minute 1 - 59
Metric tons
Payload 0 - 6553.5
Short tons
Travel Time When Empty Minute 0 - 6553.5
Travel Distance When Empty Miles/Km 0 - 25.5
Maximum Travel Speed When Empty Mph/Kmh 0 - 99
Average Travel Speed When Empty Mph/Kmh 0 - 99
Time Stopped When Empty Minute 0 - 6553.5
Time Stopped During Loading Minute 0 - 6553.5
Travel Time When Loaded Minute 0 - 6553.5
Travel Distance When Loaded Miles/Km 0 - 25.5
Maximum Travel Speed When Loaded Mph/Kmh 0 - 99
Average Travel Speed When Loaded Mph/Kmh 0 - 99
Time Stopped When Loaded Minute 0 - 6553.5
Dumping Time Minute 0 - 6553.5
Speed Limit Mph/Kmh 0 - 99
Warnings For Each Cycle The fault codes that occur during each cycle

Engine ON/OFF Data
When the engine is started or stopped, the following data is recorded.

Advances by one each time the
Engine Operation Number Number 1 - 65535
engine is started.
Last Two Digits Of The Year Year 0 - 99
Month Month 1 - 12
Indicates when the engine was
Day Day 1 - 31 started.
Last Two Digits Of The Year Year 0 - 99
Month Month 1 - 12 Indicates when the engine was
Day Day 1 - 31 shut off.
Total payload from the time when
Metric tons
Total Payload 0 - 999900.0 the engine was started until the
Short tons
time the engine was shut off.
Totals for the time that the engine
Total Number Of Cycles Number 0 - 9999
was running.
The engine operation numbers are included in the fault and warning data.
Fault Codes and Warning Data

Displayed by a combination of letters and numbers representing a specific
Error Code
error code.
Engine Operation Number Every time the engine is started
Number 1 - 65535
At Time Of Occurrence the number advances by one.
Number Of Times Of Occurrence Since
Number 1 - 255
The Engine Was Switched ON
Last Two Digits Of Year Year 0 - 99
Month Month 1 - 12
Day Day 1 -31

Engine Operation
ITEM UNIT RANGE REMARKS

Every time the engine is started
Number when Canceled Number 1 - 65535
the number advances by one.
Month Month 1 - 12
Day Day 1 - 31
NOTE: If the engine operation number is a 0, this indicates that the problem occurred or was canceled (depends on
the operation that was performed) when the key switch was in the ON position and the engine was not running.
Total Payload and Total Number of Cycles

The total payload and overall number of cycles can be displayed using the forced display operation. Both values
start from a zero point whenever the memory has been cleared. The payload total is automatically displayed when
the load is dumped.

Metric Tons The total payload since the unit
Total Payload 0 - 999900.0
Short Tons was cleared.
The number of cycles since the
Total Number Of Cycles Digital Number 0 - 9999
unit was cleared.
Month Month 1 - 12 Date and time the unit was
Day Day 1 - 31 cleared.
Other Data
CONTENT ITEM UNIT RANGE REMARKS
Set Up Data That The Speed Limit Km/MP 0 - 99
Operator Can Check Option Code Digital Number 0 - 13 Communication Mode
Year Year 0 - 99
Month Month 1 - 12
Calibration Data Day Day 1 - 31 Date and time when calibrated.
Hour Hour 24 Hour Clock
Minute Minute 0 - 59

OPERATOR FUNCTIONS Clearing the Operator Load Counter
1. Press the TOTAL/SFT switch once. The number
Using the Operator Load Counter displayed is the total tons hauled since the last
time the counter was cleared. The total is dis -
Description played in hundreds of tons.
The Payload Meter makes available to the operator a
Total Load Counter and Haul Cycle Counter. This
allows each operator to track the tons hauled during 2. Press and hold the CAL/CLR switch until the
their shift. The total is displayed in hundreds of tons. display flashes.
For example, if 223 is displayed, this means that
22,300 tons have been hauled since the last time the
cycle counter was cleared. 3. Press the CAL/CLR switch until "0000" is dis -
played. After 2 seconds the meter will return to
This memory location is separate from the main pay - normal operation.
load data storage. This memory is not cleared when
the Data All Clear Operation is performed. Clearing Clearing this memory does not affect the main pay-
this memory does not affect the main payload data load data storage.
storage.
Viewing the Operator Load Counter Dimming the Lights on the Display
1. Press the TOTAL/SFT switch once. There are a total of 10 brightness levels on the PLM
If there is a fault code present at this time: display.
2. The error code for that problem will be displayed.
This will be a flashing display. From the normal operation display:
3. Press the TOTAL/SFT switch again. If additional 1. Press the LIGHT/INC switch. The lighting will
faults or warnings exist, that fault code will be become one level dimmer. This will continue until
displayed as a flashing code. the lighting has reached its lowest level.
4. Repeat step #3 until no fault codes are displayed. 2. After reaching the lowest level, the display will
":" will show when no additional faults exist. The return to the brightest setting.
display will then show total tons hauled since the
last time the counter was cleared. The total is If the switch is held in the depressed position, the
displayed in hundreds of tons. brightness will change continuously.
5. Press the TOTAL/SFT switch again. The number
displayed is the number of haul cycles since the
last time the cycle counter was cleared.
6. Press the TOTAL/SFT switch again. ":" is dis -
played for 2 seconds before the display returns to
normal operations.

INITIAL SETUP OF PAYLOAD METER There are nine switches located behind the panel on
the left side of the payload meter. Figure 20-8 shows
There are several things that must be checked and the switch numbers. The following switch positions
programmed when a Payload Meter is first installed. should be confirmed before the meter is installed.
1. Check the Switch Settings on the side of the
Switch Position
meter.
1 Gt Gain - Do Not Adjust
2. Check the Operator Check Mode settings
B Buzzer Volume - Do not Adjust
3. Check the Service Check Mode settings 2 7
4. Calibrate the clean truck. 3 7
The next few pages show the steps required to perform 4* 4 - 685E
these checks. Only after all of these steps have been 5 - 630E
performed can the payload meter be released for B - 730
service.
C - 930E
D - 530M
E - 330M
Switch Settings
F - 830E
5 DOWN
6 DOWN
7 DOWN - SHORT TONS
UP - METRIC TONS
8 UP
* Set switch 4 for the appropriate model.
Checking the Operator Check Mode

The Operator Check Mode is used to check and
change several settings. These should be checked
before the payload meter is put into service.
1. Press and hold the MODE
switch. The display will show.
2. Press the MODE switch once.

The display will show.
Refer to "Data All Clear" on Page 17 to clear the
haul cycle data.

Refer to "Display of Fault Codes" on Page 19 for
Figure 20-6. viewing fault codes.

This is the truck ID number. Refer to "Setting The
Machine ID" on Page 18 to change Machine ID.

5. Press the MODE switch once.The Setting "PL:00"
display will show. Refer to "Setting
1. Press and hold the LIGHT/INC and MODE
The Operator ID" on Page 18 to change operator.
switches. The display will show.
6. Press the MODE switch once. The
display will show."SP:62" should be
2. Press and hold the LIGHT/INC and TOTAL/SFT
displayed. The speed limit should
switches.
be set to 62 to avoid unnecessary faults and
warnings. Refer to "Setting The Speed Limit" on
Page 17 to make adjustments.
3. Press the CAL/CLR switch once.
7. Press the MODE switch once. The display will show.
The display will show. Refer to
"Setting The Option Code" on 4. Press the CAL/CLR switch once.
Page 17 to change the option. The display will show.
5. Press the LIGHT/INC switch until
The current time should be dis -
"PL : 00 " i s di spla yed. ONLY
played with the minutes flashing.
"PL:00" IS RECOMMENDED.
Refer to "Setting The Time And Date" on Page 18
to change the time and date.
6. Press the MODE switch.
9. Push the MODE switch to return to normal opera-
tion.
7. Press MODE and the meter will return to normal
Checking the Service Check Mode operation.
Checking the GT setting

The Gt value must be set = 1.000. Refer to "Calculation
Refer to Pages 23 and 24 for additional information Method" on Page 8 for display and adjustment infor-
on UP Factor and PL Modeprior to setting these mation.
values.
Checking the Inclinometer Settings
Setting "UP:00"
Refer to "Calculation Method" for instructions to dis -
1. Press and hold the LIGHT/INC and play truck pitch angle. With truck on level ground,
MODE switches. The display will properly charged suspensions, and empty the display
show. should indicate 0.0± 1.0. Remember this is not a live
display. After adjustment, Service Check Mode must
2. Press and hold the LIGHT/INC and be entered again to obtain a new reading.
TOTAL/SFT switches. The display
will show. An alternative method is to use a Personal Computer
running the Komatsu Payload Download Program for
3. Press the CAL/CLR switch once. windows. The "Monitor Pressures" section of the pro-
The display will show. gram displays live inclinometer data. The inclinometer
can be loosened and adjusted until the live display
4. Press the LIGHT/INC switch until shows 0.0± 1.0 degrees with the truck on level ground,
"UP: 0" is displayed. ONLY "UP: properly charged suspensions, and empty.
0" IS RECOMMENDED. Another method is to use a voltmeter to read the
voltage output of the inclinometer. With the truck on
5. Press MODE. The display will level ground, properly charged suspensions, and
show.
empty, the output voltage should be 2.6± .1 volts.
6. Press MODE and the meter will return to normal
operation.

Calibrating a Truck
The payload meter should be calibrated whenever one
of the following occurs:
1. When a new payload meter is installed.
2. When a suspension sensor has been changed.
3. Whenever the suspensions have been serviced
or the Nitrogen levels have changed.
4. Once a month thereafter.
To calibrate the payload meter:
1. With the engine running and the truck stopped,
press and hold the CAL/CLR switch until "CAL" is
flashing on the display.
2. Drive the truck until the speed is approximately
6-10 MPH (10-15 Km/H)
3. Press the CAL/CLR switch once.
4. Drive until the display switches back to the time
of day. This will take up to 30 seconds.
5. The payload meter is now calibrated and ready
for normal operation.
Carry out this operation on flat level ground.

Travel in a straight line.
Maintain a steady speed, 6-10 MPH (10-15 Km/H)

DISPLAYS AT START-UP 7. The display will show:
POWER ON: This display indicates the Machine ID code where

“xxx” indicates a value between 0 and 200.
ALL external display lamps (Figure 20-2) will come on
and stay on for approximately 27 seconds during the
8. The display will show:
“Power-up Process”.
The “Power-up Process” will display the PLM settings. This display indicates the Operator ID code where
Each display will occur for approximately 3 seconds: “xxx” indicates a value between 0 and 200.

1. The display will show: This display indicates the Speed Limit setting
In addition, a buzzer will sound and the following where “xx” indicates a value between 0 and 99
lamps will light for 3 seconds: km/h.
•Reception Pilot Lamp (2, Figure 20-1) 10. The display will show:
•Transmission Pilot Lamp (3, Figure 20-1)
This display indicates the Option code setting.
•Memory Card Pilot Lamp (4, Figure 20-1)
Refer to “Operator Check Mode, Setting the Op-
2. The display will show: tion Code” and to “Method of Operation” for more
information on this function.
The “xx” indicates the Truck Model. Refer to
"Initial Setup of Payload Meter" for code defini -
tions.

This display indicates the status of
the Memory Card where: NORMAL OPERATION
“Cd : - -” indicates Card Not Used, and If the truck engine is started before the preceding
“Cd : oo” indicates Card Is Used. “Power-up Process” is completed, the display will shift
4. The display will show: to normal operation.
This display indicates the status of
the Inclinometer for the PLM,
where If the engine is running when the payload meter starts
up, only "o:XXX" and "d:XXX" will display before
“CL : - -” indicates Inclinometer Not Used, and switching to normal operations.
“CL : oo” indicates Inclinometer Is Used.

This display indicates method of
measurement where:
"US : - -" indicates METRIC Tons.

"US : oo" indicates U.S. Tons.

This function is not used.
"SU : - -" indicates Switch 8 is up.
"SU : oo" indicates Switch 8 is down.

SETUP AND MAINTENANCE 7. Press the LIGHT/INC switch to change the “tens
digit” to the desired number.
8.Press the MODE switch to return to normal opera-
Speed Limit tion.
A warning can be displayed if the machine exceeds a 9. The Option Code selects the PLM communication
preset speed. mode as follows:
The available range is: 10 - 99 km/h (6 - 62 mph). It is
recommended to set the speed limit to 99 km/h (62 Option
mph). COMMUNICATION MOD
Code
Setting The Speed Limit 0 Stand Alone

10 PMC Mode (530M only)
1. Press and hold the MODE switch
until "Cd:dP" is flashing. Modular Mining Mode, Scoreboard
12
and User Data Commmunication Mode
The display will show:
NOTES:
3. Press the MODE switch once. 1. The Option Code is set to “0" for trucks not
The display will show: equipped with Modular Mining System (MMS)
(Except 530M).
4. Press the MODE switch repeatedly
until "SP.XX" is displayed. 2. The 530M with Powertrain Management Control
(PMC) system uses “10" as the setting for the
5. Press the LIGHT/INC switch to change the “unit Option Code.
digit” to the desired number. 3. For trucks with Modular Mining System (MMS) or
6. Press the TOTAL/SFT switch Scoreboard, the Option Code is “12".
and the display will then indicate:
Setting The Machine I.D. Code
7. Press the LIGHT/INC switch to change the “tens 1. Press and hold the MODE switch
digit” to the desired number. until "Cd:dP" is displayed.
8.Press the MODE switch to return to normal opera-
tion. 2. Press the MODE switch once.
Setting the Option Code
1. Press and hold the MODE switch The display will show:
until "Cd:dP" is displayed.
2. Press the MODE switch once. "d.XXX" is displayed.
5. Press the LIGHT/INC switch to change the last
3. Press the MODE switch once. digit to the desired number.
The display will show: 6. Press the TOTAL/SFT switch
and the display will show:
4. Press the MODE switch repeatedly
until "OP.XX" is displayed. 7. Press the LIGHT/INC switch to change the middle
digit to the desired number.
5. Press the LIGHT/INC switch to change the “unit
digit” to the desired number. 8. Press the TOTAL/SFT switch
and the display will show:
6. Press the TOTAL/SFT switch
and the display will then indicate:

9. Press the LIGHT/INC switch to change the first 7. Press the LIGHT/INC switch to change the hours.
digit to the desired number. The clock is a 24 hour clock.
10. Press the MODE switch to return to normal op- 8. Press the TOTAL/SFT switch and
eration. the display will then indicate:
Setting The Operator I.D. Code 9. Press the LIGHT/INC switch to change the day.
1. Press and hold the MODE switch 10. Press the TOTAL/SFT switch and
until "Cd:dP" is displayed. the display will then indicate:
2. Press the MODE switch once. The 11. Press the LIGHT/INC switch to change the month.
display will show:
12. Press the TOTAL/SFT switch and
the display will then indicate:
display will show:
13. Press the LIGHT/INC switch to change the year.
4. Press the MODE switch repeatedly 14.Press the MODE switch to return to normal opera-
until "o.XXX" is displayed. tion.
5. Press the LIGHT/INC switch to change the last DOWNLOAD OF INFORMATION

digit to the desired number.
Payload information and fault codes recorded should
6. Press the TOTAL/SFT switch and be downloaded to a personal computer on a regular
the display will then indicate: basis. The software required is available under part
number AK4094. Detailed instructions for installing the
7. Press the LIGHT/INC switch to change the middle software and downloading the data is provided with
digit to the desired number. AK4094 PLM II download software.
the display will show: Data All Clear
This function will erase all of the cycle data, engine
9. Press the LIGHT/INC switch to change the first ON/OFF data, and fault/warning data. Total payload
digit to the desired number. and the overall number of cycles will not be cleared.
10. Press the MODE switch to return to normal op- IMPORTANT - Before clearing the data, download
eration. the data to a personal computer.
Setting The Time and Date To begin, the shift lever should be in the “N
position, the brake lock set, the hoist control lever
1. Press and hold the MODE switch should be in the “FLOAT” position and the body in
until "Cd:dP" is displayed. the down position.
2. Press the MODE switch once. The 1. Press and hold the MODE switch
display will show: until "Cd:dP" is displayed.
3. Press the MODE switch once. The 2. Press the MODE switch once. The
display will show: display will show:
4. Press the MODE switch repeatedly 3. Press and hold the CAL/CLR
until "XX:XX" is displayed. switch until "A.CLE" is flashing.
5. Press the LIGHT/INC switch to change the min - 4. Press the CAL/CLR switch again and the memory
utes. will be cleared. The meter will then return to
normal operation.
the display will then indicate: This does not clear the Operator Load Counter.

DISPLAY OF FAULT CODES • Condition of the Engine Oil Pressure signal.
1. Press and hold the MODE switch The panel will display :C3:XX” for 3 seconds,
until "Cd:dP" is displayed. then indicate:
“ C3:oo” Engine is running.
display will show: “ C3:– –” Engine is not running.
• Condition of Alternator ’R’ terminal signal.
display will show: The panel will display C4:XX” for 3 seconds,
then indicate:
4. Press the TOTAL/SFT switch. “ C4:oo” Engine is running.
If there are no faults or warnings, “ C4:– –” Engine is not running.
the display will show for 6 seconds.
• Condition of the Spare Analog Input 1 signal.
If there are current faults or warnings, the codes The panel will display C5:XX” for 3 seconds
will be displayed in order of their priority, the with XX: as an input signal (V).
highest priority first. Each code will flash for 6
seconds. • Condition of the Spare Analog Input 2 signal.
5. After the current codes have been displayed, past The panel will display C6:XX” for 3 seconds
history codes that have been reset will be dis - with XX: as an input signal (V).
played. Each code will flash for 3 seconds. • Condition of the Spare Digital Input 1 signal.
If there are no history codes or
The panel will display C7:XX” for 3 seconds,
after all history codes have been
then:
shown , the display will show for 3
seconds: “ C7:oo” High.
The system will then proceed to the following “ C7:– –” Low.
displays: Refer to Page 22 for details.
• Condition of the Spare Digital Input 2 signal.
• Condition of the shift selector on mechanical trucks
or brake lock on electric trucks. The panel will display C8:XX” for 3 seconds,
then:
The panel will display: C1:XX” for 3 seconds,
then indicate: “ C8:oo” High.
Mechanical trucks “ C8:– –” Low.
“ C1:oo” Shift selector is in "N". 4. Press the TOTAL/SFT switch to view faults again
or press the MODE switch to return to normal
“ C1:– –” Shift selector is not in "N’. operation.
Electric trucks
“ C1:oo” Brake lock is on.
“ C1:– –” Brake lock is off.
• Condition of the Body Up Switch signal.
The panel will display: C2:XX” for 3 seconds,
then indicate:
“ C2:oo” Body up switch is in up position.
“ C2:– –” Body up switch is in down position.

