BWM E46 Complete Vehicle Description
BWM E46 Complete Vehicle Description
BWM E46 Complete Vehicle Description
Table of Contents
E46 MODELS
Subject Page
E46/4 Sedan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
E46/2 Coupe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Body
Body Shell. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Hood and Headlights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Doors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Door Anchoring System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Door Handles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Sunroof. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Interior Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Driver Information Displays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Seats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Power Distribution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Front Suspension. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Rear Suspension. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Final Drive. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Brake System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Interior. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Subject Page
Rear Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Center Arm Rest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Child Seat Restraint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Cargo Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Emergency Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Rear Window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Technical Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Body Shell
Floor Pan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Windshiel Frame. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Rear Bulkheads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Tension Strut. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Aluminum Support Plate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Rear Seats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Variable Top Storage Compartment. . . . . . . . . . . . . . . . . . . . . . . .43
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Chassis
Front Axle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Steering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Differential and Front Axles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Rear Axle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Tires and Wheels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Transmissions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Transfer Case. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
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Objectives:
3
E46 Models
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E46/4 Sedan
The E46 is the successor to the E36 and is the next evolution in the 3 series development.
The E46/4 Sedan was introduced as a 1999 model as both the 323i and 328i.
The E46 3 series vehicle offers more comfort, safety, space and equipment than the previ-
ous E36, without compromising the sporty characteristics of the 3 series vehicle.
Since start of production,two engine variants have been offered, the M52TU and the M54
six cylinders. Both engines introduced changes and design improvements that will be cov-
ered in the Engine and Engine Management chapters.
4
E46 Models
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E46/4 Dimensions
5
E46 Models
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E46/2 Coupe
The E46/2 Coupe was introduced as a 2000 model year vehicle in both 323Ci and 328Ci
variants.
The body of the E46 /2 Coupe is not a modified sedan, but is a completely distinct body.
There are no sheet metal parts shared between the Sedan and the Coupe Only the design
technology of the E46/4 was used to create the E46 Coupe. The Coupe is even longer and
wider than the sedan.
The E46 Coupes have been given the “Ci” (coupe injected) trunk badge designation. This
is a departure from the “is” (injected sport) from previous 3 series coupes.
Since start of production,two engine variants have been offered, the M52TU and the M54
six cylinders. Both engines introduced changes and design improvements that will be cov-
ered in the Engine and Engine Management chapters.
6
E46 Models
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E46/2 Dimensions
7
E46 Models
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Body
Body Shell
The structural rigidity of the E46 body shell was increased using computer aided design
(CAD) techniques. Every component of the new body structure was designed using this
method. CAD allows the design to be translated into computer aided manufacturing (CAM)
more efficiently. To reduce the weight of the vehicle, while retaining strength, high strength
steels are used and now amount to 50% of the body shell weight.
The second area of focus of the body shell is "structural dynamics". This deals with vibra-
tion frequencies that effect the ride quality and rigid feel. The E46 body shell was designed
so that the frequencies for torsional twisting and bending are separated and are in an
inaudible range. The ranges match the E39 for twisting at 29 hertz and bending at 26 hertz.
The E46 continues with BMW’s safety cage concept for passenger protection. The tubular
impact structures continue to provide protection against body damage during front or rear
impacts.
The E46 is 1.8 times more able to absorb energy in a 40mph offset frontal crash than the
E36.
8
E46 Models
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The hood is opened by first pulling the release lever located inside the vehicle and then
releasing the secondary catch that pops out of the grille.
The E46 carries on with the traditional four head lamp configuration, however, no internal
lens is used over each lamp. The free-form reflectors are clearly visible through the smooth,
plastic covers. The plastic covers are lighter in weight and more resistant to breakage than
the previous glass covers.
Vertical and horizontal adjustments for the head lamps are located on the upper rear edge
of the assemblies.
Xenon low beam head lamps will be an available option starting with 9/98 production.
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E46 Models
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Doors
The doors on the E46 feature the door anchoring system introduced with the E38. The
anchor consists of a horizontal bar in the door and a hook at the rear edge. The hook rests
in a recess in the "B" and "C" pillars and it reinforces the body in the event of a side impact.
The door seal design is copied from the E39 and is a single piece seal.
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E46 Models
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E46 Models
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Door Handles
The door handles and locking system on the E46 are of a new design. The new bow type
handles allow the doors to be opened easier. The locks are fully encapsulated including the
electrical components. The new door handle/latch/lock assembly offers improved reliability
and security against theft. The micro-switches for door position and lock condition have
been replaced by hall sensors.
There are no serviceable components on the lock assembly and it must be replaced as a
unit.
From September 2000 production, there was a modification done to the door handles of
the E46. The modified door handles when pulled, fold upward instead of straight out as
previous. The lock assembly was also modified to accommodate the new articulation of
the door handles.
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E46 Models
Sunroof
The sunroof design is similar to the E38/E39, however, the sunroof cassette is not service-
able and must be replaced as a complete unit. The sunroof is an option on the E46 and will
come with a glass panel (moon roof) instead of a steel panel.
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E46 Models
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Interior Features
The interior of the E46 has been completely redesigned with an emphasis on more space,
luxury and convenience without compromising the 3 series sporty characteristics.
The new instrument panel/dash is similar in design to the E39 with a slightly less pro-
nounced orientation to the driver. The E38/E39 type face vent grills are used for air distrib-
ution.
The multi-function steering wheel is available on both the 323/325 models and standard
on 328/330 models. There are two different steering wheels available, the four spoke wheel
with MFL and a three spoke sport wheel with MFL. The three spoke sport wheel is option-
al for sedans and standard in coupes. The MFL includes the controls for the audio system
on the left and the cruise control on the right.
The E46 comes equipped with a manually adjustable (tilt/telescopic) steering column. There
is 30 mm of vertical and horizontal adjustment for the steering column.
1. Spring
2. Clamping mechanism
3. Steering lock with
steering column tube
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E46 Models
Driver information Displays
The primary display for driver information is located in the instrument cluster. The coupe and
sedan have different cluster lettering and faces. The secondary display in the console con-
sists of the audio system and automatic climate control panel (if equipped with IHKA).
80 3 4
60 100
100
120 140
160
2 1/min
x1000
5
80 180 120
40
12 60 200 1 6
11 40 220
0
20 20 240 140
UNLEADED GASOLINE ONLY 0 50 30 20 15 7
km/h 12
MPH
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E46 Models
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Seats
The front seats are similar in design to the E36 seats with new internal construction to
improve their support and comfort. Memory for the drivers seat position is available. The
seat controls, including memory storage buttons are located on the side of the seat base.
An optional lumbar support is also available for the E46.
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E46 Models
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A split folding (40/60) seat is available as an option on sedans and standard on coupe
models.
The release for the folding seat backs is located in the trunk on the left and right sides near
the wheel arches. This increases the security aspect when keeping items locked in the
trunk.
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E46 Models
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Power Distribution
The battery is installed in the trunk of the E46 and features lead/calcium plate material for
true maintenance free operation. The water usage of this battery is low throughout its ser-
vice life.
The Battery Safety Terminal is installed at the positive terminal of the battery. A repair kit is
available for the BST.
The E46 is produced with a vehicle specific wiring harness. This harness is based on the
ordered optional equipment of the vehicle so that it contains the proper connectors and
connections. Options can not be added at a later time without replacing the entire harness.
Specific kits are available to repair the harness in the event of an accident or damage to the
harness. These repair kits include:
• Engine compartment
• Vehicle’s rear area
If the entire harness need to be replaced, a new harness with the maximum equipment or
options must be ordered. This is the only harness that will be stocked in the parts system.
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E46 Models
There are three locations for fuses on the E46:
The E46 uses high amperage fuses for circuit protection. The battery power supply is pro-
tected by a 250 amp fuse in the trunk.
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E46 Models
Front Suspension
The single ball joint, strut axle of the E46 is based on the E36 design. Design and compo-
nent changes were developed to improve the ride quality and handling characteristics. The
following changes are incorporated into the E46 front suspension system:
• A new forged aluminum control arm is used on the E46 (except all-wheel drive). It offers
the advantages of weight reduction and lower unsprung mass.