Monitoring Input Signals Service Check Mode
This procedure can be used to monitor the current 1. Press and hold the LIGHT/INC and MODE
input signals to the payload meter. switches until "CHEC" is flashing.
1. Press and hold the LIGHT/INC and MODE 2. Press and hold the LIGHT/INC switch until "ALL0"
switches until "CHEC" is flashing. is flashing. "A.FUL" may also be displayed.
2. Press and hold the CAL/CLR and TOTAL/SFT 3. Press the LIGHT/INC switch to cycle through the
switches until "S.CHE" is flashing. following data. The sequence repeats.
3. Press the CAL/CLR switch to cycle through the Item and Description Units
following information :
1. Current Time Hours:Minutes
C1:oo - Shift Selector in "N" 2. Pressure Front Left Psi
C1 Mechanical Trucks C1:-- - Shift Selector 3. Pressure Front Right Psi
not in "N"
4. Pressure Rear Left Psi
C1:oo - Brake Lock On
C1 Electric Trucks 5. Pressure Rear Right Psi
C1:-- - Brake Lock Off
6. Front Weight Ton
C2:oo - Body Down
C2 Body Up 7. Rear Weight Ton
C2:-- - Body Up
C3:oo - Engine Run ±° Nose Up
C3 Engine Oil Pressure 8. Degree of Incline
C3:-- - Engine Stopped Positive
C4:oo -Alternator Charging 9. Incline Factor - Front Axle
C4 Alternator R Terminal
C4:-- - Alternator Stopped 10. Incline Factor - Rear Axle
C5 Analog 1 - Not Used 11. Link Factor - Front Axle
C6 Analog 2 - Not Used 12. Link Factor - Rear Axle
C7 Digital 1 - Not Used 13. Calibration Weight Ton
C8 Digital 2 - Not Used 14. Gt - Trimmer Gain
C9 Speed Vehicle Speed 15. Current Load Ton
Travel Distance - 16. Backup Battery Voltage Volts
C10 under t he current xx.xx Miles
loaded or empty state
03:01 - Empty Stopped 4. Press MODE once and "CHEC" will flash on the
Current Status 01:02 - Empty Traveling display.
Note: 06:03 - Loading 5. Press MODE once and the meter will return to
C11
Sample values are 02:04 - Loaded Traveling normal operation.
shown. 04:05 - Loaded Stopped
05:06 - Dumping
C12(a)* Time Empty Travel S1:xx - Minutes*10
C12(b) Time Empty Stopped S2:xx - Minutes*10
C12(c) Time Loaded Travel S3:xx - Minutes*10
C12(d) Time Loaded Stop S4:xx - Minutes*10
C12(e) Time Dumping S5:xx - Minutes*10
C12(f) Time Loading S6:xx - Minutes*10
* After 9.9 minutes, "S1:--" will be displayed.
4. Press the MODE switch once and "CHEC" will

flash.
5. Press the MODE switch once and the meter will
return to normal operation.

UP Factor - Payload Calculation Gain Careful consideration must be given to the use of
PL:01 and PL:10. These modes divide the data trans-
Description of UP Factor mitted by Modular Mining and the data stored in the
payload meter’s memory. Additionally, each mode
The payload calculation gain, or UP factor is multiplied handles the UP factor differently and can calculate
to the actual calculated load. From the example shown different loads for the same haul cycle. For these
in Figure XX, the calculated load is 143.8 tons. If the reason it is recommended that the payload meter
UP factor is set to +5% the displayed load will be 143.8 be set to use PL:00 in all cases.
x 1.05 = 151 tons. This factor can be used to minimize
the effects of systematic error for a particular truck. The PL:00
UP factor is not applied uniformly to all load calcula-
tions. There are three operating modes for the payload Modular Mining Transmission - The data is captured
meter and the UP factor is applied differently to each at the last transition from 0 to 1 MPH prior to traveling
mode. Therefore, it is recommended that this percent- 160 meters from the shovel. The captured data is
age be set to 0. There are significant differences in final transmitted when the truck travels 160m from the
calculated load that can be introduced by adjusting this shovel. This load calculation will use the UP factor
gain. percentage.
Payload meters sent from the factory are typically set Memory Storage - Same as above, the data is cap -
to "UP: 5" indicating a +5% gain in final load. tured at the last transition from 0 to 1 MPH prior to
traveling 160 meters from the shovel. The captured
This should be checked on all new meters and data is stored into memory when the body rises at the
changed to "UP: 0". dump. This load calculation will use the UP factor
percentage.
PL Mode - Load Calculation Timing
PL:01
Load Calculation Timing
Modular Mining Transmission - The data is captured
The PL mode controls when the payload meter takes at the last transition from 0 to 1 MPH prior to traveling
a sample of the data and calculates the load. There 160 meters from the shovel. The captured data is
are three modes available. There are two sets of data transmitted when the truck travels 160m from the
that are affected by the PL mode setting. shovel. This load calculation will use the UP factor
percentage.
• Modular Mining Transmission
Memory Storage - The data is captured and stored
• Memory Storage when the body rises from the frame. This calculation
will not use the UP factor percentage.
PL:10
The PL mode setting can have a significant impact on Modular Mining Transmission - The data is captured
the perceived accuracy of the payload meter. and transmitted when the truck travels 160 meters
from the shovel. This calculation will not use the UP
PL:00 is the only recommended setting. factor percentage.
Use of settings other than PL:00 Memory Storage - The data is captured and stored
is NOT recommended. when the body rises from the frame. This calculation
will not use the UP factor percentage.

FINAL GEAR RATIO SELECTION
For an 830E truck, the proper gear ratio has to be
selected.
1. Press and hold the MODE and LIGHT/INC
switches until “CHEC” is displayed.
2. Press and hold the TOTAL/SFT and LIGHT/INC

switches until “S.SEL
is displayed.
3. Press the CAL/CLR switch repeatedly

until “A.XX” is displayed, where
“XX” is one of the following:
“XX” Gear Ratio Remarks

00 31.875 Original
01 36.400 High Traction
02 28.125 Standard
03 26.625 High Speed
NOTE: The Payload Meter is originally set to “00".
4. Press the TOTAL/SFT switch and "XX" will flash.

5. Press theLIGHT/INC switch to select the desired
gear ratio.
6. Press the MODE switch
and "CHEC" will be displayed.
7. Press the MODE switch and the meter will return

to normal operation.

BATTERY REPLACEMENT PROCEDURE 4. Remove the electrical connector. Remove the
ERROR CODE, F-09, DISPLAYED screws on the top surface and the rear face.
Remove the cover (Figure 20-8). This will expose
Replacing the Battery the battery, its wires, and the connector.
The payload meter has an internal battery used to

protect the memory from being erased when the key
switch is turned to the OFF position. Battery life is
approximately 2 years. The capacity of the battery is
monitored by the payload meter. When the voltage of
the memory battery does drop, error code, F-09, will
be displayed.
When the F-09 error code appears, download the data
within 48 hours; otherwise, the data may be lost. The
Haul Cycle data may not be recorded properly while
F-09 is displayed.
At this time it will be necessary to replace the battery.
This should be performed when the truck is in an
unloaded condition. The data stored in the payload FIGURE 20-8. ACCESS TO BATTERY
meter should be downloaded to a personal computer
or carry out the memory card dump operation. If this is 5. Grasp the wires coming from the battery and pull
not done, when the battery is disconnected all data will out. By pulling perpendicular from the board, it will
be lost. disconnect the connector from the board and pull
All that is required is a phillips-head screwdriver and a the battery out of its holder all at the same time
new battery (P/N 581-86-55710) (Figure 20-9).
1. Keyswitch in the ON position, download the data

stored in the payload memory, or carry out the
memory card dump operation.
2. Turn the keyswitch to the OFF position.
3. Remove the four mounting screws holding the
payload meter in position and then pull the pay-
load meter out, away from the instrument panel
(Figure 20-7).
NOTICE - Be careful not to let dirt, metal or spare parts
to drop inside the controller at any time.
FIGURE 20-9. BATTERY INSTALLATION
6. Insert the connector of the new battery directly into

the connector on the board (Figure 20-10). Place
the battery in the battery holder, and pass the
wiring through the notch. When doing this, insert
the wiring into the bottom of the holder and pass
it through the notch.
FIGURE 20-7. REMOVING PAYLOAD METER 7. Install the controller cover, replace the electrical
connector, and install the payload meter control-
ler back into the instrument panel.

9. Forcibly clear the data for the total payload and
overall number of cycles.
With this operation performed, all the unwanted
data inside the payload meter is cleared. Except
for the calibration data, all the data recorded in
the previous steps is also erased.
10. After this procedure has been performed the
system is ready for normal function.
SUSPENSION PRESSURE SENSOR

The pressure sensors are mounted on top of each
suspension. The sensors produce a voltage signal
FIGURE 20-10. BATTERY CONNECTION from 1 – 5 volts output.
The pressure sensor is mounted to the suspension
After Replacing the Battery
cylinder using a Schrader Valve assembly, adapter
While replacing the battery, the backup power source and sensor. The sensor can be replaced without re -
for the memory inside the payload meter is momentar- leasing the pressure in the suspension by removing
ily disconnected. the sensor with the adapter.
This can allow unwanted data (garbage) to enter the
memory and affect the meter’s recognition proce - Removal
dures. The following will remove this unwanted data.
1. Turn the keyswitch to the ON position.
may flash. Make certain the adapter and sensor are removed
together from the valve assembly. Removing the
complete valve assembly or just the sensor may
2. Using the Operator Check Mode, set the speed result in the component being forced out of the
limit option code, time and date. (These were suspension by the gas pressure inside.
erased from memory when the battery was dis-
connected). 1. Disconnect sensor from truck wiring harness.
Note: The Schrader valve in the valve assembly
3. Without turning the keyswitch to the OFF position
will prevent gas from escaping when adapter
advance to the start position. With the engine
and sensor are removed together. If entire
running, the display: may flash.
valve assembly is turned allowing nitrogen gas to
escape, recharging of the suspension will be
required.
4. Perform the Calibration procedure.
Refer to Page 15. 2. Hold valve (2, Figure 20-11) with wrench while
removing the adapter/sensor assembly (3 & 4).
5. Load the truck to the rated payload, or close to it.
Dump the load. 3. Remove sensor (4) from adapter (3).
6. Move the truck to a safe area, wait at least 5
seconds after dumping the load, then shut the
truck down.
7. Turn the keyswitch back to the ON position but do
not start the engine.
8. Perform the Data All Clear in the Operator Check
mode.
FIGURE 20-11. PRESSURE SENSOR.

1. Schrader Valve 3. Adapter
2. Valve Assembly 4. Sensor

Installation Installation
1. Install new O-ring on sensor (4, Figure 20-11) and 1. Install inclinometer (3, Figure 20-13) with cap -
install sensor into adapter (3). Tighten sensor to screws, nuts and lockwashers (4).
22–29 ft.lbs. (30–39 N.m) torque.
2. Install new O-ring on adapter (3) and install com-
plete adapter/sensor assembly into valve (2).
Hold valve body and tighten adapter/sensor as-
sembly to 103 ft.lbs. (176 N.m) torque.
3. Connect sensor wiring to truck wiring harness.
The sensors have three wires. Be sure that wires
are connected correctly. (Figure 20-12)
FIGURE 20-13. INCLINOMETER

FIGURE 20-12. SENSOR SIDE CONNECTOR VIEW 1. Operator’s Center 3. Inclinometer
Console Frame 4. Capscrew, Nut and
Pin Number Wire Color Wire Function 2. Bracket Lockwasher
1 Black Ground (GND)
2 Red + Power 2. Connect inclinometer wiring to the truck wiring
3 White Signal harness. (Figure 20-14)
Be sure that wires are connected correctly.
INCLINOMETER
As the truck is tilted fore or aft, the weight distribution
between the front and rear axles changes. To compen- FIGURE 20-14. INCLINOMETER SIDE
sate for this, the inclinometer measures the ground CONNECTOR VIEW
angle at which the truck rests. This data is then sent
to the payload meter so it can calculate the correct Pin Number Wire Color Wire Function
payload weight. The inclinometer is located below the
operator’s center console (passenger seat structure). 1 Black Ground (GND)
2 White Signal
Removal 3 Red + Power
1. Disconnect inclinometer wire lead from harness.
Adjustment
2. Remove the three capscrews, nuts and lockwash-
ers (4, Figure 20-13) and inclinometer (3). 1. Park the truck on a 0% grade.
2. Loosen the three Inclinometer mounting cap -
screws (4, Figure 20-13) and rotate the Incli -
nometer until a voltage range of 2.6 ±0.1 Volts
can be measured (using aVolt/Ohm Meter) at pins
1 and 2 of the inclinometer electrical harness
connector.
3. Tighten all capscrews (4, Figure 20-13) to stand-
ard torque, after adjustment.

SCOREBOARD
Description
The Scoreboard from Komatsu Mining Systems uses
information from the Payload Meter to display the
current load. It uses ultra-high-brightness LED tech -
nology to form 3 digits. The sign is fully sunlight read-
able and housed in a rugged steel enclosure.
The Scoreboard displays each swing pass as the truck
is being loaded. As the truck drives away, the sign will
display the last swing pass until the final load calcula-
tion is made. It will then switch to display the final load
calculation and hold it until the truck dumps. The sign
will then clear for the empty ride back to the shovel.
Making Connections
The Scoreboard connects to the RS232 port on the
Payload Meter. It must share this connection with other
dispatch systems like Modular Mining as well as the
PC download connection. This sharing of the single
port creates special circumstances when using a Per- Figure 20-15. Scoreboard
sonal Computer or dispatch system.
The Scoreboard is in constant communications with
The harness for the Scoreboard supplies two extra
the Payload Meter and must acknowledge every mes-
connections in the overhead compartment of the cab.
sage from the meter. In addition, the Scoreboard must
One is for the existing PC port and the other is for
also signal the Payload Meter that it is ready to receive
Modular Mining.
messages by supplying a 5vdc signal over the CTS
line. Installations that include Modular Mining or other When two Scoreboards are installed, the first sign
dispatch systems must take over the responsibility for transmits load information and power to the second
acknowledging messages from the Payload Meter. To sign. Note that the communications wire from the first
do this, the return communications line and the CTS sign connects to terminal 35L7. This is the retransmit
line from the Scoreboard must be cut and taped back. terminal. This wire then connects to the 35L4 terminal
When this is done, the Scoreboard simply monitors in the second sign. This is the receive terminal of the
communications between the Payload Meter and second sign.
Modular Mining. The Modular Mining system acknow-
The Payload Meter must be set to use OP12. Refer
ledges each message from the meter.
to "Setting the Option Code" for instructions.
Sharing this RS232 port with the Personal Computer
Once in this mode, the Payload Meter will look for the
for downloading can also create problems with com -
Scoreboard and attempt to communicate with it. If
munications. The Payload Meter can confuse mes -
there are communications problems the Payload Me-
sages from the PersonalComputer and Scoreboard.
ter may indicate a communications port error. Refer to
To eliminate this problem, the Scoreboard must be
"Fault Codes" for additional information.
turned off during downloading of the Payload Me-
ter. Using the circuit breaker to turn off the main power
to the Scoreboard is the best way to accomplish this.
The power to the Scoreboard must be turned off before
communications between a Personal Computer and
the Payload Meter can start. Once the download proc-
ess is finished, the power needs to be restored to the
Scoreboard to keep from receiving F99 or F93 error
codes.

Normal Operation of the Scoreboard
On power up, the Scoreboard will display "888" and
then display the current software version, "10". The
sign will then go blank until the Payload Meter begins
sending load information. There is also a small light
that blinks once per second in the center of the top
portion of the last digit that is visible by close inspec -
tion. This light indicates that the sign is powered and
operating normally.
During the typical loading cycle there is a short delay
from when a bucket load of material is dumped into the
body and when the Scoreboard indicates the weight.
This delay is caused by the Payload Meter waiting for
the oscillations in the suspensions to settle out before
calculating a current load. The Scoreboard will display
the current load calculated by the Payload Meter after
each swingload.
If the truck operator releases the brake lock and begins
to drive before the last swingload calculation is made,
the Scoreboard will never display the last swingload.
The Scoreboard will display the last load calculation
made during the loading process until the final load
calculation is made approximately 160 meters from the
shovel. At this point the final load will be displayed.
This number will remain until the truck dumps the load.
There will typically be a difference between the last
swingload and final load calculations.
PAYLOAD METER BACK PANEL

CONNECTIONS
CN1 - AMP MIC-MKII 13 Pins White Connector CN3 - AMP MIC-MKII 9 Pins
No. Description Comments White (RS-232C Port)
1 Power +24V (Battery) No. Description

2 Lamp Relay 1 1 RTS
3 Lamp Relay 2 2 SG
4 Lamp Relay 3 3 RD
5 Lamp Relay 4 4 TX
6 Lamp Relay 5 5 CTS
7 Speed Sensor (Signal) 6 DTR
8 Speed Sensor (GND) 7 DSR
Running - 28VDC 8
9 Alternator R Terminal (Charge Signal)
Off - 0VDC
10 Key Switch ACC Terminal (ACC Signal)
11
12
13 GND (Power GND)
CN2 - AMP 040 12 Pins Black Connector CN4 - AMP 040 8 Pins Black
No. Description Comments (Optional Input, Reserved)
Running Open No. Description

1 Engine Oil Pressure Switch
Off - Closed 1 Optional Input GND
2 Sensor Power Out +18V 2 Analog Input 1
3 Sensor GND 3 Analog Input 2
4 Left FrontSuspension Pressure Sensor 1-5VDC Normal 4 Digital Input 1
Right Front Suspension PressureSensor 5 Digital Input 2
5 1-5VDC Normal
6
6 Left Rear Suspension Pressure Sensor 1-5VDC Normal 7
7 Right Rear Suspension Pressure Sensor 1-5VDC Normal
8 Inclinometer
Body Down - Open
9 Body Rise Signal
Body Up - Gnd
Lock Off - Open
10 Break Lock Signal/Neutral Signal
Lock On - Gnd
11
12