• Hydraulic bushings are used for the rear lower control arm support.
• The steering knuckles are press fit into the strut tubes which reduces the tolerances of
the front suspension geometry.
Altogether there is 5.72 lbs less unsprung weight in the front suspension which enhances
ride comfort and handling.
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E46 Models
Front Camber Adjustment
The top of the strut is mounted through elongated holes. The strut is fixed in position when
the vehicle is assembled. If minor corrections need to be made to the front end alignment,
the pin can be driven down and the strut can be moved in the slots to adjust the camber.
Approximately .5o of adjustment is available by moving the strut in the slots.
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E46 Models
Rear Suspension
The design of the E46 rear suspension is based on the E36 "C" arm type. However, all
components of the suspension are new and designed to suit the E46 for:
The sub frame is a new design employing steel tubes and metal sections. It is more rigid
than the previous sub frame. This provides a stable platform for the rear suspension to
work from. The differential is mounted to the sub frame using a hydraulic mount. The sub
frame is mounted to the body at four vibration absorbing rubber mounts.
The upper transverse control arms are made from cast aluminum for weight saving.
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E46 Models
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Final Drive
• Compact housing
• Shorter pinion shaft
• Hollow drive flange shafts
• No side bearing covers
• Elimination of speedometer gear
• Lifetime synthetic oil
The drive shaft and differential are now mounted on the center line of the vehicle. This
enables the transmission tunnel to be narrower increasing the interior passenger space.
With this change, the axle shafts are now different in length and are no longer interchange-
able.
Brake System
The braking system is upgraded for the E46 to match the vehicle’s size and braking require-
ments. The dual circuit (front/back) distribution system continues to be used for optimized
braking response and performance. Refinements to the brake pedal linkage increase the
brake response time to improve braking performance.
The E46 uses a 10" vacuum booster, vented in the engine compartment to reduce noise in
the passenger compartment.
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E46 Models
E46 SPORT WAGON
Model: E46/3
Production: 1/00
Objectives:
• Identify the changes to the body of the E46 for the Sport Wagon.
The E46/3 “Sport Wagon” is being introduced to the US market as a 2001 Model Year vehi-
cle. It joins the highly successful Sedan and Coupe models to further enhance the product
line up and offer 3 series customers an alternative choice of vehicle.
Up to the “B” pillars, the Sport wagon is identical to the E46 sedan. The rear doors have
been remodeled for wagon usage and the tail gate is similar to the E39 Sport Wagon with
an opening rear window.
The rear seats fold down to provide 1345 liters of cargo space. With the seats up, the rear
compartment provides 435 liters of load space.
00E46SPTWGN0400
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E46 Models
BODY SPECIFICATIONS
1471 mm 1478 mm
1739 mm 1932 mm
41E46SPTWGNSPEC0000
The E46 Sport Wagon is 7 mm longer that the sedan and the unloaded height is 6 mm
lower. The wheel base, width and turning radius are the same as the E46 sedan. The fol-
lowing are the maximum cargo capacity/ loads:
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E46 Models
Body
From the front bumper up to the “B” pillar the E46 Sport Wagon body is identical to the
sedan. From the “B” pillar rearward, the body shell of the Sport Wagon is all new and
includes:
The structural rigidity and “structural dynamic” characteristics introduced with the E46
sedan are carried over to the E46 Sport wagon. As with the sedan and coupe, the Sport
Wagon body shell acts as the passenger’s safety cage along with the tubular impact struc-
tures for the front and rear bumper mountings.
41E46SPTWGNREAR00
41E46SPTWGNREAR0100
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E46 Models
Interior
Up to the “B” pillar, the interior equipment and trim level corresponds to the E46 sedan. The
front seat options are the same as the E46 Sedan, while the rear seating area has been
newly designed to provide an attractive package that offers optimum functionality and use-
able space when the seats are folded down for cargo loading.
52E46BACKSEAT0200
The rear seats backs are a 60/40 split with the center arm rest section on the left seat back.