PAYLOAD CIRCUIT NUMBERS
Circuit Designation Circuit Description

39F, 39F1...39F5 +18 volt sensor power supply
39F Pressure signal Right Rear
39F Pressure signal Left Rear
39FC Pressure signal Right Front
39FD Pressure signal Left Front
39F Inclinometer signal
39FG Sensor ground
39A PLM lamp output - green
39B PLM lamp output - amber
39C PLM lamp output - red
39D PLM lamp output - unused
39E PLM lamp output - unused
39G +24 volt PLM power
39AA Load light - green
39BA Load light - amber
39CA Load light - red
73FSL TCI 100% load signal - 930E only
73MSL TCI 70% load signal - 930E only
714 Speed signal
714AT Speed signal
63L Body up (gnd = up, open = down)
39H Brake lock (gnd = release, open = lock)
35L1 PLM RS232 RTS (request to send)
35L2 PLM RS232 signal ground
35L3 PLM RS232 receive
35L4 PLM RS232 transmit
35L5 PLM RS232 CTS (clear to send)
35L6
35L7/35L4 Scoreboard 1 to scoreboard 2
35L8 PLM chan 2 TxD
35L9 PLM chan 2 RxD
21C Engine oil pressure (gnd = off, open = run)
21D Alternator R-Terminal (open = off,+24V = run)

PAYLOAD METER II RE-INITIALIZATION PROCEDURE
This procedure is designed to reset the Payload Meter II to clear repeated F.CAL errors.
This procedure is necessary to fix a rare condition in 7. Set the time, date, OP, PL, and UP settings. All
the operation of the meter. Indication for this procedure other user settings should updated at this time.
is a repeated display of F.CAL on the meter despite
8. Calibrate the Payload Meter by holding the CAL
repeated calibration. If possible, download the Pay -
button until CAL flashes.
load Meter before performing this procedure. This
procedure will erase all memory and user settings. 9. Release the Brake Lock (Park Brake for 330M)
and begin driving 5-8 MPH on level ground and
NOTE:
press CAL.
This procedure should be performed before any
CAL should display until the meter finishes its
Payload Meter is returned for warranty or repair.
calibration.
10. Load the truck to rated load and drive through one
Before performing this procedure, be sure that the
haul cycle.
engine inputs into the payload meter can be manipu-
lated to indicate engine running and engine stopped. 11. After dumping the load, wait at least 15 seconds
Some payload meter installations have hard-wired and drive the truck to a safe location.
these inputs. These inputs must be accessible and
12. Stop the truck and shut down the engine.
able to produce the following input conditions:
13. Turn on the Payload Meter but leave the engine
off.
21C 21D
14. Hold MODE and LIGHT until CHEC flashes.
Condition Engine Oil Alternator "R"
Pressure Terminal 15. Hold LIGHT and CAL until A:CLE flashes.
Engine Running Open 24VDC 16. Press CAL to clear the service memory.
Engine Stopped Ground Open
17. When CHEC is displayed, press MODE to return
to normal operation.
1. Turn off all systems. 18. Clear the Haul Cycle Memory by holding MODE
until Cd:dP is displayed.
2. Turn on the Payload Meter but leave the engine
off. 19. Press MODE and A.CLE will be displayed.
3. Hold MODE and LIGHT until CHEC flashes. 20. Hold CAL until A.CLE flashed.
4. Hold the CAL, TOTAL and LIGHT buttons until 21. Press CAL once more to clear the haul cycle
00:00 is displayed. memory.
5. Pres CAL for 2 seconds. 00 00 will flash and the 22. Clear the operator load counter by pressing the
meter will erase its memory and reset to its factory TOTAL button until ":" is displayed.
settings. This includes and OP, UP, PL, P.SEL,
23. Hold the CAL button until the display flashes.
and E.SEL settings.
The meter will restart and display F.CAL. 24. Hold the CAL button until 0000 is displayed to
clear the memory.
6. Start the engine.
25. The payload meter should now function normally.

NOTES
PORTIONS OF THIS PRODUCT RELATING TO PAYLOAD MEASURING SYSTEMS ARE

MANUFACTURED UNDER LICENSE FROM
L. G. HAGENBUCH holder of
U.S. Patent Numbers 4,831,539 and 4,839,835

SECTION N
OPERATOR’S CAB
INDEX
TRUCK CAB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N2-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N2-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N2-1
CAB COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N3-1

WINDSHIELD WIPER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N3-1
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N3-1
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N3-1
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N3-1
WINDSHIELD WASHER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N3-2
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N3-2
AIR CLEANER INDICATOR GAUGE . . . . . . . . . . . . . . . . . . . . . . . . . . . N3-3
OPERATOR COMFORT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-1

OPERATOR SEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-1
Adjustment Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-1
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-2
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-2
DASH PANEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-3
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-3
HEATER/AIR CONDITIONER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-3
Heater/Air Conditioner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-3
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-3
Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-4
Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-4
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-4
HEATER CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-4
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-4
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-4
OPERATOR CAB AND CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-1

OPERATOR CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-1
Retarder Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-2
Center Console . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-3
Engine Electronic Control System . . . . . . . . . . . . . . . . . . . . . . . . . . N5-6
Hoist Control Lever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-8
Dump Body Control Linkage . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-10
Steering Column Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-11
N01019 Index N1-1

SECTION N OPERATOR’S CAB INDEX (CONT’D)
OPERATOR CAB AND CONTROLS (CONT’D)

INSTRUMENT PANEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-13
INSTRUMENT PANEL (Upper Half) . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-15
INSTRUMENT PANEL (Lower Half) . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-18
HEATER/AIR CONDITIONER CONTROL . . . . . . . . . . . . . . . . . . . . . . . N5-23
N1-2 Index N01019

TRUCK CAB
1. Disconnect the ground wire between the negativ 1. Lower cab and deck section onto truck and align
terminal of the batteries and the frame. capscrew mounting holes. Remove lifting device.
2. Remove capscrews (2, Figure 2-1) and washers 2. Adjust left hand deck rubber mounts;
from each corner of the left deck section. a. Temporarily assemble the mounting parts with-
3. Disconnect all electrical wiring, air lines, and hy - out shims.
draulic lines that would interfer with the removal b. Measure dimension "a" (Figure 2-1) at four (4)
of the cab deck. places on each mounting pad as shown.
4. Attach lifting device with wood blocks (5, Figur c. Add shims to the side where dimension "a" is
2-2) and lift deck section up and away from truck. largest, and adjust so that the difference b -
tween dimension "a" at the four places is within
5. Mark shims (4) so they will be installed in the sam 0.5 mm (0.02 in.).
location when the cab and deck are installed.
3. Tighten nuts to 35-43.5 kg.m (254-315 ft.lbs.
torque.
FIGURE 2-1. RUBBER MOUNTING PADS (LEFT

DECK)
1. Cover 5. Rubber Mounting FIGURE 2-2. CAB AND DECK

2. Capscre 6. Flatwashe
3. Special Washer 7. Nut 1. Cab 4. Door
4. Shims 2. Strap 5. Wood Block
3. Lifting Device
N02008 Cab N2-1

NOTES
N2-2 Cab N02008

CAB COMPONENTS
FIGURE 3-1. WINDSHIELD WIPER AND MOTOR INSTALLATION

1. Motor, Wiper 4. Nozzle 7. Grommet 10. Washer, Spring
2. Arm, Wiper 5. Hose 8. Grommet 11. Washer
3. Blade 6. Clip 9. Screw
WINDSHIELD WIPER /WASHER Removal

The wind shield wip ers are ac t ivat ed b y the 1. Disconnect wiper motor wire harness near th
wiper/washer switch on the steering column. The wiper motor under the dash.
switch has four wiper position settings and a washer
2. Remove wiper arm (2, Figure 3-1) cover and nut
push-button:
from shaft.
a. INT: Wipers operate intermittently.
3. Remove four screws (9) and remove the wiper
b. OFF: Wipers are off. mortor assembly (1).
c. LOW: Wipers operate at low speed.
d. HI: Wipers operate at high speed.
Installation
1. Install the wiper mortor assembly (1, Figure 3-1)
For Washer Spray, press end of switch to spra
with the four screws (9).
washer liquid onto windshield.
N03007 Cab Components N3-1

FIGURE 3-2. WINDSHIELD WASHER ASSEMBLY
1. Tank 3. Bolt 5. Bolt 7. Clip

2. Bracket 4. Washer 6. Washer
2. Install nut, cover and wiper arm (2).

3. Connect wiper motor wire harness.
Service
If windshield washer maintenance is required, check
the following;
WINDSHIELD WASHER
1. Obstructions in the inlet to the pump.
Operation 2. Kinked supply hose to the nozzle.
The windshield washer has a 3.8 l (1 gal) plastic con - 3. Check for system voltage at the pump terminals.
tainer with an external 24 volt electric pump. The If voltage is not OK, check the wire harness or th
washer is controlled by pushing in on the windshield wiper switch. If the voltage is OK at the pump,
wiper knob. The switch automatically returns to the off replace the entire pump assembly.
position when it is released. When the switch is acti -
vated, washing solution is fed to a nozzle located in the
front wall of the cab below the windshield.
N3-2 Cab Components N03007

AIR CLEANER INDICATOR GAUGE
The air cleaner indicator is mounted between the air
filters and can be seen from the operators seat.
The air cleaner indicator is factory calibrated and pr -
set to show a red signal when there is a specific amount
of restriction in the engine air intake system. The re
indicator remains locked in view even with the engin
shut down. After servicing the air cleaner, press th
reset button to remove the red signal.
N03007 Cab Components N3-3

NOTES
N3-4 Cab Components N03007

OPERATOR COMFORT
OPERATOR SEAT
The operator’s seat is fully adjustable for the driver’s
comfot and ease of operation. The seat is inde -
pendently mounted from the cab for easy maintenance
and repair.
Adjustments must be made while sitting in the
seat:
1. Weight Adjustment Knob:
Pull crank handle out of knob (1, Figure 4-1) and
hold crank down, turning crank clockwise de -
creases cushioning effort of seat and turning
counterclockwise increases cushioning effect.
The weight adjustment knob range of operation
is 19.5 - 20.5 turns. Release crank handle and
fold handle to stow position.
2. Thigh Adjustment Knob:
The thigh adjustment (2) has two positions: First
position is horizontal; Second position is one turn
of knob and front section of seat rises approxi -
mately 15o. Turn knob in reverse direction to
return seat to horizontal position.
3. To adjust the Forward-Backward location of seat:
Move lever (3) out to the left. Slide the seat
foreward or backward as desired to the best
position. Then release lever. Seat will lock and
remain in this position. FIGURE 4-1 OPERATOR SEAT
4. Back Tilt Control Lever 1. Weight Adjustment Knob
2. Thigh Adjustment Knob
Pull up lever (4). Move seat backrest to the angle
3. Forward-Backward Adjustment Lever
position desired and release lever.
4. Back Tilt Control Lever
5. Lumbar Support Adjustment Control: 5. Lumbar Support Adjustment Control
Turn lumbar control knob (5) one turn. This will
move lumbar cushion to the out setting, providing
added support to the lower back. Turning the
knob in the reverse direction will return the seat
to normal position.
N04014 Operator Comfort N4-1

FIGURE 4-2. OPERATOR’S SEAT INSTALLATION
1. Operator’s Seat 4. Washer
2. Seat Belt 5. Tether Belt
3. Bolt
Removal
Installation
1. Remove four bolts (3, Figure 4-2).
1. Install seat in cab.
2. Remove seat assembly (1) from cab.
2. Install and tighten bolts (3) to standard torque.
N4-2 Operator Comfort N04014

DASH PANEL 6. Remove four capscrews retaining the left access
door (where the recirculation filter is located) in
Removal place.
7. Disconnect the two air conditioner lines at the
core.
1. Remove the four tapered screws from the warning
light bracket. 8. Remove control cable from coolant control valve.
2. Remove the four screws and the sun shade from 9. Remove two capscrews holding the mounting
above the instrument panel display. brackets to the cab floor.
3. Remove the five screws retaining the instrument 10. Disconnect the two heater coolant hoses.
panel display.
11. Slide heater/air conditioner unit out. While sliding,
4. Remove the eighteen screws holding the plastic disconnect wiring harness from blower motor,
dash in place and the four heater/air conditioner blower motor resistor and air conditioner sensor.
knobs.
5. Remove dash panel.
Installation
1. Slide heater/air conditioner unit in at the same
time with the access door on the left side. While
Installation sliding unit in, connect wiring harness to blower
motor, blower motor resistor and air conditioner
1. Install dash panel. sensor.
2. Install the eighteen screws holding the plastic 2. Connect the two heater coolant hoses.
dash in place and the four heater/air conditioner
knobs. 3. Install two capscrews holding the mounting brack-
ets to the cab floor.
3. Install the five screws retaining the instrument
panel display. 4. Install control cable to coolant control valve. Ad -
just to ensure it travels to complete on and off
4. Install the four screws and the sun shade from positions.
above the instrument panel display.
5. Connect the two air conditioner lines to the core.
5. Install the four tapered screws from the warning
light bracket. 6. Install four capscrews to hold the left access door
(where the recirculation filter is located) in place.
7. Connect the two air conditioner water drain hoses
to the air conditioner assembly.
HEATER AND AIR CONDITIONER UNIT
8. Install the four capscrews and the steel blower
Removal cover to the right side of the heater assembly
1. Drain engine cooling system slightly to avoid 9. Install the heater/air conditioner cover in front of
coolant loss when removing heater assembly the passenger seat by installing the four corner
from cab. capscrews.
2. Discharge air conditioner system of refrigerant. 10. Fill the engine cooling system with the coolant that
3. Remove the heater/air conditioner cover in front was drained in Step 1 during removal.
of the passenger seat by removing the four corner 11. Charge the air conditioner system.
capscrews.
4. Remove the four capscrews and the steel blower
cover from the right side of the heater assembly
5. Disconnect the two air conditioner water drain
hoses from below air conditioner assembly.
N04014 Operator Comfort N4-3

HEATER AND AIR CONDITIONER CORE Installation
REPLACEMENT 1. Connect the cables to the vent and the defrost
levers.
Disassembly
2. Connect air conditioner switch and illumination
1. Split the assembly by removing ten screws (eight light wire at connectors.
at the split and two on top).
3. Connect blower speed switch wiring at connector.
2. Remove motor by removing three screws.
4. Slide control panel in and install the two screws
3. Remove resistor by removing two screws. holding the rear support to control plate.
4. Remove heater core by disconnecting the water 5. Slide control panel in part way and connect cable
pipes and lifting it out of the housing. to fresh/recirculate lever.
5. Remove air conditioning core by removing tube 6. Install two top screws holding the rear reinforce -
support screw and lifting the core out of the ment in place.
housing.
7. Install the four front screws.
8. Install steel cover above the heater controls.
Assembly 9. Install the top dash cover and metal warning light
1. Install air conditioning core and tube support holder.
screw in the housing.
2. Install heater core and connect the water pipes.
3. Install resistor with two screws.
4. Install motor with three screws.
5. Join the two halves with ten screws (eight at the
split and two on top).
DASH LEVER CONTROLS

Removal
1. Remove top dash cover and metal light holder.
2. Remove steel cover above the heater controls.
3. Remove the four front screws.
4. Remove two top screws holding the rear reinforce-
ment in place.
5. Slide control panel out part way and disconnect
cable from fresh/recirculate lever.
6. Slide control panel out further and remove the two
screws holding the rear support to control plate.
7. Disconnect blower speed switch wiring at connec-
tor.
8. Disconnect air conditioner switch and illumination
light wire at connectors.
9. Disconnect the cables from the vent and the
defrost levers.
N4-4 Operator Comfort N04014

OPERATOR CAB AND CONTROLS
FIGURE 5-1. STEERING WHEEL AND CONTROLS

1. Steering Wheel 5. Windshield Wiper/Washer Switch 9. Throttle Pedal
2. Tilt Lever 6. Headlight Dimmer Switch 10. Center Console
3. Turn Signals and Headlight Switch 7. Retard Control Lever 11. Differential Lock Pedal (Optional)
4. Air Horn 8. Brake Pedal 12. Hoist Control Lever (Dump Lever)
13. Retarding Capacity Decal
(1) Steering Wheel And Controls (2) Tilt Lever

The steering wheel (1, Figure 5-1) may be adjusted Adjust the tilt angle of the steer-
through a tilt angle to provide a comfortable position ing wheel by pulling Tilt Lever (2)
for the operator. For service information, refer to up, toward steering wheel and
"Steering Column Service" later in this chapter. moving the wheel to the desired
angle. The steering wheel may
also be adjusted (telescoped)
“In” or “Out” at this time. Pushing
the lever back locks the wheel in the desired position.
N05030 11/98 Operator Controls and Instrument Panel N5-1

(3) Turn Signal Lever Switch (7) Retard Control Lever
Turn Signal Lever (3) is
The retarder control lever
used to activate turn signal
(7) allows the operator to
lights:
apply only the REAR oil-
Move lever upward to sig-
cooled brakes.
nal a turn to the right (R).
Move lever downward to During normal operation,
signal a turn to the left (L). the retarder control lever
should be used to control
the speed of the truck and
to stop the truck instead of using the foot-operated
(4) Horn
service brake pedal. Use of this lever allows the op-
erator to apply the REAR oil-cooled brakes only ,
The horn (4) is actuated by the
thus extending the life of the front caliper disc pads
horn button in the center of the
while still maintaining maximum control of the truck.
steering wheel. When the but-
The foot-operated brake pedal should be used when
ton is depressed, it activates
maneuvering in tight places, at the shovel and dump,
the horn solenoid.
and when quick stops or severe braking is required.
Before starting down a grade, maintain a speed that
will insure safe driving and provide effective retarding
under all conditions.
(5) Windshield Wiper / Washer Switch
Refer to the "Retarding Capacity" decal (13, Figure
Windshield Wiper Switch (5) is
5-1, & shown below) which is applied to the upper
used to activate the wiper
left-hand corner of the cab windshield. This decal is
blades and washer system.
designed to help the operator maintain a safe vehicle
This switch has four wiper po-
speed while descending a grade with a loaded truck.
sition settings and a washer
push-button:
a. INT: Wipers operate intermittently.

b. OFF: Wipers are off.
c. LOW: Wipers operate at low speed.
d. HI: Wipers operate at high speed.
e. Press end of switch to spray washer liquid onto
windshield.
(6) Headlights and Dimmer Switch

The headlights and dimmer switch (6, Figure 5-1) is
part of the turn signal lever function.
The headlights are turned
“Off” and “On” by rotating
the switch on the end of
the lever handle. The
switch has three positions:
OFF; Running/Clearance
lights; and Headlights.
The dimmer switch is part
of the turn signal leve
function.
Pulling the lever up will activate headlights to low beam

[A]. Pushing the lever down activates headlights to
high beam [B].
N5-2 Operator Controls and Instrument Panel N05030 11/98

Retarder Operation (9) Throttle Pedal
For efficient retarder operation, the operator should:
The Throttle Pedal (9) is a foot
• Preselect a ground speed and gear range for a operated treadle pedal which al -
known grade that will permit continous retarder lows the operator to control fuel to
operation within the LIMITS OF THE CHART. the engine to provide engine ac -
celeration.
• Maintain engine RPM between 1800 — 2400
RPM, and
The electronic treadle pedal sends signals to the elec-
• Observe the Brake Oil Temperature gauge to tronic engine fuel control system. The movement of the
make certain the Brake Oil Temperature does not governor control arm corresponds directly to travel of
exceed 248°F (120°C). the treadle pedal as applied by the operator. When the
pedal is released, a spring returns the pedal and
If the Brake Oil Temperature exceeds this limit, move
governor control arm to the low idle position.
the transmission range selector lever to a lower gear
and use the foot-operated service brakes to reduce the
truck ground speed. This will allow the transmission to
shift to the next lower gear range for more efficient
cooling.
(10) Center Console
If the Brake Oil Temperature continues to exceed
248°F (120°C), select a safe area out of the way of The Center Console (10, Figure 5-1) is located to the
other traffic, stop the truck, move the transmission right of the Operator.
range selector lever to the Neutral (N) position, and
operate the engine at approximately 1200 RPM until
the Brake Oil Temperature gauge registers in the Transmission Range Selector (1, Figure 5-2)
"green" range.
The Transmission Range Selector has seven positions
For better control under dry road conditions, the op- (R, N, D, 5, 4, 3, and L).
tional front wheel brakes may be turned on.
NOTE: For information to service the Retarder Control
Valve, refer to "Retarder Control Valve" in the Air
System, Section "K", of this manual .
When operating the shift lever, be sure to set it in
position securely (detent). If the lever is not in a
detent position, the shift position display on the
(8) Brake Pedal panel may go out and the transmission warning
monitor lamp may light up.
The Brake Pedal (8) is a
foot-operated pedal which When shifting between FORWARD and REVERSE,
activates air-over-hydrau- stop the machine completely, and reduce engine
lic pressure converters speed to low idle when moving the lever.
which apply front caliper If the parking brake is not released, and the shift
dry disc brakes and rear lever is moved to a position other than N, the
oil-cooled wet disc brakes. central warning lamp will flash and the alarm buzz-
This pedal should be used when maneuvering in tight er will sound.
places, at the shovel and dump, and when quick stops
or severe braking is required. If the dump lever is not at the FLOAT position, and
the shift lever is moved to a position other than N,
the central warning lamp will light up and the alarm
buzzer will sound.
Do not move the shift lever with the accelerator
pedal depressed. This will cause “shift shock”,
and will reduce the life of drive train components.

Release Button When moving the range selector lever from “N” to “R”,
or from “D” to 5, the Release Button on the end of the
handle (operator side) must be pressed before the
selector lever can be moved.
“R” - REVERSE position -

Bring truck to a complete stop before shifting from
DRIVE to REVERSE or vice-versa. The Reverse
Warning Horn is activated when REVERSE position is
selected.
“N” - NEUTRAL position -

is used when starting the engine, during loading op-
erations and parking the truck with engine running.
The truck cannot be started unless the range selector
is in the “N” - NEUTRAL position.
“D” - DRIVE position -

When starting from a stopped position, the transmis-
sion will shift automatically to second gear. As the truck
ground speed increases, the transmission will auto -
matically upshift through each gear to seventh gear
operation. As the truck ground speed slows down, the
transmission will automatically downshift to the correct
gear for grade/load/engine conditions.
NOTE: The transmission will be locked into second
FIGURE 5-2. CENTER CONSOLE gear if the body is not seated on the frame.
1. Transmission Range Selector (Shift Lever) Always lower the body when traveling.
2. Shift Limiter Switch
3. Power Mode Selector Switch
4. Emergency Steering Switch “5, 4, 3" positions -
5. Emergency Brake Lever Road and load conditions sometimes make it desirable
6. Parking Brake Valve Lever to limit the automatic up-shifting to a lower range.
7. Engine Shutdown Warning Light These positions provide more effective retarding on
8. Engine Maintenance Light grades.
9. Engine Maintenance Light When the range selector is placed in any one of these
10. PMC Display (Optional) positions, the transmission will not shift above the
11. Engine Fault Code Switch highest gear range selected.
12. Engine Diagnostic Switch It will also downshift to first range when required by
grade/load/engine conditions.
When conditions permit, select position “D” for normal
operation.
“L” - LOW position - Use this range position when

maneuvering in tight spaces and when pulling through
mud or deep snow. Use this range position also when
driving up and down steep grades where maximum
driving power or maximum retarding is required.
NOTE: The transmission will be locked into first gear
if the body is not seated on the frame.
Always lower the body when traveling.

Shift Limiter Switch (2, Figure 5-2) Emergency Steering Switch (4, Figure 5-2)
This switch is used to limit the highest speed range This switch (4) actuates the
when the transmission shift lever is in “D” or “L emergency steering pump.
Ranges.
Position:
Depress the center button
“D” Range - F2 - F7 to activate the emergency
“L” Range - F1 - F2 steering pump motor.
“D” Range - F2 - F6
Depress the button again to turn
“L” Range - F1
OFF the emergency steering.
When the switch is “On”, the RED
When the switch position is “out” the light is “off”. lamp in the switch will light. The red
When the switch position is “in” the light is “on”. warning light on the right-hand side
of the instrument panel will also
light.
Economy / Power Mode Switch (3, Figure 5-2)
This switch activates a part of the

electronically controlled engine fuel
system. Do not use the emergency steering for longer than
The switch controls optimum oper- 90 second intervals and do not drive in excess of
ating efficiency in loaded vs. un - 5 km/hr. (3 mph).
loaded conditions. Use this operation only in emergency situations.
Do not use this function for normal body opera-
Normal Idle - When in “Economy Mode tion.
(in/light on), fuel usage is reduced as full
engine power is not required.
When the emergency steering is actuated, it is possi-
ble to use the dump lever to raise the dump body.
Advanced Idle - When switched to
However, the body cannot be raised when loaded.
“Power Mode” (out/light off), full fuel flow
is allowed to provide maximum rated Emergency steering will be activated automatically if
engine power. the steering pump fails or the engine stops during
operation.
NOTE: This switch also affects the transmission
shift points from F1 to F2, and F2 to F1 :
“Economy Mode
Upshift (F1 to F2) = 2000 RPM. If the emergency steering automatically actuates,
Downshift (F2 to F1) = 1300 RPM. stop the machine as quickly as possible and carry
out an inspection to determine the cause.
“Power Mode
Notify Maintenance personnel immediately.
Upshift (F1 to F2) = 2100 RPM.
Downshift (F2 to F1) = 1400 RPM.
If the key switch is turned ON when the machine is
stopped and the parking brake switch is OFF (un -
locked position), the auto emergency steering will be
actuated after 1.5 seconds. Turn the parking brake
switch to the PARKING (ON/ locked) position.

Emergency Brake Lever (5, Figure 5-2)
The lever (5) actuates For details of the method of releasing the brake
the emergency brake. when it is applied because of failure in the air
system, see BRAKE RELEASE, Page 3-13, of
the Operation & Maintenance Manual.
ENGINE ELECTRONIC CONTROL

SYSTEM
Emergency brake actuated: The following items (7, 8, 9, 11, & 12, Figure 5-2) relate
(APPLIED/ LOCKED position). to the engine electronic fuel control system.
Emergency brake released: If an abnormal engine condition develops, the control
(TRAVEL/ UNLOCKED position). system will record a “fault” code associated with that
condition. By use of a series of indicator lamps and
• If the pressure in the air tank drops below 411.9
switches, the system will display the numerical “fault
kPa (4.2 kg/cm2, 59.7 psi), the emergency brake
code.
is automatically applied.
• If the emergency brake is applied because of a When the keyswitch is turned
failure in the air system, the central warning lamp “On”, the lamps (7,8, 9) should
will flash and the alarm buzzer will sound. illuminate for about 2 seconds
and then turn “Off”, if no “faults
For details of the method of releasing the brake if
are detected in the system.
this happens, see BRAKE RELEASE, Page 3-13,
This is a system lamp test.
of the Operation & Maintenance Manual.
Parking Brake Valve Lever (6, Figure 5-2)

If a light remains
ON, or if a light
FLASHES, then
a ct ive “ fa ult s”
have been de-
tected by the sys-
t em an d t he
e ng in e s houl d
• This lever (6) is used to apply the parking brake. not be started un-
til the condition
PARKING: Parking Brake actuated. (Locked) h as be en cor-
TRAVEL: Parking brake released. (Unlocked) rected.
• When the lever is set to the PARKING position, Refer to DETERMINING “FAULT” CODES.
the parking brake pilot lamp lights up.
During engine operation, if a “fault” is detected in the
system, a light associated with that condition will turn
“ON” and stay on for “Warning faults”, or it will turn
“ON” and “FLASH” for more severe faults that can
Always apply the parking brake when parking or affect engine operation and require immediate atten-
leaving the machine. tion.
• When the lever is set to the PARKING position, if

the transmission shift lever is at any position other
than “N”, the central warning lamp will flash and
the alarm buzzer will sound.
• If the air pressure drops below 215.7 kPa (2.2
kg/cm2, 31.2 psi), the parking brake is automat-
ically applied.

PMC Display (Optional) (10, Figure 5-2)
This area may be used for OPTIONAL Powertrain
Management Controller Display.
If installed, refer to
O pt i o na l E qui p-
• “Warning” faults (light ON) are ones that require ment, Section "M",
attention in the near future, but in most conditions of this Shop Manual
will not greatly affect performance. for further details.
• “Severe” faults (light FLASHING) are ones that

require immediate attention, because the engine
could be significantly affected.
Active fault conditions MUST be corrected as soon
as possible.
Engine Shutdown Light (Stop Engine) Fault Check Switch (11, Figure 5-2)
(7, Figure 5-2) This Fault Check switch, when moved to the
When illuminated, this red engine “ON” (down) position, may be used to acti-
shutdown light vate the engine electronic control system
indicates a seri- diagnostic codes. When the system detects
ou s engi ne a “fault” and one of the indicator lamps (7,
problem exists. 8, 9) illuminates as previously described,
this switch will permit determination of the
kind of “fault(s)” detected.
The “fault” can be engine disabling. Stop the truck in Fault Scroll Switch (12, Figure 5-2)
a safe area, as soon as possible. Shutdown the engine
and notify Maintenance personnel immediately. This Fault Scroll switch may be used to
scroll through the recorded faults held in
memory.
Engine Maintenance Light (Check Engine)
It will display only active fault codes.
(8, Figure 5-2)
To display the next active fault code, move the switch
This amber/yellow light, when illu -
lever to the “up” position momentarily and release
minated, indicates an engine “fault
(switch is spring-loaded to the center “OFF” position).
exists. Current engine operation
may proceed, but the machine Activating the switch again will advance to the next
should be scheduled for check - fault code, etc. Once all active fault codes have been
out/repair as soon as practical. displayed, the fault code display sequence will be
repeated, starting from the first fault code.
Moving the switch lever to the “down” position momen-
Engine Maintenance Light (Protect Engine
tarily and releasing, permits the system to scroll (as
(9, Figure 5-2)
described above) backwards through the fault “list”.
This blue engine maintenance light,
when illuminated, indicates an “out-
of-range” condition exists within the
fuel temperature, coolant, oil, or in-
take air system(s) of the engine.
The light may show initially as a constant “On”, but will

go to “flashing On”, if the condition is allowed to get
worse. Serious engine damage will occur if operation
is continued without correcting the “fault”.

Determining “Fault” Codes Differential Lock Pedal (Optional)
1. To determine an active “fault”, turn the keyswitch If truck is equipped, this pedal (11,
to the “OFF” position and wait until the engine Figure 5-1) is used to actuate the
completely stops. differential lock control.
2. Turn keyswitch to “ON” position (engine NOT When the pedal is depressed, the
running) and hold the Fault Check switch (11) in differential lock is actuated, and
the “ON” position. when it is released, the differential
lock is canceled.
If installed, refer to Optional Equipment, Section "M",

of this Shop Manual for further details.
(12) Hoist Control

3. If there is an active fault: The hoist control (12, Figure 5-1) is a four position,
a. The amber/yellow Engine Maintenance light (8) hand operated control lever located to the left of the
will flash once. operator seat. The hoist control lever and hoist control
b. There will be a 1-2 second pause, and then the valve are connected by a mechanical push-pull control
red Engine Shutdown light (7) will flash out the cable. Refer to Figure 5-3 for an exploded parts view
three digit diagnostic code. of this control.
Each digit is indicated with up to nine light To raise the dump body:
flashes for each digit. There is a short pause (refer also to Operating Instructions, DUMPING”)
between each digit of the fault code.
1. Move Shift
c. After all three digits are flashed, the yellow lamp Lever (1) to
will flash once, and then the red lamp will the “N” posi-
repeat the same fault code sequence as be - tion, and ap-
fore. ply Parking
Brake Valve
Lever (6) to
LOCKED
position.
Move d ump le ver to t he

“RAISE” position and release
dump lever: it will remain in this
4. The system will continue to flash the same fault position until moved to HOLD
code until the Fault Scroll Switch (12) is activated – either manually or by the
again. body-up limit linkage.
EXITING THE DIAGNOSTICS MODE 2. Raise engine RPM to accelerate hoist speed.
When body is near the maximum angle, reduce
Starting the engine, engine RPM (reduce foot pressure on the accel-
o r t u rnin g t he erator pedal) to reduce shock load to the hydraulic
keyswit ch to the system and hoist cylinders.
OFF position, will
EXIT the diagnos-
tics fault flash mode.
If active fault codes have been determined as de -

scribed previously, refer to the appropriate Komatsu
engine manual.

3. When the dump body rises to SAFETY LOCK
the set position (adjusted po-
sition of body positioner) Move hinged lock around dump
dump lever returns to the lever. This device locks the dump
hold position. If desired to lever in the HOLD position.
raise the body further, move
dump lever to raise position
and dump body will rise. If dump lever is released,
lever will return to hold position. Dump body will
stop in that position.
When carrying out inspection on the machine with
4. After material being dumped the body raised, always lock the dump lever in the
clears body, move dump HOLD position, and then install the body up safety
lever to the lower position pins.
and dump body will start to
move down.
5. After lowering the dump

body a certain distance,
move dump lever to the
FLOAT position.
Release the lever and it will return automatically

to the FLOAT position.
The body will move down under its own weight.
NOTE: When traveling, always set the dump lever at
the FLOAT position, regardless of whether or not the
truck is loaded. If the transmission range selector is
moved to any position other than “N” (neutral) when
the dump lever is not at the FLOAT position, the central
warning lamp will light up and the alarm buzzer will
sound.
6. Release Parking Brake Valve Lever.

FIGURE 5-3. DUMP CONTROL LINKAGE
1. Lever 10. Cover 18. Nut 26. Plate
2. Grip 11. Bolt 19. Bracket 27. Bolt
3. Key 12. Nut 20. Bolt 28. Rod
4. Bolt 13. Nut 21. Rod End 29. Bearing
5. Washer 14. Catcher 22. Shaft 30. Lever
6. Washer 15. Screw 23. Bearing 31. Screw
7. Bracket 16. Washer 24. Grease Fitting 32. Bolt
8. Bolt 17. Washer 25. Screw 33. Washer
9. Washer

STEERING COLUMN SERVICE
1. Remove the four screws holding the top and 1. Install steering column (1, Figure 5-4) by sliding
bottom plastic covers in place. yoke (17) onto steering valve. Tighten capscrew
(18) to standard torque. Install pivot bolt (32),
2. Remove wiper switch by removing two mounting
washers (34), bushing (31), and spacer (30).
screws and unplugging the wire harness under
the dash. (Remove gauge cluster first.) 2. Install capscrew (22), plate (21), washer (25),
spring (24), and special hex coupler (23) to tiltlock
3. Remove turn signal switch by removing the two
bracket (20). Install lever (26) and secure with
crews from the steering column clamp and un -
capscrew (27), washer (28).
plugging the harness on the column.
3. Install two capscrews and cover on right side of
4. Remove retarder lever by removing two cap -
steering column.
screws from the clamp and disconnecting the
three air lines. 4. Install four capscrews and cover plate on the left
side of steering column near the floor.
5. Remove four capscrews and cover plate on the
left side of steering column near the floor. 5. Install retarded lever control and connect the three
air lines.
6. Remove two capscrews and cover from right side
of steering column. 6. Install turn signal switch and plug in the harness
on the column.
7. Remove capscrew (27, Figure 5-4) from tilt wheel
mechanism and remove lever. Remove special 7. Install wiper switch and plug in wire harness under
hex coupler (23), spring (24), washer (25), plate the dash.
(21), and capscrew (22) from tilt-lock mechanism.
8. Install the four screws holding the top and bottom
8. Remove pivot bolt (32), washers (34), bushing plastic cover in place.
(31), and spacer (30). Loosen capscrew (18) and
slide yoke (17) from steering valve. Remove
steering column (1).
FIGURE 5-4. STEERING WHEEL AND COLUMN

1A. Steering Wheel 1. Column
2A. Cup 2. Bushing
3A. Plunger 3. Grommet
4A. Bushing 4. Cover
5A. Spring 5. Bearing
6A. Consent 6. Ring
7A. Wire 7. Screw
8A. Spring 8. Shaft
9A. Plate 9. Spider Assembly
10A. Plate 10. Yoke
11A. Insulator 11. Yoke
12A. Cushion 12. Seal
13A. Button 13. Cover

FIGURE 5-4. STEERING WHEEL AND COLUMN

INSTRUMENT PANEL AND INDICATORS
N050105
The instrument panel consists of the gauge and monitor module, speedometer module, monitor
module, service (Hour) meter, odometer, plate, and the parts connected to them.
The gauge and monitor module and speedometer module each have a microcomputer to process
and display the signals from the sensors. Liquid crystal is used for the display area.
The monitors and gauges inside the monitor module and speedometer module are actuated by
the signal from the gauge and monitor module, and the odometer is actuated by signals from the
speedometer module.
The following pages will identify each element of the instrument panel and detail its function and
purpose for the operator.
NO5030 11/98 Operator Controls and Instrument Panel N5-13

FIGURE 5-5. WARNING AND CAUTION LAMPS
1. Central Warning Lamp 2. Action Display Code
W = Warning Monitor Lamp C = Caution Monitor Lamp
E = Electronic Controller Monitor
WARNING & CAUTION LAMPS