The center passenger’s inertia reel is mounted to the left seat back, while the left/right rear
passenger’s belt reels are mounted on the wheel housings. The lower section of the seat
back is separate foam piece that enables the back rest pivot point to be higher on the seat
back. This allows the back rest to fold flat for more useable cargo loading space.
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E46 Models
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The center arm rest incorporates the non-adjustable center head rest. The center arm rest
is folded down to gain access to the storage compartment and cup holders , which are
integrated into the rear of the head rest.
CUPHOLDER
STORAGE COMPARTMENT
52E46SPTWGNCUP0500
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E46 Models
Child Seat Anchor
There are three child seat hold down anchors positioned behind the rear seat back rest.
The plastic covers must be removed to access the hold down anchors,
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E46 Models
Cargo area
The cargo area offers 435 liters of cargo space with the rear seat back rest raised and 1345
liters with it lowered. The cargo area offers a spring loaded - roller blind and cargo net sim-
ilar to the E39 Sport Wagon.
51E46SPTWGNCARGONET0000
00E46SPTWGNCARGO0500
30
E46 Models
ANTENNA AMPLIFIER
Storage Compartments
Load Floor/Spare
The load floor is removable to access the
OOL KIT SPARE TIRE spare tire and control module mounting
66460001 area located beneath. A strap is provided to
hold the load floor up while accessing the
SOUND SYSTEM WINDOW WASHER storage area. The interior trim panel must
COMPONENTS FLUID RESERVOIR
also be removed for access to the spare
and control modules.
Power Socket
61460001
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E46 Models
Tail gate
The tail gate is similar in design to the E39 Sport Wagon, including the rear glass that is
hinged separately and can be opened independently from the tail gate.
TAILGATE RELEASE
SWITCH
Rear Actuator
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E46 Models
Emergency Release
The tailgate does not feature a lock cylinder so an emergency release mechanism is incor-
porated into the tail gate latch. It allows mechanical opening of the gate actuator in the
event of an electrical failure. The release is located along the lower edge of the rear apron
behind a small access cover. After removing the cover, the lever is pushed to the right to
mechanically release the tail gate.
EMERGENCY RELEASE
The rear apron of the E46 Sport Wagon is lowered for easier loading/unloading. A plastic
rubbing strip prevents the bumper from being scratched when cargo is being
loaded/unloaded.
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E46 Models
Rear Window
The Frameless rear window is bonded to a metal carrier which is hinged to the body. If the
rear window needs replacement, it is supplied with the glass bonded to the metal carrier.
The release switch for opening the rear glass is incorporates into the rear wiper arm cover
under the triangle trim plate.
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E46 Models
Rear Glass Hinge
41460001
63E46SPTWGNTAILLIGHT0000
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E46 Models
E46 Convertible
Model: E46/2C
Production: 01/00
Objectives:
• Identify the floor pan reinforcements for energy absorption on the SGS seats.
• Identify the body shell reinforcements necessary for the addition of the Variable
Convertible Top Storage Compartment Floor.
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E46 Models
Introduction
The E46 Convertible is the replacement for the E36 Convertible and is based on the E46
Coupe. It is initially being introduced in March 2000, as a 323 Model only with the M52 TU
2.5 liter engine. The 3 liter version of the E46iC will begin production starting in 6/2000.
The E46 323 features a new design top that consists of a three layer top and all glass rear
window. The 323 comes with a manual top as standard equipment. The new fully automatic
electro-hydraulic top is available as an option. The 330 E46iC will come with the fully auto-
matic top as standard equipment.
The roll over protection system is standard equipment and is similar in design to the E36
system. The roll over protection bars are hidden by the rear headrest and deployed under
the same criteria as the E36 system.
The front seats of the E46iC are a new design with the seat integrated belt (SGS) system
similar to the system introduced on the E31 - 8 series vehicles.