1. The Central Warning Lamp is a Red lamp that 2. Action Display Code -
will FLASH whenever any of the Monitor Lamps If any abnormality or maintenance requirement is
(“W”, or “C”, Figure 5-5) are illuminated, or if the detected, an Action Code will be displayed.
Parking Brake is applied and the Transmission Be prepared to follow the recommended action.
Shift Lever is not in the “N”, Neutral position.
Refer to the decal in the upper left-hand corner of
(Refer also to 54, Figure 5-7, later in this Section.)
the windshield (Figure 5-10, later in this Section).
In addition, if any of the Warning Monitor Lamps,
“W”, are illuminated, an alarm buzzer will sound.
“W”, Warning Monitor Lamp -
“E”, Electronic Controller Monitors -
These lamps monitor critical truck functions.
These lamps will flash if any abnormality is
If any abnormality is detected in these systems,
detected in any of the Mechatronics related
the appropriate lamp(s) will light, the Central
systems.
Warning Lamp will flash, and an alarm buzzer
will sound. If any of these lamps illuminate, check the
Action Display Code (2), and be prepared to
When this condition occurs, STOP the truck
follow the recommended action.
as safely and as quickly as possible, check
the Action Display Code (2), and notify
Maintenance personnel.
Do not operate the truck until the system(s)
is repaired and fully operational.
“C”, Caution Monitor Lamp -

These lamps monitor other important truck
functions. If any abnormality is detected in
these systems, the appropriate lamp(s) will
light, and the Central Warning Lamp will flash.
When this condition occurs, check the Action
Display Code (2), and notify Maintenance per-
sonnel as soon as possible.
N5-14 Operator Controls and Instrument Panel NO5030 11/98

FIGURE 5-6. GAUGE AND MONITOR PANEL
1. Air Pressure Monitor 3. Coolant Temperature Monitor

The Coolant Temperature Monitor
The Air Pressure Monitor (1, Figure
(3) is a lamp which indicates a rise
5-6) is a lamp which monitors the air
in the cooling water temperature.
pressure in the air tank. If air pres -
sure in the air tank drops below a When the monitor lamp flashes, run
pre-set value, the lamp will flash. the engine with no load at 1200-
Action code “05" will be indicated. 1500 RPM until the green range of
the engine water temperature
If the lamp flashes, refer to (2) AIR PRESSURE gauge lights.
GAUGE for action.
Action code “05" will be indicated.
2. Air Pressure Gauge
4. Engine Cooling
The Air Pressure Gauge (2)
indicates the air pressure in Water Temperature Gauge
the air tank. The GREEN The Engine Cooling Wate
RANGE should be lighted dur- Temperature Gauge (4) indi -
ing normal operation. cates the temperature of the
cooling water.
If the red range lights up during operations, the alarm
buzzer will sound, the central warning lamp will flash,
and the air pressure monitor lamp (1) will flash at the
same time. If the temperature is normal during operation, the
green range will light. If the red range lights during
When the monitor lamp flashes, stop the machine in a operation, the alarm buzzer will sound, the central
safe area, shift the range selector to “N”, Neutral, and warning lamp will flash and the coolant temperature
run the engine with no load at 1200-1500 RPM until monitor lamp will flash at the same time. If this occurs,
the green range of the gauge lights up. stop the machine and run the engine with no load at
1200-1500 RPM until the green range lights.

5. Torque Converter Oil Temperature 9. High Beam Pilot Lamp
Monitor
The Torque Converter Oil Tempera- The High Beam Pilot Lamp (9) lights
ture Monitor (5, Figure 5-6) is a lamp up when the head lamps are on high
which indicates a rise in the torque beam.
converter oil temperature.
When the monitor lamp flashes, stop the machine and

run the engine with no load at 1200-1500 RPM until
the green range of the temperature gauge lights. 10. Left Turn Signal Pilot Lamp
When the turn signal lever is moved down-
wards, the left turn signal pilot lamp (10)
6. Torque Converter Oil Temperature
flashes.
Gauge
The Torque Converter Oil
Temperature Gauge (6) indi - 11. Right Turn Signal Pilot Lamp
cates the temperature of the
torque converter oil. If the tem- When the turn signal lever is moved up -
perature is normal during op - wards, the right turn signal pilot lamp (11)
eration, the green range will light. If the red range lights flashes.
during operation, the alarm buzzer will sound, the
central warning lamp will light up and the torque con-
verter oil temperature monitor lamp will flash at the
same time. If this occurs, stop the machine and run the
engine with no load at 1200-1500 RPM until the green 12. Speedometer
range lights. The digital Speedometer
(12) indicates the travel
7. Retarder Oil Temperature Monitor speed of the truck in miles
per hour. This figure will ap-
The Retarder Oil Temperature
pear momentarily when the
Monitor (7) is a lamp which warns
keyswitch is first turned “On
that the retarder oil temperature has
to demonstate that all segments are working.
risen. If it flashes, stop the machine,
move the Transmission Range Se-
lector lever to Neutral, and run the 13. Tachometer
engine under no load at 1200-1500
RPM until the warning lamp goes out. The Tachometer
Action code “05" will be indicated. (13) indicates the
engine speed in
Revolutions Per
8. Retarder Oil Temperature Gauge
Minute (RPM).
The Retarder Oil Temperature Gauge (8) indicates the
temperature of the retarde
cooling oil.
During normal operation, a
lamp in the green range should
light up. 14. Shift Limiter Pilot Lamp
If the lamp in the red range lights up during operation,
the alarm buzzer will sound, the central warning lamp The Shift Limiter Pilot Lamp (14)
will flash, and the retarder oil temperature monitor lights up whenever the shift limiter
lamp will flash at the same time. If this happens, stop switch in the center console is acti-
the machine, return the Transmission Range Selector vated.
lever to Neutral, and run the engine at 1200-1500 RPM
under no load, and wait until the lamps in the green
range light up.

15. Lock-up Pilot Lamp 20. Other Mechatronics Monitor
(OPTIONAL)
The Lock-Up Pilot Lamp (15, Figure
5-6) lights up whenever the torque This red indicator (20) flashes whenever
converter is locked up and the any abnormality occurs in the mechatron-
transmission enters direct drive. ics related parts of the PMC (Powertrain
Management Control) system, PLM (Pay-
load Meter) system, and the optional sus-
pension control system.
16. Transmission Shift Position Pilot

Lamp 21. Fuel Level Monitor
The Transmission Shift Position Pilot Lamp This indicator (21) flashes when the re -
(16) will indicate the specific gear range in maining fuel in the fuel tank goes below
which the transmission is actually operating; 170 liters (45 gal). If it flashes, check the
R, N, 1, 2, 3, 4, 5, 6, or 7. fuel level and add fuel.
22. Fuel Gauge

The Fuel Gauge (22) indicates the amount
17. Shift Indicator of fuel in the fuel tank. If there is more than
170 liters (45 gal) of fuel in the tank while
the engine is operating, the green range
lights. If there is less than 170 liters (45
The Shift Indicator (17) indicates the lever position gal) of fuel in the tank, the red range lights.
of the transmission range selector.
23, 24, and 25. (OPTIONAL)

Suspension Mode Display Lamps
This monitor displays the type of suspension mode
being used.
18. Engine Controller Monitor
T hi s OPTIONAL suspension
This red indicator (18) flashes whenever
feature automatically switches
any abnormality occurs in any of the engine
the damping characteristics of
control systems.
the suspension according to
NOT USED with SA12V140Z-1 engine.
whether the truck is carrying a
load, or whether the brake,
steering, or dump controls are
19. Automatic Transmission being operated.
Mechatronics Monitor
Normally, the SOFT mode (25) is used when traveling
This red indicator (19) flashes whenever empty, and MEDIUM (24) is used when traveling
any abnormality occurs in the mechatron- loaded. When using the service brakes or turning
ics related parts of the transmission con- sharply, or when operating the dump control, the sus-
trol system. pension mode is switched to HARD (23) to maintain
the stability of the machine: front and rear, and left and
right.This indicator is present in all instrument panels,
but is inactive in trucks without this option.

26. Service Meter 28. Odometer
The Service Meter (26, Figure 5-6) dis- The Odometer (28) indicates the
plays the total hours of operation for total distance that the truck has
the truck. traveled in miles.
The service meter advances whenever
the engine is operating, even if the
machine is not moving. 29. Power Mode Indicator
27. Service Meter Indicator The Power Mode indicator lights

(29) indicate which of the two fuel
The Service Meter Indicator (27) control modes is in use.
flashes whenever the service meter is
operating.
When the top light (P) is lit, the Power Mode Selector
Switch on the console (3, Figure 5-2) is in “Power
Mode”.
When the bottom light (E) is lit, the Power Mode
Selector Switch is in the “Economy Mode”.
FIGURE 5-7. INDICATORS AND CONTROLS PANEL -

FULL OPTION CONFIGURATION
OPTIONAL EQUIPMENT (Figure 5-7)

When the truck is equipped with either, or both, of the
OPTIONS, Exhaust Brake Switch (52), or Fog Light
Switch (53), then the instrument panel arrangement for
items 34, 35, and 36 will be as shown in Figure 5-7.
If the truck is NOT equipped with either of these
OPTIONS, then the standard panel arrangement for
items 34, 35, and 36 will be as shown in Figure 5-8.
FIGURE 5-8. STANDARD CONFIGURATION

30. Coolant Level Monitor 35. Front Brake Off Switch
The Coolant Level Monitor (30, Fig-
ure 5-7) indicates a low radiator
coolant level. If this monitor lamp
flashes and alarm buzzer sounds,
stop truck, shutdown engine, and
add coolant as required.
This switch (35) is used to change the braking method

31. Engine Oil Pressure Monitor according to the road conditions.
The Engine Oil Pressure Monitor This position (out/light “Off”) is used when
(31) indicates low engine oil pres - traveling on normal road surfaces.
sure. Braking force is applied to both front and
If the lamp flashes and alarm buzzer rear wheels.
sounds, stop the engine and carry
out inspection. This position (in/light “On”) is used when
Action code “04" will be indicated. traveling on slippery roads.
Braking force is applied only to the rear
wheels.
32. Charge Monitor This switch is present in all instrument panels, but is
The Charge Monitor (32) indicates inactive in trucks without this option.
an abnormality in the charging sys-
tem while the engine is running.
If the monitor lamp lights up, check 36. Panel Dimmer Switch
the charging circuit.
Action code “01" will be indicated. The Panel Dimmer Switch (36) is used to
adjust the brightness of the lighting inside
the monitor panel and pilot lamps.
33. Transmission Oil Filter Monitor
The Transmission Oil Filter Monitor
(33) warns of clogging of the trans- Adjust as follows:
mission oil filter. If the monitor light • To INCREASE brightness,
lights up, replace the transmission turn CLOCKWISE.
filters, and check for contamination
in the oil. • To DECREASE brightness,
Action code “01" will be indicated. turn COUNTERCLOCKWISE.
34. Hazard Warning Lights
The Hazard Warning Light

switch (34, Figures 5-5, and
5-6) causes all turn signal
lights to flash.
The toggle switch is an “ON-OFF” type.

37. AISS/Auto Switch 39. Starting Switch
The Starting Switch (39, Figure
The AISS (Automatic Idle Se-
5-7) is a three-position keyswitch:
lector Switch, 37, Figure 5-7)
may be positioned to LOW or “ OFF” Position – Key inser-
AUTO as desired. This switch is tion/withdrawal position – None of
used by the operator to control the electrical circuits activate in
the idle speed of the engine. this position.
Turn the switch to “OFF" to stop the engine.
LOW position (button in/light “ON”) is the
"manual position" and is used when fine
“ON” – Lamp circuits activate in this position.
control movements are needed, such as when parking,
or driving in/out of confined spaces. “START” – At this key position, the starting motor will
crank the engine. Release the key immediately after
AUTO position (button out/light “OFF”)
engine starts; the key will return automatically to “ON”.
is used for normal operations.
The following conditions occur: (Refer to “STARTING THE ENGINE”, earlier in this
Section.)
1. When the machine is stopped, the idling speed is
automatically set to LOW speed when the parking 40. Pilot Lamp Bulb Check Switch
brake or retarder is ON. When the parking brake
is released to start traveling, the idling speed is Turn the starting switch (39) to
automatically set to HIGH speed. “ ON” and press the Pilot
2. If the coolant temperature is low, the idling speed Lamp Bulb Check Switch (40)
is automatically set to HIGH speed to reduce the to check if bulbs will light.
time taken for the warming up operation. All pilot lamp bulbs should
light.
38. Manual Starting Aid Switch
T hi s t r uck i s
41. Rear Brake Pilot Lamp
equipped with an
Automatic Co ld
The Rear Brake Pilot Lamp (41)
Start Aid.
lights up when the service brake is
The Cold Starting depressed or the retarder control
Aid energizes the lever is pulled to actuate the rear
electric heaters in brake.
the engine intake manifold.
Under normal conditions, there is no need to use this
MANUAL switch. 42. Body Float Caution Monitor
If the outside temperature is below -5°C (23F) and the
When the dump body control lever
prelube starter runs a long time, this manual switch can
is set to any position other than
be pushed “IN” for 2-3 seconds before starting the
FLOAT, or the body is not seated on
engine to maintain engine pre-heating.
the frame, the Body Float Caution
(Refer to “STARTING THE ENGINE IN COLD Monitor (42) lights up.
WEATHER”, earlier in this Section.)
The Starting Aid Switch (38) is spring-loaded to the
“OUT/OFF” position. When traveling, always set the lever to FLOAT position
with the body seated.
DO NOT PUSH COLD STARTING AID BUTTON

AFTER ENGINE HAS STARTED!
SERIOUS DAMAGE TO ENGINE MAY OCCUR!

43. Parking Brake Monitor 48. Steering Oil Temperature
This lamp (48) indicates a rise in the
steering oil temperature. If the lamp
The Parking Brake Monitor (43 comes on, stop the truck and run
lights up when the parking brake is the engine with no load at 1200-
applied. 1500 rpm until the caution lamp
goes out.
44. Emergency Steering Monitor 49. Maintenance Required (Optional)

If the emergency steering switch (located on center
console) is activated, this lamp (44) The Maintenance Monitor Lamp
lights up. (49, Figure 5-7) will illuminate if the
PMC (Powertrain Management
It also lights up when the auto emer-
Controller), detects any of the fol -
gency steering is actuated because
lowing conditions:
an abnormality has occurred in the
steering hydraulic circuit during
travel. Brake Disc wear indication - right or left rear
Low battery liquid level
Low engine oil level
Air cleaner restricted
45. Exhaust Brake (Optional)
Low front brake oil level
Low retarder cooling oil level
Low hydraulic oil level
The exhaust brake pilot lamp (45) Retarder cooling oil filter restricted
lights up when the exhaust brake is Hydraulic oil filter restriced.
actuated.
50. Side Slope Warning (Optional)
When the dump body is raised, this
warns the operator that the ma -
46. Cold Start chine has tilted beyond the safety
range to the left or right. If this moni-
The cold start pilot lamp (46) lights tor (50) flashes, lower the body, and
up when the automatic cold start is move the machine to a safe, stable
activated or the manual cold start place.
switch on the instrument panel is Action code “07" will be indicated.
depressed.
51. Rear Brake Caution Lamp

47. Differential Lock (Optional) This lamp (51) flashes when the rear
brake is operated and the over-
stroke sensor installed to the brake
This lamp (47) lights up (if truck is chamber contacts the brake piston.
equipped) when the differential lock Brake oil pressure below normal
pedal is depressed and the differen- level is the usual cause.
tial lock is actuated. If this lamp flashes, check the rear
brake system immediately.
After inspecting and repairing the rear brake system,

be sure to push in the over-stroke sensor installed to
the brake chamber. If this operation is neglected, the
brake line trouble warning will continue to operate.

52. Exhaust Brake Switch (Optional) 54. Central Warning Lamp
(Red Convex Lens)
For operation of the Exhaust Brake Switch (52, Figure

5-7), refer to the following switch positions: This Central Warning lamp (54, Figure 5-7) flashes
The exhaust brake is actuated when the whenever an abnormality has occurred in any one of
foot brake is depressed or the retarder the following systems:
control lever is operated and the torque Battery Charging Monitor
Position Off converter is in the lockup condiiton. Emergency Steering Monitor
Parking Brake Monitor
The exhaust brake is actuated when the Body Float Monitor
accelerator pedal is released and the Automatic Transmission Monitor (Mechatronics)
Position On torque converter is in lockup condition. Suspension Monitor
Fuel Level Monitor.
(Refer earlier in this Section to “ENGINE START-UP
SAFETY PRACTICES” and “WARNING & CAUTION
LAMPS”.)
53. Fog Light Switch (Optional) This lamp flashes, and at the same time an alarm
buzzer sounds intermittently, whenever an abnormal-
ity has occurred in any one of the following systems:
Air Pressure Monitor;
Coolant Temperature Monitor;
Torque Converter Oil Temperature Monitor;
Retarder Oil Temperature Monitor;
Coolant Level Monitor;
Engine Oil Pressure Monitor; or
Transmission Oil Filter Monitor.
Fog Lights are optional equipment. If truck is equipped, This lamp will also flash and the alarm buzzer will
they are useful in foggy conditions and heavy rain. sound, if the parking brake is applied and range
selector lever is not at Neutral.
Fog lights are off when switch (53, Figure
5-7) is in this position (out/light “Off”).
Depressing the switch to this position

(in/light “On”) turns fog lights on.

FIGURE 5-9. INSTRUMENT PANEL - RIGHT SID
55. Temperature Adjustment Lever 57. Air Selector Lever

The Temperature Adjustment Lever (55, Figure 5-9) is Note: Turn blower switch (56, Figure 5-9) to lower
used to adjust the cab air temperature for heating or position before moving air selector lever.
cooling.
The Air Selector Lever (57) selects the source of air.
Move the lever to the left toward “WARM” (red bar) for Outside air enters through a filter and is sent to the cab
higher temperature. to ventilate the inside the cab. In this way, a pleasant
working environment is always maintained even on
Move the lever to the right toward “COOL” (blue bar)
dusty jobsites.
for lower temperature.
Move the lever to the left toward “FRESH” for outside
56. Blower Switch air. Air is taken from outside to mix with the air inside
the compartment.
The Blower Switch (56) is a four
position switch to control fan Move the lever to the right toward “RECIRC” for recir-
speed. Move the lever to fan posi- culation of cab air only. This is generally used to cool
tion desired. the cab quickly.
The positions – from left to right –

58. Vent Selector Lever
are as follows:
The Vent Selector Lever (58) directs the cool or warm
air through one or more of the following outlets: front
•
“OFF” – Low• – Medium – and High • vents; foot vents; or defroster vents.
Move the lever to the left toward “VENT” to direct
Low, Medium, and High are indicated by circular marks heated or cooled air through the front vents (59).
of increasing size.
Move the lever to the center to “HEAT” to direct air to
the foot vents and defroster vents for heating and
dehumidifying.
When in the “OFF” position, the air conditioner com-
pressor is de-activated. Move the lever to the right to “DEF” to direct air to the
defroster vents to remove and/or prevent mist from
forming inside the windshield.