00E46ICINTRO100
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E46 Models
TECHNICAL DATA
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E46 Models
TECHNICAL DATA
E36 E46
E36 E46
Convertible
Convertible Convertible
Convertible
(323i) (323i)
Length (mm)
Outside Car Dimensions
4433 4488
Width (mm) (with mirror)
Length (mm)
1710 (1875)
4433 4488
1757 (1947)
Height
Width (mm)
(mm) (With Mirrors) 1348(1875)
1710 1757 (1947) 1372
Height (mm) 1648 1672
Shoulder
Inside Room, front (mm)
Car Dimensions 1352 1384
Shoulder
Shoulder Room, rear(mm)
Room, front (mm) 1108
1352 1384 1165
Shoulder
Elbow Room,front
Room, rear (mm)
(mm) 1108
1412 1165 1443
Elbow Room, front (mm) 1412 1443
Elbow
ElbowRoom, rear
Room, rear (mm)
(mm) 1120
1120 1208 1208
Effective headroom, front (mm) 968 974
Effective headroom, front (mm)
Effective headroom, rear (mm)
968
921 937
974
Effective headroom, rear (mm) 921 937
General Information
Cd Cd 0.36
0.36 0.36 0.36
Unladen weight 3319 3516
Unladen weight (lb) 3319auto)
(3396 (3649 auto) 3516
Total Weight (3396
4035auto) 4322 (3649 auto)
(4112 auto) (4410 auto)
Total Weight
Luggage (lb) (L)
Comp. Volume 4035
230 260 4322
(Comp Floor Extended (4112 auto) (300) (4410 auto)
SpeedComp.
Luggage Rating Volume (L) 230 260
(Comp Floor
Top Speed Extended)
(MPH) 128 128 (300)
governed governed
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E46 Models
Body Shell
The body shell of the E46iC has been developed specifically for the convertible to improve
crash performance which is similar to the E46 Coupe. This was achieved by the use of
reinforcements on the body shell that improved torsional rigidity (body twisting). In the main
body floor pan, reinforcements were necessary to accommodate the new SGS (Seat
Integrated Belt System) seat system. In the rear floor pan, reinforcements were necessary
to account for the variable convertible top storage. compartment floor.
ART-E46BODY3
Components
Floor Pan
The floor pan is reinforced to support the SGS seat by heavier cross brace members, rein-
forced tunnel/floor pan and reinforced engine support brackets. During a collision all forces
occurring on the seat are channeled to be absorbed by the floor pan.
Windshield Frame
The windshield frame is reinforced with stepped
reinforcing tubes to allow it to act as a roll-over pro-
tection. During the rollover all of the forces exerted
on the A-pillar of the windshield frame are transmit-
ted as a Moment (Torque) to the bottom of the A-
pillar where stepped reinforced tubes are reinforced.
ART-E46BODY4
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E46 Models
Rear Bulkheads
The rear bulkheads are redesigned to support the roll-
over protection and seat belts. They are welded to
increase structural rigidity and to secure rear seat, rear
seat belts and the mounting point for the ISO child seat.
ART-E46BODY5
Tension Strut
Tension struts are integrated into the rear of the
body shell to improve the torsional rigidity by not
allowing body twist in the rear. It also keeps the
rear end of the car intact with the middle floor
pan.
41E46STRUT0100
41
E46 Models
REAR SEATS
The E46iC is designed as a four passenger vehicle. Only two seat belts are installed in the
rear that correspond to the seat belt system of the E36iC.
The E46iC is equipped with child seat mounting brackets on the left and right sides below
the seat base. The brackets conform to ISO (International Organization of Standardization)
for placement on the rear floor pan. Any ISO child seat can be installed by simply sliding
the seat into position between the seat base and backrest and locking it into place.
42
E46 Models
VARIABLE CONVERTIBLE TOP STORAGE COMPARTMENT FLOOR
The trunk of the E46 convertible offers a new feature called the “Variable Convertible Top
Storage Compartment Floor”. This feature allows the luggage storage area to be enlarged
by approximately 40 liters when the soft top is raised or removed for hard top installation.
The variable compartment floor is constructed of plastic with fabric covering. It is hinged
mechanically so that it can be rotated up into the top storage area providing additional lug-
gage storage space in the trunk. The floor is hinged at four points to allow it to articulate
and fold upwards:
43
E46 Models
Actuating Lever
Dampening Piston
System Operation:
• The convertible top must be raised or removed from the storage compartment.