59. Air Vent 62. Correction Code Display
Air Vents (59, Figure 5-9) are provided for circulation When an action code appears in this area (62, Figure
of cooled or heated air through the cab. 5-7), refer to the decal (Figure 5-10) in the upper
left-hand corner of the windshield.
60. Glove Box Storage Compartment
This area (60) provides a small storage space that may
be used for pencils, note paper, etc. In some models
it may be used for OPTIONAL EQUIPMENT, such as,
Payload Meter.
61. Air Conditioner Switch

When the Air Conditioner Switch (61) is pressed, the
blue lamp inside the button lights up, and the air
conditioner compressor is activated. This is used to
provide cold air or to dehumidify the air. If the blower
switch (56) is in “OFF” position, the air conditiner
compressor will be turned off even if the air conditioner
switch (61) is in the “ON” position. The light in the air
conditioner switch will go out when the blower switch
is turned off.
Follow the instructions to the right of the code number

displayed on the panel monitor.
FIGURE 5-10 CORRECTION CODE DECAL

SECTION P
LUBRICATION AND SERVICE
INDEX
LUBRICATION AND SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-1
LUBRICATION SPECIFICATIONS CHARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-1

SERVICE CAPACITIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-1
ANTI-FREEZE SPECIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-1
LUBRICATION CHART – OIL AND GREASE SPECIFICATION . . . . . . . . . . . . . . P2-2
10 HOUR (DAILY ) LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . P2-3
250 HOUR LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . . . . . P2-9
500 HOUR LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . . . . . P2-11
1000 HOUR LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . . . . P2-12
2000 HOUR LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . . . . P2-13
HYDRAULIC TANK SERVICE AND FILLING INSTRUCTION . . . . . . . . . . . . . . . . . . P2-14

Hydraulic Tank Filter Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-15
Hydraulic Tank Breather Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-15
HIGH PRESSURE HYDRAULIC FILTER SERVICE . . . . . . . . . . . . . . . . . . . . . . . . P2-16
TRANSMISSION FILTER SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-18
PERIODIC REPLACEMENT OF COMPONENT PARTS FOR SAFETY DEVICES . . . . . . . P2-19
P01017 11/ Index P1-1

NOTES
P1-2 Index P01017 11/

LUBRICATION AND SERVICE
Preventive Maintenance will contribute to the long life The service intervals presented here are in hours of
and dependability of the Komatsu Haulpak truck and operation. These intervals are recommended in lieu
its components. The use of proper lubricants and the of an oil analysis program which may determine
performance of checks and adjustments at recom - different intervals. However, if the truck is being
mended intervals is most important. operated under extreme conditions, some, or all, of the
intervals may need to be shortened and the service
Lubrication requirements are referenced to the lube
performed more frequently.
key found at the top of the Lubrication Specifications
Chart (next page).
Refer to engine manual when servicing the engine or
For detailed service requirements for specific compo- any of its components.
nents, refer to the shop manual section for that com -
COOLING SYSTEM
ponent (i.e. Section “G” for Final Drive, Section “H” for ANTI - FREEZE RECOMMENDATIONS
Suspensions, etc.).
(Ethlyene Glycol Permanent Type Anti-Freeze)
330M SERVICE CAPACITIES Percentage of Protection
U.S. Anti-Freeze To
Liters
Gallons 10 +23°F – 5°C
Engine Crankcase 147 39 20 +16°F – 9°C
including lube oil filters. [138] [37] 25 +11°F – 11°C
Cooling System: 256 66 30 + 4°F – 16°C
35 – 3°F – 19°C
Hydraulic System: 40 – 12°F – 24°C
Front Brake Oil Tank 2 0.53 45 – 23°F – 30°C
Rear Brake Cooling Oil Tank 366 96.6
50 – 34°F – 36°C
[248] [65.5]
55 – 48°F – 44°C
Steering/Hoist Oil Tank 248 65.5
[145] [38.3] 60 – 62°F – 52°C
Refer to “Hydraulic Tank Service”, Use only anti-freeze that is compatible with engine as
page P2-14. specified by engine manufacturer.
Fuel Tank
Diesel Fuel–ASTM D975 No. 2 * 1250 330
* Below -10°C (14°F) use No. 1
Final Drive Case
250 66
(Differential & both planetaries)
Transmission Case: 125 33
including torque converter. [102] [26.9]
NOTE: Top number is for initial dry system fill:
includes hoses, internal valve cavities, etc.
Bottom [number], if present, is service refill.
Refer to Transmission Oil Level Check, page P2-7.
P02023 11/98 Lubrication and Service P2-1

P2-2 Lubrication and Service P02023 11/98
10 HOUR (DAILY) INSPECTION
Prior to each operating shift, a “walk around” inspec- Truck Serial Number ________________________
tion should be performed. Check the truck for general
condition. Look for evidence of hydraulic leaks; check Site Unit Number ___________________________
all lights and mirrors for clean and unbroken lenses; Date:______________Hour Meter______________
check operator’s cab for clean and unbroken glass;
check frame, sheet metal and body for cracks. Notify Name of Service person_______________________
the proper maintenance authority if any discrepancies
are found. Give particular attention to the following:
FLUID LEVELS & OTHER CHECKS -

With Engine Stopped
For the following checks, park the truck on a level
surface, lower the dump body, and shut down the
engine.
COMMENTS √’d INITIALS
a. Radiator -
C he ck cool ant
level (2). Coolant
level should be
b et w een FUL L
and LOW.
If coolant is low,
fill though cap (1)
to FULL level with proper mixture as shown in
Cooling System Recommendation Chart.
CAUTION - If engine has been running, allow cool-
ant to cool, before removing the fill cap or draining
radiator. Serious burns may result if coolant is not
allowed to cool.
* - Check that there is no oil or other contaminants
in the cooling system.
* - If the volume of added coolant is significant,
check for possible leakage.
Tighten cap securely.
b. Batteries - Check electrolyte level and add distilled
water if necessary. Inspect battery box cover for
looseness or damage.
c. Front Brake Oil Tank -
Check oil level (2).
Add oil if necessary.
Remove cap (1). Use
SAE 10W, Engine Oil
ONLY. After adding oil,
tighten cap securely.
d. Drain moisture from tanks by

pulling chains (1) on moisture
drain valves. Check air tanks
and lines for leaks. Check the
brake chambers for leaks,
damage, etc.

10 HOUR (DAILY) INSPECTION (continued)
e. Check air cleaner service indicator (1). If the RED COMMENTS √’d INITIALS
area is showing in the indicator, the air filters must
be cleaned or re-
placed before oper -
ating truck.
Push the indicator
reset button to return
the red piston to its
normal position.
f. Steering, Hoist Oil Tank - Check oil level (1) in tank,

oil should be visible in the sight glass.
Add oil, if necessary. Lube key “C”.
Refer to “Hydraulic
Ta nk Servi ce” ,
page P2-14.
g. Rear Brake Cooling Oil Tank - Check oil level (2)

in tank, oil should be visible in the sight glass.
Add oil, if necessary. Lube key “E”.
h. Fuel Tank - Inspect the fuel gauge (2) and note the
quantity indicated.
Compare this indication later against the fuel

gauge reading in the instrument panel of the op-
erator cab. Fill tank (cap, 1) as required. After
filling tank, tighten cap securely.
i. Differential - Truck should be on level surface, oil
level should be even with plug hole or at plug hole.
Refill with oil as necessary. Lube key “B”.
Check final drive housing breather. Clean or re -
place breather, if obstructed. Check for leakage
around final drive housing and oil disc brake hous-
ings and the hoses connected to the housings.

ENGINE
1. Check alternator and fan belts for proper tension,
alignment, and general condition.
2. Engine Oil Level- (lower right side)
(Engine stopped for at least 15 minutes)
a. Remove dipstick (1) and
wipe off with a clean,
lint-free cloth.
b. Insert dipstick all the
way into full depth.
c. Remove dipstick again.
Oil level should be be -
tween “H” and “L” marks.
d. If oil level is below the “L” mark, add oil through
filler (2) as required. Refer to the engine man-
ual for oil recommendations. When done,
tighten cap securely.
NOTE: If oil level is above the “H” mark, deter-
mine cause, then drain excess quantity of oil.
WHEELS AND TIRES
TIRES
Inspect all tires for proper inflation and wear;
Cuts, damage or “bubbles”;
Debris embedded in cuts or tread;
Rocks that might be lodged between dual tires.
Left Front Tire Pressure
Left Rear Outside Tire Pressure
Left Rear Inside Tire Pressure
Right Rear Outside Tire Pressure
Right Rear Inside Tire Pressure
Right Front Tire Pressure

WHEELS COMMENTS √’d INITIALS
a. Check to see that all wheel lugs/wedges are in
place and tight.
b. Inspect rear wheels for any leakage that may be
coming from inside the wheel housing that would
indicate planetary leakage.
c. Check rear dual wheels for any rocks that might be
lodged between dual tires.
d. Check that rock ejector is in good condition and
straight, so that it can not damage a tire.
After each wheel mounting operation, recheck

wheel mounting capscrew tightness after 4 – 5
hours of operation. Check again at the end of the
shift, and then periodically until all capscrews hold
at the prescribed 225 ±25 kg.m (1628 ±180 ft.lbs.)
torque (dry threads). This is prescribed for both
front and rear wheels.
Tighten wheel nuts in the order as shown in the
diagrams.

OPERATIONAL CHECKS -
With Engine Running
For these checks, park the truck on a level surface,
lower the dump body, and operate engine at approxi-
mately 1000 RPM, until air pressure, coolant tempera-
ture, engine oil temperature, and transmission oil
temperature gauges all indicate “Normal (green
range”.
NOTE: Be certain that the Parking Brake is applied and
the Transmission Range Selector is in the Neutral
(“N”) position, then operate engine at low idle while
performing the following checks:
The engine will be running during the following

procedures. Keep away from all moving parts,
such as fans, belts, pulleys, driveshafts, etc.
1. Inspect engine and turbochargers for leaks, vibra-

tions or odd noises.
2. Check the transmission oil level at thelower marks

(2) on transmission oil
pan decal.
a. Use the upper marks
(1) when engine is
cold or engine has
been stopped for 8
hours or more.
b. If oil level is below the lower
“L” mark, add oil through
filler (1) as required.
Lube key “F”.
Before leaving this posi-
tion, look to see that there
is no leakage or any other unusual condition
with transmission or drive shafts.

NOTES

250 HOURS SERVICE
INITIAL 250 HOURS SERVICE Truck Serial Number ________________________
Perform the following maintenance after running the Site Unit Number ___________________________
machine for the first 250 hours.
Date:______________Hour Meter______________
Thereafter, these services are to be accomplished at
the 500/1000/2000 hour interval as scheduled. Name of Service person_______________________
Refer to pages P2-11, -12, & -13.
a. Steering, Hoist Oil Tank and Rear Brake Cooling
Oil Tank, replace elements.
b. Transmission Case, change oil.
c. Steering, Hoist Oil Tank, change oil.
d. Rear Brake Cooling Oil Tank, change oil.
e. Differential Case, change oil.
f. Final Drive Case, change oil.
g. Fuel Filter, replace cartridges.
h. Transmission Oil Filter, replace elements.
EVERY 250 HOURS SERVICE

1. Lubricating - Apply ample grease supply to grease
fittings.
- Dump body hinge pin - 2 points.
- Rear Suspension - 4 points.
- Axle Supports pins - 8 points.
- Hoist Cylinder pin - 4 points.
- Front Suspension Assembly - 8 points.
- Steering Cylinder pin - 4 points.
- Steering Linkage - 5 points.
- Drive Shafts - Front, 2 points, Rear, 3 points.
2. BATTERY - Check electrolyte level and add dis-
tilled water if necessary to maintain proper level.

250 HOURS SERVICE
(continued)
4. ALTERNATOR BELT - COMMENTS √’d INITIALS
Check condition of the 24V alternator belt for
evidence of belt slippage, looseness or physical
defects.
5. AIR CONDITIONER COMPRESSOR BELT
Check for condition of belt and proper tension.
6. TRANSMISSION CASE BREATHERS - Remove
breathers, disassemble breathers remove filter
element, clean in solvent. Dry with air pressure
and reassemble then reinstall.
7. HYDRAULIC TANK BREATHERS - Remove
breathers, disassemble breathers remove filter
element, clean in solvent. Dry with air pressure
and reassemble then
8. DIFFERENTIAL CASE - Check oil level. Use lube
key “B”.
9. DIFFERENTIAL CASE BREATHER - Remove
breather. Wash to flush out the dirt from inside.
Reinstall after cleaning.
10. FINAL DRIVE CASE - Check oil level in R.H. and
L.H. case. Use lube key B”.
11. DRIVE SHAFT - Inspect drive shafts for any ab -
normalities: loose joints, worn splines or bearings,
unusual vibration of shaft. Refer to Section “C”,
Drivelines and Adapter.
Notify the proper maintenance personnel, if any
discrepancies are found. Use lube key “D” chart.
12. PARKING BRAKE - Measure brake pad for proper
wear and thickness.
Refer to Section “J”, Brake System, “Brake Circuit
Checkout And Adjustment”, for proper inspection,
procedures and tools. Use lube key “D” chart.

500 HOUR SERVICE
Truck Serial Number ________________________
In addition to the 250 hour lubrication and inspection Site Unit Number ___________________________
schedule, perform the following:
Date:______________Hour Meter______________
Name of Service person_______________________

1. FAN BELT - Check for alignment, condition of belt,
and proper tension.
Refer to Section “C”, Engine and Cooling System.
2. RADIATOR FINS - Check for clogged or damaged
fins. Notify the proper maintenance personnel if
any discrepancies are found.
3. TRANSMISSION OIL FILTER -
Remove and replace filter element.
Refer to "Transmission Filter", page 2-18.
4. FRONT DISC BRAKE - Measure disc pad for
proper wear and thickness.
Refer to Section “J”, “Brake Circuit Checkout and
Adjustment”, for specifications and limits.
5. ENGINE - Refer to the engine manual for oil
recommendations and capacity.
- change engine oil.
- change engine lube oil filters. (Figure 2-1)
6. FUEL FILTER - Remove and replace two fuel filter
elements. (2, Figure 2-2)
7. CORROSION RESISTOR - Remove and replace
four corrosion resistor elements.
8. BY-PASS FILTERS - Remove and replace two
engine by-pass filter elements. (1, Figure 2-2)
FIGURE 2-2. FILTERS - Upper Left Front of Engine

FIGURE 2-1.LUBE OIL FILTERS 1. Engine Oil 2. Fuel Filters
Upper Right Front of Engine By-Pass Filters

1000 HOUR SERVICE
Truck Serial Number ________________________
In addition to the 250 and 500 hour lubrication and Site Unit Number ___________________________
inspection schedules, perform the following: Date:______________Hour Meter______________
Name of Serviceperson________________________
1. LUBRICATING
- Transmission mount - 1 point. - Lube key “D”.
- Parking brake linkage - 6 point - Lube key “D”.
2. TRANSMISSION CASE
Drain oil, remove and replace element. Remove
clean, and reinstall strainer. Refill tank with oil
approximate 28 gal (106 l). Refer to “Lubrication
Chart” for fuel, coolant and lubricants and type of
oil to use. Lube key “F”.
3. STEERING, HOIST OIL TANK and REAR BRAKE
COOLING OIL TANK.
When removing tank caps, turn cap slowly at first

to relieve inner pressure. Remove cap only after
pressure has been completely relieved.
Any operating fluid, such as hydraulic oil or brake
fluid escaping under pressure, can have sufficient
force to enter a person’s body by penetrating the
skin. Serious injury and possibly death may result
if proper medical treatment by a physician familiar
with this injury is not received immediately.
Remove (3) filter elements from tank. Clean all

removed parts and the inside of element case.
Install new filter elements.
Refer to “Hydraulic Tank Service”, page P2-14.
4. REAR BRAKE WEAR -

Refer to Section “J”, “Brake Circuit Checkout and
Adjustment”, for specifications and proper inspec-
tion procedure.
Carry out inspection when the oil temperature is

below 60°C (140°F ). Hot oil may cause serious
personal injury.

EVERY 2000 HOUR SERVICE
Maintenance for every 250, 500 and 1000 hours Truck Serial Number ________________________
should also be carried out at this time. Site Unit Number ___________________________
Date:______________Hour Meter______________
1. STEERING, HOIST OIL TANK Serviceperson Name________________________
Drain oil from tank and refill tank to specified level, COMMENTS √’d INITIALS
capacity 162 l (43 gal.). Refer to “Lubrication
Chart” for type of oil to use. Lube key “C”.
Refer to “Hydraulic Tank Service”, pageP2-14.
Remove / replace 2 high pressure filter elements.
Refer to "High Pressure Hydraulic Filters",
pageP2-16.
2. REAR BRAKE COOLING OIL TAN
Drain oil from tank and refill tank to specified level
capacity 268 l (71 gal.). Lube key “E”. To reduce
rear brake “squeal”, use only SHELL DONAX - TD
Oil or BP TRACTRAN UTH. If these oils are not
available, use Lube key “C”.
Refer to “Hydraulic Tank Service”, page P2-14.
3. FINAL DRIVE CASE
Position machine so that casting line is horizontal
and drain plug is at the bottom. Drain oil and
reinstall plug, remove fill plug at castline and fill to
specified level. This operation is performed on the
right and left hand final drives. Capacity is 64 l (17
gal.) each side.
Refer to “Lubrication Chart” for type of oil to use.
Lube key “B”.
4. DIFFERENTIAL CASE
Drain oil from differential and refill to the specified
level: capacity 130 l (34 gal.).
Refer to “Lubrication Chart” for type of oil to use.
Lube key B”.
5. VIBRATION DAMPER, ENGINE
Inspect damper for cracks or separation on rubber
surfaces. If any defects are noted, replace with
new vibration damper.
6. EMERGENCY RELAY VALVE
Disassemble emergency relay valve, clean and
inspect for damaged or worn parts. Replace all
rubber parts also any that were found defective,
then reassemble.
7. ENGINE FRONT TRUNNION
Apply grease. Lube Key “D
8. DUMP CONTROL LINKAGE - 3 points
Apply grease. Lube key “D

HYDRAULIC TANK SERVICE
Filling Instructions
(Hoist Oil Supply)
1. Park the truck on a level surface, lower the dump
body, and shut down the engine.
When removing tank cap, turn cap slowly at first

pressure has been completely relieved.
Any operating fluid, such as hydraulic oil or brake
fluid escaping under pressure, can have sufficient
skin. Serious injury and possibly death may result
if proper medical treatment by a physician familiar
FIGURE 2-3. HYDRAULIC TAN
1. Filter Covers 6. Brake Oil Drain
2. Turn the oil filler cap (3, Figure 2-3) slowly coun -
2. Bolts 7. Brake Cooling Oil
3. Hydraulic Oil Filler Cap Sight Glass
3. Fill tank with recommended oil until oil is visible in 4. Hydraulic Oil Level 8. Brake Cooling Oil
the sight glass (4). Refer to “Lubrication Chart” for Sight Glass Filler Cap.
type of oil to use. Lube key “C”. 5. Hydraulic Oil Drain 9. Breather
Hydraulic tank refill capacity:
162 Liters (42.8 gal.) Filling Instructions
4. Replace fill cap. (Rear Brake Cooling Oil Supply)
1. Park the truck on a level surface, lower the dump
5. If hydraulic components have been removed and
body, and shut down the engine.
lines drained, start the engine and raise the dump
body 2-3 times to circulate oil and fill all voids.
When removing tank cap, turn cap slowly at first

Before raising body, be certain that the truck is in pressure has been completely relieved.
an area where there is sufficient overhead clear - Any operating fluid, such as hydraulic oil or brake
ance to allow the body to be raised. fluid escaping under pressure, can have sufficient
6. Lower the dump body and shut down the engine skin. Serious injury and possibly death may result
and repeat steps 2. through 4. if necessary. if proper medical treatment by a physician familiar
2. Turn the oil filler cap (8, Figure 2-3) slowly coun -
3. Fill tank with recommended oil until oil is visible in
the sight glass (7).
To reduce rear brake “squeal”, use ONLY SHELL
DONAX - TD Oil or BP TRACTRAN UTH. If these
oils are not available, use Lube key “C”.
Rear Brake Oil tank refill capacity:
268 Liters (70.8 gal.)

HYDRAULIC FILTERS
Filter Replacement


counterclockwise to release internal tank pres -
sure.
3. Remove bolts (2) on filter covers (1).
4. Remove the elements (2, Figure 2-4) from hous -
ing.
FIGURE 2-4. HYDRAULIC TANK FILTERS
5. Thoroughly clean filter housings, covers (4) and
bypass valve (3) components. 1. Hydraulic Tank 3. Bypass Valve
2. Filter Element 4. Cover
6. Install new elements. Install bypass valves and
covers. Tighten bolts (2, Figure 2-3) to standard
torque.
7. Check oil level; oil must be visible in sight glass.
HYDRAULIC TANK BREATHER
Cleaning
1. Shut down the engine and open hydraulic tank filler
caps slowly to relieve any internal pressure.
2. Clean dirt accumulation from area of breather (9,
Figure 2-3).
3. Remove the breather from the tank.
4. Remove snap ring (1, Figure 2-5), cover (2) and
filter element (3).
5. Clean breather element in solvent and blow dry.
Clean remaining parts in solvent and dry thor -
oughly. Replace element, if element appears
damaged or doesn’t clean up thoroughly.
FIGURE 2-5. HYDRAULIC TANK BREATHER
6. Install element, cover and snap ring.
1. Snap Ring 3. Element
7. Install breather element on hydraulic tank. 2. Cover

HIGH PRESSURE HYDRAULIC FILTERS
Filter Assembly Removal

Clean dirt accumulation from the high pressure
hydraulic filters and tube connections in front of
the hydraulic tank.

sufficient force to enter a person’s body by pene -
sibly death if proper medical treatment by a
immediately.

counterclockwise to release internal tank pres -
sure.
3. Place a receptacle under the filters to receive
FIGURE 2-6. HIGH PRESSURE FILTERS & PIPING
hydraulic oil which will drain from filters when
disconnected. 1. Capscrew 8. Capscrew
4. Remove capscrews (1, 4, & 8, Figure 2-6), wash- 2. Washer 9. Washer
ers (2, 5, & 9), and split flages (10) securing filters 3. O-Ring 10. Split Flange
(7). 4. Capscrew 11. Bracket (on Hyd. Tank)
5. Washer 12. Washer
Move hydraulic tubes away from filter housings. 6. U-Bolt 13. Nut
5. Remove nuts (13) and washers (12) holding U- 7. Filter Assembly
bolts (6) to bracket (11). Remove filter assemblies
(7). Discard O-rings (3).
Plug or cover all open hydraulic connections to
prevent entry of contaminants and move filter
assemblies to a clean service area.
Filter Assembly Installation

1. Remove plugs and/or covers from connections. 4. Carefully align all components and connections to
Install new O-rings (3, Figure 2-6) in all locations. prevent any binding or kinking and then begin
Install filter assemblies (7) to outlets and install tightening all capscrews and nuts sequencially to
capscrews (1 & 4), washers (2 & 5). Do not tighten final standard torque.
capscrews to final torque at this time.
2. Move hydraulic tubes to filter housings inlets and
reconnect with capscrews (8), washers (9), and
split flages (10). Do not tighten capscrews to final Tighten all connections before starting engine and
torque at this time. applying hydraulic pressure.
3. Install U-bolts (6) holding filter assemblies (7) to
5. Start engine and check for leaks before releasing
bracket (11). Install washers (12) and nuts (13).
truck for service. Check hydraulic tank oil level; oil
Do not tighten nuts to final torque at this time.
must be visible in sight glass (4, Figure 2-3).

Filter Element Replacement
1. Place filter assembly (Figure 2-7) on work bench. 3. Install new element (2) into filter housing (1) using
Using a spanner tool at both ends, hold housing new O-Ring (3) and Backup Ring (4).
(1) and loosen (counter-clockwise) inlet housing
4. Install inlet housing (5) to filter housing (1) and
(5).
tighten to 10 - 12 kg.m (73 - 87 ft. lbs.) torque.
Remove inlet and then remove filter element (2)
5. Refer to "Filter Assembly Installation" and install
from housing. Discard O-Ring (3) and Backup
on truck.
Ring (4).
NOTE: Filter Elements should be replaced every 2000
2. Thoroughly clean filter housing and inlet housing.
hours*, and after any debris-producing component
Using clean hydraulic oil, lightly lubricate sealing
failure within the hydraulic system.
surfaces.
* More frequent replacement may be required in very
dusty/dirty environments.
FIGURE 2-7. FILTER ASSEMBLY

1. Filter Housing 3. O-Ring 5. Filter Housing Inlet 7. Spanner Hole
2. Filter Element 4. Backup Ring 6. Spanner Hole

TRANSMISSION FILTER
The transmission filter element (Beta 25 = 200) should

be replaced every 500 hours of operation or sooner if
the warning light indicates high restriction. This main-
tenance interval may be be increased or reduced,
depending on operating conditions, by observing the
warning light indicator.
This filter assembly is equipped with a pressure switch
to indicate a high pressure differential (restriction). The
switch will close @ 2.5 kg/cm 2 (35 psi) by-pass pres-
sure. Actual by-pass of the hydraulic fluid does not
occur until 3.5 kg/cm2 (50 psi) by-pass pressure.
Service
1. Remove drain plug (7, Figure 2-8) and drain the oil
from the filter housing. Tighten plug after all oil is
drained.
2. Unscrew filter bowl (4) from head assembly (1).
3. Remove the element and thoroughly clean and dry
all component parts.
4. Coat a new seal (9) with clean engine oil and
install.
5. Install a new element (5) and install the filter bowl
(4) into the head assembly (1).
6. Start the engine and let it idle for 5 minutes. Stop
engine and check for leaks. Check transmission
for proper oil level and adjust if necessary.
FIGURE 2-8. TRANSMISSION FILTER

1. Head Assembly 6. Pressure Switch
2. Core Kit 7. Drain Plug
3. Bypass Valve 8. O-Ring
4. Filter Bowl 9. Seal
5. Filter Element

PERIODIC REPLACEMENT OF COMPONENT PARTS FOR SAFETY DEVICES
To ensure safety in operation, the user is requested to perform the periodic maintenance re commended in the previous
schedules. In addition, special care should be paid to the periodic replacement of certain other parts which may affect
safety in operation.
Fabrication of safety devices and other component parts have been designed to high standards. However, all parts
are subject to wear and gradual fatigue during continuous use. Since it is difficult to determine accurately the process
of change in quality, wear, or fatigue, judgements must be made whether or not some parts should be replaced even
if they do not show any faulty symptom at the time. Of course, any part found to have an abnormal ity should be
repaired or replaced, regardless of the time it has been used.
NOTE: This recommendation for the replacement of parts is to ensure safety in operation. Th e warranty
guarantee to be free from manufacturing defects does not apply to the replacement of functioning parts for
precautionary reasons.
The following parts should be considered for repair or The following parts should be considered for repair or
replacement every 2000 hours, or every one year, replacement every 4000 hours, or every two years,
whichever comes first: whichever comes first:
1. Fuel Pump Screen Filter - Check and clean or
1. Brake valve parts. replace screen filter.
2. Parking brake valve parts. 2. Periodic Replacement Safety Parts Kit - Use the
periodic replacement safety parts service kit when
3. Relay valve parts.
replacing the parts.
4. Air governor parts.
3. High pressure hoses in steering circuit (to/from
5. Retarder control valve parts. pump, demand valve, steering valve, steering cyl-
inder). *
6. Emergency relay valve parts.
4. Outlet hose of retarder cooling oil pump. *
7. Emergency brake valve parts.
5. Outlet hose of steering oil pump. *
8. Quick release parts.
6. Outlet hose of transmission oil pump. *
9. Parking brake chamber parts.
7. Steering valve hose. *
10. Brake chamber parts (front and rear).
8. Hose of fuel filter. *
11. Engine Valve Clearance
Refer to the engine manual for the proper inspec- 9. Fuel hose. *
tion, procedures, and tools.
12. Brake Discs - Refer to Section “J”, Brake System, * The replacement of these parts may be
“Brake Circuit Checkout And Adjustment”, for considered for Fire Prevention measures.
proper inspection, procedures and tools.
Other areas of the truck also require inspection and may require periodic replacement of parts due to environmental
and operating conditions. Rubber or plastic parts which are subjected to extreme heat or ul traviolet (sunlight)
conditions will deteriorate more rapidly than similar parts in less severe service.
Periodically check the following:
1. Air inlet piping elbows close to turbochargers and 5. Windshield washer bottle.
exhaust manifolds.
6. Plastic covers and caps.
2. Air cleaner plastic bonnets.
7. Water piping elbows and hoses.
3. Door seals.
8. Body cushion pads.
4. Windshield wiper blades.
9. Plastic tubing for air lines.

NOTES

SECTION Q
ALPHABETICAL INDEX
A C
Cab . . . . . . . . . . . . . . . . . . . . . . N2-1
Accelerator Pedal . . . . . . . . . . . . . . D3-10 Center Case Assembly (Rear Axle) . . . . . . G5-1
AISS Operation . . . . . . . . . . . . . . . D3-11 Charging Procedure
Air Cleaner . . . . . . . . . . . . . . . . . . . C5-1 Suspension . . . . . . . . . . . . . . . . . H4-2
Air Cleaner Indicator . . . . . . . . . . . . . . N3-3 Compressor, Air . . . . . . . . . . . . . . . . . K3-1
Air Compressor . . . . . . . . . . . . . . . . K3-1 Converter, Pressure . . . . . . . . . . . . . . J3-4
Air Conditionioning System . . . . . . . . . . M9-1 Cooling System . . . . . . . . . . . . . . . . C3-1
Component Service . . . . . . . . . . . . . M9-7 Crossover Valve
Air Dryer . . . . . . . . . . . . . . . . . . . . K2-2 Description . . . . . . . . . . . . . . . . . . L4-3
Air Filtration System . . . . . . . . . . . . . . C5-1 Cylinders
General Service Information . . . . . . . . . C5-1 Hoist . . . . . . . . . . . . . . . . . . . . . . L8-4
Air Governor . . . . . . . . . . . . . . . . . . K3-1 Steering
Adjustment . . . . . . . . . . . . . . . . . . K3-2 Removal . . . . . . . . . . . . . . . . . . G3-5
Air Intake Troubleshooting . . . . . . . . . . . C5-4 Disassembly . . . . . . . . . . . . . . . . . L6-1
Air System . . . . . . . . . . . . . . . . . . . K2-1 A-Frame . . . . . . . . . . . . . . . . . . G3-4
Air Governor . . . . . . . . . . . . . . . . . K3-1
Main Air Tank . . . . . . . . . . . . . . . . . K2-1 D
Safety Valve . . . . . . . . . . . . . . . . . K2-1 Decals (Warnings & Cautions) . . . . . . . . . A4-1
Electronic Transmission Control . . . . . . . . D5-1 Decks . . . . . . . . . . . . . . . . . . . . . .B2-1
Alternator, 24VDC . . . . . . . . . . . . . . . D2-3 Demand Valve . . . . . . . . . . . . . . . . . L4-4
Antifreeze Recommendations . . . . . . . . . P2-1 Removal . . . . . . . . . . . . . . . . . . . L6-7
Installation . . . . . . . . . . . . . . . . . . L6-7
Differential Carrier . . . . . . . . . . . . . . G5-5
B Drivelines . . . . . . . . . . . . . . . . . . . . F5-1
Batteries . . . . . . . . . . . . . . . . . . . . D2-1 Dryer, Air . . . . . . . . . . . . . . . . . . . . K2-2
Maintenance and Service . . . . . . . . . . D2-1 Dump Body . . . . . . . . . . . . . . . . . . . B3-1
Troubleshooting . . . . . . . . . . . . . . . D2-2
Battery Charging System . . . . . . . . . . . D2-3
Operation . . . . . . . . . . . . . . . . . . . D2-3
Belt, Fan . . . . . . . . . . . . . . . . . . . . C3-5
Body, Dump . . . . . . . . . . . . . . . . . . B3-1
Body Guide . . . . . . . . . . . . . . . . . . . B3-4
Body Pad . . . . . . . . . . . . . . . . . . . . B3-3
Brake Circuit . . . . . . . . . . . . . . . . . . J2-1
Brake Cooling Valve . . . . . . . . . . . . . J2-15
Bleeding Procedure
Front . . . . . . . . . . . . . . . . . . . . J4-3
Rear . . . . . . . . . . . . . . . . . . . . J4-3
Brake, Parking . . . . . . . . . . . . . . . . . J7-1
Brake Treadle Valve Operation . . . . . . . J2-18
Brake Treadle Valve Repair . . . . . . . . . . J3-1
Q01025 Alphabetical Index Q1-1

H
E Heater . . . . . . . . . . . . . . . . . . . . . N4-3
Electrical System Schematic . . . . . . . . . . R1-1 Blower & Core . . . . . . . . . . . . . . . . N4-4
Electronic Accelerator Pedal . . . . . . . . . D3-10 Hoist Circuit . . . . . . . . . . . . . . . . . . L7-1
Engine . . . . . . . . . . . . . . . . . . . . .C4-1 Hoist Cylinders . . . . . . . . . . . . . . . . L8-4
Engine Specifications . . . . . . . . . . . . . . A2-3 Hoist Circuit Relief Valve . . . . . . . . . . . L7-1
Emergency Steering System . . . . . . . . . L4-12 Hoist Valve . . . . . . . . . . . . . . . . . . L8-1
Hood . . . . . . . . . . . . . . . . . . . . . . B2-1
F Hub, Wheel . . . . . . . . . . . . . . . . . . G3-1
Fan . . . . . . . . . . . . . . . . . . . . . . .C3-4 Suspensions
Belt . . . . . . . . . . . . . . . . . . . . . .C3-5 Front . . . . . . . . . . . . . . . . . . . . . H2-1
Filters Rear . . . . . . . . . . . . . . . . . . . . . H3-1
Engine Air Cleaner . . . . . . . . . . . . . . C5-1 Oil and Nitrogen Specifications . . . . . . . H4-1
Hydraulic . . . . . . . . . . . . . . . . . . . L3-3 Hydraulic,
Transmission . . . . . . . . . . . . . . . . F2-34 Filters . . . . . . . . . . . . . . . . . . . . L3-3
Final Drive Attachment . . . . . . . . . . . . G4-1 Pump . . . . . . . . . . . . . . . . . . . . . L3-1
Removal . . . . . . . . . . . . . . . . . G6-2 Schematic . . . . . . . . . . . . . . . . . . R1-1
Installation . . . . . . . . . . . . . . . . . G6-3 Tank . . . . . . . . . . . . . . . . . . . . . L3-2
Repair . . . . . . . . . . . . . . . . . . . G6-3
Front Suspension . . . . . . . . . . . . . . . . H2-1 I
Front Wheel Brakes . . . . . . . . . . . . . . . J5-1 Instrument Panel & Controls . . . . . . . . . . N5-1
Front Wheel Brake Cut Out . . . . . . . . . . J2-14
Front Wheel Hub and Spindle . . . . . . . . G3-1 L
Front Tires & Rims . . . . . . . . . . . . . . G2-2
Lubrication and Service . . . . . . . . . . . . P2-1
Fuel Tank . . . . . . . . . . . . . . . . . . . . B4-1
Lubrication Chart . . . . . . . . . . . . . . . P2-2
G M
General Safety Rules . . . . . . . . . . . . . . A3-1
Main Air Schematic . . . . . . . . . . . . . . R1-1
Governor, Air . . . . . . . . . . . . . . . . . . K2-1
Metric Conversion . . . . . . . . . . . . . . . A5-1
Grille . . . . . . . . . . . . . . . . . . . . . . B2-1
Q1-2 Alphabetical Index Q01025