• Pull the actuating lever rear wards and push it down and toward the rear bulkhead.
44
E46 Models
E46 ALL-WHEEL DRIVE SYSTEM
Objectives
45
E46 Models
Introduction
The E46/16 introduces the return of the BMW all-wheel drive car to the United States. This
time all-wheel drive will be an option (SA 203), available on E46 sedans and Sport Wagons
beginning 2001M.Y.
Vehicles with the all-wheel drive option have been given the engineering designation of
E46/16.
One of the significant changes from the previous E30 ix is that the E46/16 does not use a
viscous coupling or limited slip differential. The all-wheel drive system has largely been
taken from the X5 concept. It uses two open differentials and a single speed transfer case.
Power distribution is 38% to the front and 62% to the rear, giving the E46/16 the feel of a
genuine rear-drive road car.
With it’s additional 17mm ground clearance, the xi is particularly suited to stretches of snow
and ice covered roads and its sure footedness is made possible by the use of the Bosch
DSC III 5.7 system, first used on the X5.
Performance of the all-wheel drive E46 does not suffer either, this is because of a light-
weight all-wheel drive system that only adds 100kg (220lbs). Weight distribution is largely
unaffected at 52.7% front and 47.3% rear (2wd: 51.0% front, 49.0% rear).
325xi
46
E46 Models
Changes from the standard drive version are:
• A specially designed body pan with a widened transmission tunnel and modifications on
the driver’s side to accept the transfer case.
• Modified oil pan and engine mounts to provide access for the front axles.
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E46 Models
Chassis
Front Axle
The front axle has been completely re-designed over the standard drive E46. All
components are constructed of steel.
The front sway bar has been increased in diameter to 23.5mm (2wd standard: 23mm,
sports suspension: 24mm) to accommodate the additional weight. A sports suspension
option is not available for the xi.
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E46 Models
The struts are shorter than the 2wd and there are reinforcement plates between the strut
bearing and the sheet metal of the strut towers to prevent deformation when traveling on
very poor road surfaces.
Steering
The rack and pinion steering unit
has been modified from the 2wd.
It is constructed with a
larger diameter piston.
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E46 Models
Differential and Front Axles
The differential for the front axle is bolted to left side of the engine oil pan. The differential
is driven by a 40mm single piece drive
shaft. The drive shaft has universal Right Side Support Housing
joints at both ends.
The oil sump has been modified to accommodate the right side axle. A connecting tube is
welded into the oil pan. A shaft runs inside of the connecting tube between the front
differential and the axle shaft on the right side.
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E46 Models
Rear Axle
The complete rear axle and the rear differential are the same as the 2wd version of the 325i
and 330i.
The rear spring/strut travel of the E46/16 is approximately 17mm less than the 2wd version.
The reason for the reduced travel in the rear is to oppose any excessive body roll as a result
of the higher body profile.
The rear sway bar has been increased in diameter to 20mm (2wd standard: 18mm, sports
suspension: 19mm) to accommodate the additional weight.
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E46 Models
Transmissions
There are two transmission variants for the 325xi and 330xi.
Transmission Cross-member
Along with the lower transfer case section, the
cast aluminum transmission cross-member is a
low profile design to optomize ground clear-
ance.
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E46 Models
Transfer Case
The Transfer case for the E46/16 is the NV 124 manufactured by New Venture. The
primary difference between the NV 124 and the NV 125 used in the X5 SAV is that it uses
gears instead of a drive chain for torque transfer to the front axle.
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E46 Models
Output to Rear Axle
From the Ring Gear , the power is transmitted via the driveshaft to the rear axle differential.
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E46 Models
Review Questions
4. Describe the changes made to the E46 front and rear suspension from the previous
3 series (E36).
5. Where is the emergency release for the tailgate located on the E46 Sport Wagon?
6. What allows the windshield frame of the E46 Convertible to act as a roll over protection
device?
7. How is the floor pan on the E46 Convertible improved for structural rigidity?
8. Describe the components used in the E46 all-wheel drive running gear.
9. Describe the changes made to the front suspension of the E46 to accommodate the
all-wheel drive system.
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E46 Models