N S
Nitrogen Specifications . . . . . . . . . . . . . H4-1 Safety Rules . . . . . . . . . . . . . . . . . . A3-1
Safety Valve (Air) . . . . . . . . . . . . . . . . K2-1
O Seat . . . . . . . . . . . . . . . . . . . . . . N4-1
Oil Cooler, Transmission . . . . . . . . . . . . F3-1 Service Capacities . . . . . . . . . . . . . . . P2-1
Oil Specification (Suspension) . . . . . . . . . H4-1 Special Tools . . . . . . . . . . . . . . . . . M8-1
Oil Strainer, Transmission . . . . . . . . . . . F3-1 Specifications
Oiling and Charging Procedure . . . . . . . . H4-1 Oil, Suspension . . . . . . . . . . . . . . . H4-1
Operating Instructions . . . . . . . . . . . . A3-17 Nitrogen . . . . . . . . . . . . . . . . . . . H4-1
Operator Controls . . . . . . . . . . . . . . . N5-1 Lubrication Chart . . . . . . . . . . . . . . . P2-2
Optional Equipment . . . . . . . . . . . . . . M-1 Truck . . . . . . . . . . . . . . . . . . . . . A2-3
Spindle, Front Wheel Hub . . . . . . . . . . G3-1
Steering
Column . . . . . . . . . . . . . . . . . . . N5-11
P Circuit Test Procedure . . . . . . . . . . . L10-4
Diagonial Panhard Rod . . . . . . . . . . . . G4-2 Control Valve . . . . . . . . . . . . . . . . . L5-1
Parking Brake . . . . . . . . . . . . . . . . . J7-1 Cylinders . . . . . . . . . . . . . . . . . . . L6-2
Payload Meter . . . . . . . . . . . . . . . . M20-1 Troubleshooting . . . . . . . . . . . . . . L10-10
Pedal Suspension
Accelerator . . . . . . . . . . . . . . . . . D3-10 Front . . . . . . . . . . . . . . . . . . . . . H2-1
Bra . . . . . . . . . . . . . . . . . . . . . N5-2 Rear . . . . . . . . . . . . . . . . . . . . . H3-1
Throttle . . . . . . . . . . . . . . . . . . . . N5-2
Retarder . . . . . . . . . . . . . . . . . . . N5-2
Planetaries . . . . . . . . . . . . . . . . . . . G6-1 T
Plates, Warning and Caution . . . . . . . . . . A4-1 Tank
Pressure Converter . . . . . . . . . . . . . . J3-4 Air . . . . . . . . . . . . . . . . . . . . . . .K2-1
Pump, Hydraulic . . . . . . . . . . . . . . . . L3-1 Fuel . . . . . . . . . . . . . . . . . . . . . .B4-1
Hydraulic . . . . . . . . . . . . . . . . . . . L3-2
R Throttle Control
Radiator . . . . . . . . . . . . . . . . . . . . C3-1 Pedal . . . . . . . . . . . . . . . . . . . . D3-10
Range Selector Console . . . . . . . . . . . . N5-3 Throttle Position Sensor . . . . . . . . . . . D3-10
Rear Suspension . . . . . . . . . . . . . . . . H3-1 Tie Rod . . . . . . . . . . . . . . . . . . . . G3-5
Rear Tire and Rim . . . . . . . . . . . . . . . G2-3 Tires
Rims . . . . . . . . . . . . . . . . . . . . . . G2-4 Front . . . . . . . . . . . . . . . . . . . . . G2-2
Rock Ejector . . . . . . . . . . . . . . . . . . B3-4 Rear . . . . . . . . . . . . . . . . . . . . . G2-3
Rod, Tie . . . . . . . . . . . . . . . . . . . . G3-5 Tools, Special . . . . . . . . . . . . . . . . . M8-1
Q01025 Alphabetical Index Q1-3

Torque Table (Standard) . . . . . . . . . . . . A5-2 Heater Control . . . . . . . . . . . . . . . . N4-3
Torque Converter . . . . . . . . . . . . . . . . F2-2 Hoist . . . . . . . . . . . . . . . . . . . . . L7-1
Towing . . . . . . . . . . . . . . . . . . . . A3-28 Hoist Circuit Relief . . . . . . . . . . . . . . L10-4
Transmission . . . . . . . . . . . . . . . . . F2-15 Parking Brake . . . . . . . . . . . . . . . . J7-1
Transmission Filters . . . . . . . . . . . . . F2-34 Safety (Air) . . . . . . . . . . . . . . . . . . K2-1
Troubleshooting Service Brake Treadle . . . . . . . . . . . . J3-1
Air Intake . . . . . . . . . . . . . . . . . . . C5-4 Steering Control (Hydraulic) . . . . . . . . . L5-1
Battery . . . . . . . . . . . . . . . . . . . . D2-1 Wiper Control . . . . . . . . . . . . . . . . N3-1
Electrical System . . . . . . . . . . . . . . . D4-1
Monitor Panel . . . . . . . . . . . . . . . . . D6-1 W
Steering Circuit . . . . . . . . . . . . . . L10-10
Warnings and Cautions . . . . . . . . . . . . A4-1
Steering Control Valve . . . . . . . . . . . . L4-2
Weights (Truck) . . . . . . . . . . . . . . . . A2-4
Transmission . . . . . . . . . . . . . . . . . D5-1
Wheel Cylinder, Brake
Front . . . . . . . . . . . . . . . . . . . . . J5-2
V Rear . . . . . . . . . . . . . . . . . . . . . J6-1
Valves Wheel Hub and Spindle . . . . . . . . . . . . G3-1
Automatic Emergency Relay . . . . . . . . J2-13 Wheels and Tires
Brake Cooling Valve . . . . . . . . . . . . J2-15 Front . . . . . . . . . . . . . . . . . . . . . G2-2
Crossover . . . . . . . . . . . . . . . . . . . L4-3 Rear . . . . . . . . . . . . . . . . . . . . . G2-3
Demand . . . . . . . . . . . . . . . . . . . L4-2 Windshield Washer . . . . . . . . . . . . . . N3-2
Emergency Brake . . . . . . . . . . . . . . J2-16 Windshield Wiper . . . . . . . . . . . . . . . N3-1
Emergency Relay (RE6) . . . . . . . . . . . J2-2
Q1-4 Alphabetical Index Q01025

SECTION R
SYSTEM SCHEMATICS
INDEX
AIR SYSTEM PIPING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HA204
AIR SYSTEM SCHEMATIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HA203
HYDRAULIC SYSTEM SCHEMATIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HH339
HYDRAULIC SYSTEM PIPING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HH340
TRANSMISSION CROSS SECTION VIEW . . . . . . . . . . . . . . . . . . . . . . . . . . KT-T01
ELECTRICAL WIRING SCHEMATIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HE462
R01031 02/ Schematics R1-1

NOTES
R1-2 Schematics R01031 02/

HE462 TABLE OF CONTENTS (330M)
-A- LOCATION -D- LOCATION
ACCELERATOR SENSOR 112 DASH LIGHTS 28, 29
AIR CONDITIONER COMPRESSOR 39 DASH LIGHT DIMMER 29
AIR CONDITIONER CONTROL LIGHT 39 DISPLAY MODE CHANGE SWITCHES (1 & 2) 103
AIR CONDITIONER HIGH PRESSURE SWITCH 38 DOME LIGHT DOOR SWITCH 19
AIR CONDITIONER LOW PRESSURE SWITCH 39 -E-
AIR CONDITIONER SWITCH 39, 40 ELECT. CONTROL MOD. VALVE (ECMV) SOLENOID 87, 88
AIR DRYER HEATER 56 EMERGENCY BRAKE SWITCH 20
AIR PRESSURE SENSOR 73 EMERGENCY STEERING INDICATOR LIGHT 47
AISS SWITCH 66 EMERGENCY STEERING MONITOR LIGHT 60
ALTERNATOR 3 EMERGENCY STEERING MOTOR & PUMP ASSEMBLY 48
ALTERNATOR CHARGE MONITOR LIGHT 60 EMERGENCY STEERING RELAYS 5, 48
-B- EMERGENCY STEERING RELAY SWITCHES 48
BT1-1 RADIO, RADIO CONVERTOR 70 EMERGENCY STEERING SWITCH 47
BT1-2 HORN 17 EMERGENCY STEERING TIMER RELAY 45
BT1-3 CIGAR LIGHTER 13 ENGINE CONTROLLER 108, 109
BT1-4 TURN SIGNALS AND FOG LIGHTS 14 ENGINE HEATER TIMER 12
BT1-5 NEUTRAL START 10 ENGINE MONITOR LIGHTS 105, 106
BT1-6 STOPLIGHT, HDLAMP LOW BEAM, DOME LIGHT 19 ENGINE OIL PRESSURE MONITOR LIGHT 61
BT1-7 CLEARANCE LAMP, HEADLAMP HIGH BEAM 28 ENGINE SPEED SENSOR 110
BT1-8 BACK-UP LIGHTS & ALARM 26 EXHAUST BRAKE MONITOR LIGHT 28
BT1-9 ENGINE HEATERS, FRONT BRAKE CUT-OFF, 12, 18 EXHAUST BRAKE SWITCH 37
BRAKE CONTROL VALVE (BCV), COLD START -F-
BT1-10 SHIFT INDICATOR, TRANS. CONTROLLER, 36, 68 FLASHER 15
EXHAUST BRAKE OPTION
FAULT CHECK SWITCH (ENGINE) 106
BT2-1 ENGINE CONTROLLER 14
FAULT CODE SWITCH (ENGINE) 106
BT2-2 INSTRUMENT PANEL, MONITOR LAMP, 41, 60
WARNING LAMP BUZZER FLOW SWITCH 44
BT2-3 AUTOMATIC SUSPENSION CONTROLLER 51 FOG LIGHTS 16
BT2-4 PAYLOAD METER 53 FOG LIGHT SWITCH CONNECTOR 15
BT2-5 PAYLOAD METER 53 FRONT BRAKE CUT-OFF SOLENOID 18
BT2-6 PAYLOAD METER LAMP 6 FRONT BRAKE CUT-OFF SWITCH 18
BT2-7 TURN SIGNAL & FOG LIGHTS 7, 15 FUEL LEVEL SENSOR 54
BT2-8 BATTERY DIRECT 8, 81, 109, 115 FU - FUSE, 30 AMP 6
BT2-9 EMERGENCY STEERING 7, 45 -H-
BT2-10 AIR DRYER HEATER 7, 55 HAZARD SWITCH 15
BT3-1 NOT USED HEATER, ENGINE 3
BT3-2 WASHER MOTOR, WIPER MOTOR 57 HIGH BEAM LEVER 29
BT3-3 AIR CONDITIONER BLOWER 38 HORN BUTTON 17
BT3-4 AIR CONDITIONER COMPRESSOR 38 HORN SOLENOID 17
BT3-5 NOT USED -I-
BT3-6 NOT USED INSTRUMENT PANEL HOURMETER LAMP 29
BACK-UP LIGHT 26 INSTRUMENT APNEL ODOMETER LAMPS 29
BACK-UP HORN 27 INTERMITTENT WIPER RELAY 58
BATTERIES 4 -K-
BATTERY GROUND 45 KEY SWITCH 7
BATTERY RELAY SWITCHES 5 -L-
BCV SOLENOID 23 LADDER (ENGINE SHUTDOWN SWITCH) - OPTIONAL 107
BLOWER SWITCH 40 LEFT FRONT TURN SIGNAL 13
BODY FLOAT MONITOR LIGHT 60 LEFT HEADLAMP HIGH BEAM 31
BODY FLOAT SWITCH 66 LEFT HEADLAMP LOW BEAM 32
BRAKE STROKE SENSOR 50 LEFT REAR TAIL LIGHT 33
BRAKE STROKE MONITOR LIGHT 61 LEFT REAR TURN SIGNAL 13
-C- LEFT SIDE CLEARANCE LAMP 32
CENTER TAIL LIGHT 33 LEFT SIDE WORK LAMP 32
CHARGE MONITOR LIGHT 60 LEFT SPEAKER 72
CIGAR LIGHTER 13 -M-
COLD START MONITOR LAMP 28 MAINTENANCE CAUTION MONITOR LIGHT 62
COLD START SWITCH 12 MONITOR PANEL LAMP TEST SWITCH 64
COOLANT LEVEL WARNING LIGHT 61
-P- LOCATION -T- LOCATION
PARK BRAKE MONITOR LIGHT 60 TACHOGRAPH 30
PARK BRAKE PRESSURE SWITCH 44 TILT CAUTION MONITOR LIGHT 61
PARK BRAKE RELAY 45 TORQUE CONVERTER OIL TEMPERATURE SENSOR 87
PAYLOAD METER LOAD LIGHT RELAYS 52, 53 TORQUE CONVERTER LOCKUP SOLENOID 87, 88
POWER MODE SWITCH 34 TRANSMISSION FILTER MONITOR LIGHT 60
POWER TRAIN MANAGEMENT CONTROLLER (PMC) 113 - 120 TRANSMISSION OIL TEMPERATURE SENSOR 87
(OPTIONAL) TRANSMISSION RANGE SELECTOR 79, 80
PRE-LUBE OIL PRESSURE SWITCH 1 TRANSMISSION RANGE SELECTOR LIGHT 31
PRE-LUBE TIMER SOLENOID 1 TRANSMISSION SHAFT SPEED SENSOR 87, 88
-R- TURN SIGNAL SWITCH 15
R01 START RELAY 10 -W-
R02 NEUTRAL RELAY 11 WARNING BUZZER 100, 101
R03 SERVICE BRAKE RELAY 20 WARNING LIGHT 100, 101
R04 BCV RELAY 23 WASHER MOTOR 57
R05 BACK-UP ALARM RELAY 26 WIPER MOTOR 59
R06 HEADLIGHT RELAY (HIGH BEAM) 31 WIPER SWITCH 59
R07 CLEARANCE LAMP RELAY 29
R08 HEADLIGHT RELAY (LOW BEAM) 32
R09 REAR BRAKE RELAY 24 ADDITIONS / CHANGES
R-11 PAYLOAD METER RELAY 53
R-15 FOG LIGHT RELAY (OPTIONAL) 16
R-18 PAYLOAD METER LIGHTS (AMBER) 52, 53
R-19 PAYLOAD METER LIGHTS (RED) 52, 53
R-20 PAYLOAD METER LIGHTS (GREEN) 52, 53
R-21 PARK BRAKE RELAY 45
R-25 TRANSMISSION SOLENOID OFF RELAY 75
R-26 HAZARD RELAY (1) 14
R-27 HAZARD RELAY (2) 14
RADIO 71
RADIO CONVERTER 71
REAR BRAKE INDICATOR LIGHT 24
REAR BRAKE MONITOR LIGHT 28
RELAY, HEATER - ENGINE 2
RETARDER BRAKE SWITCH 19
RETARDER OIL TEMPERATURE SWITCH 84
RIGHT FRONT TURN SIGNAL 15
RIGHT HEADLAMP HIGH BEAM 31
RIGHT HEADLAMP LOW BEAM 32
RIGHT REAR TAIL LIGHT 34
RIGHT REAR TURN SIGNAL 15
RIGHT SIDE CLEARANCE LAMP 34
RIGHT SIDE WORK LAMP 35
RIGHT SPEAKER 71
-S-
S - NET SIGNALS CHART 103, 104
SAFETY RELAY 1 1
SAFETY RELAY 2 2
SERVICE BRAKE SWITCH 20
SHIFT LIMIT SWITCH 76, 77
STARTER MOTORS 1
STEERING OIL TEMPERATURE 63
STOP LAMP (CENTER) 21
STOP LAMP (LEFT) 21, 24
STOP LAMP (RIGHT) 21, 24
SUSPENSION CONTROLLER (OPTIONAL) 121 - 128
Komatsu Mining Systems, Inc.
Peoria Operations, P.O. Box
Peoria, IL 61650-
U.S.A.
Printed in U.S.A.

330M Komatzu PDF

Uploaded by

Copyright:

Available Formats

330M Komatzu PDF

Uploaded by

Document Information

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

330M Komatzu PDF

Uploaded by

Copyright:

Available Formats

DG728

330M A10190 Thru

This material is proprietary to Komatsu Mining Systems, Inc. and is not

A00019 Introduction A-1

“DANGER” identifies a specific potential hazard

“WARNING” identifies a specific potential hazard

“CAUTION” is used for general reminders

A-2 Introduction A00019

ENGINE, FUEL, COOLING AND AIR CLEANER . . . . . . . . . . . . . . . . . . . . . . . . . C

ELECTRIC SYSTEM (24 VDC. NON-PROPULSION) . . . . . . . . . . . . . . . . . . . . . . D

TRANSMISSION AND TORQUE CONVERTER . . . . . . . . . . . . . . . . . . . . . . . . . F

DRIVE AXLE, SPINDLES AND WHEELS . . . . . . . . . . . . . . . . . . . . . . . . . . . G

OPTIONS AND SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M

LUBRICATION AND SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P

A00019 Introduction A-3

A-4 Introduction A00019

TRUCK COMPONENT DESCRIPTION & SPECIFICATIONS . . . . . . . . . . . . . . . . A2-1

GENERAL SAFETY AND TRUCK OPERATION . . . . . . . . . . . . . . . . . . . . . . . A3-1

WARNINGS AND CAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A4-1

CHARTS AND TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A5-1

STANDARD MAINTENANCE VALUES . . . . . . . . . . . . . . . . . . . . . . . . . . . A6-1

A01004 Index A1-1

A1-2 Index A01004

ENGINE POWER STEERING

A02039 Major Components and Specifications A2-1

A2-2 Major Components and Specifications A02039

A02039 Major Components and Specifications A2-3

TIRES EMPTY . . . . . . . . Kilograms . . . Pounds

OVERALL TRUCK DIMENSIONS

OVERALL TRUCK DIMENSIONS

A2-4 Major Components and Specifications A02039

Read and follow all safety precautions. Failure to do so may result

CLOTHING AND PERSONAL PROTECTIVE ITEMS

A03011 4/98 General Safety and Operating Instructions A3-1

MOUNTING AND DISMOUNTING

FIRE PREVENTION FOR FUEL AND OIL

A3-2 General Safety and Operating Instructions A03011 4/98

ASBESTOS DUST HAZARD PREVENTION

PREVENTION OF INJURY BY WORK EQUIPMENT

FIRE EXTINGUISHER AND FIRST AID KIT

• Provide a first aid kit at the storage point.

A03011 4/98 General Safety and Operating Instructions A3-3

PRECAUTIONS FOR ATTACHMENTS

A3-4 General Safety and Operating Instructions A03011 4/98

BEFORE STARTING ENGINE

VENTILATION FOR ENCLOSED AREAS

A03011 4/98 General Safety and Operating Instructions A3-5

A3-6 General Safety and Operating Instructions A03011 4/98

WHEN STARTING ENGINE

CHECK WHEN TRAVELING IN REVERSE

A03011 4/98 General Safety and Operating Instructions A3-7

OPERATE CAREFULLY ON SNOW

AVOID DAMAGE TO DUMP BODY

DO NOT GO CLOSE TO HIGH-VOLTAGE CABLES

Voltage Min. Safety Distance

• The following actions are effective in preventing accidents:

A3-8 General Safety and Operating Instructions A03011 4/98

WORKING ON LOOSE GROUND

PARKING THE MACHINE