TRANSMISSION Automatic Transmission - VT40 (MRG) - Repair Instructions - On Vehicle - Trailblazer

2021 TRANSMISSION
Automatic Transmission - VT40 (MRG) - Repair Instructions - On Vehicle - Trailblazer
REPAIR INSTRUCTIONS - ON VEHICLE

TRANSMISSION ADAPTIVE PRESSURE RESET
Diagnostic Instructions
Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System
Check - Vehicle
Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
Description
This procedure resets the control module learned values of the component/system: Transmission Adaptive
Pressure Functions. The purpose of the adapt function is to automatically compensate the shift quality for the
various vehicle shift control systems. The adapt function is a continuous process that will help to maintain
optimal shift quality throughout the life of the vehicle.
When to Perform the Procedure
NOTE: Failure to perform this procedure may result in poor system performance,
DTCs being set, or customer dissatisfaction.
Perform this procedure when the following component has been serviced:
K71 Transmission Control Module

Q77 Transmission Control Solenoid Valve
T12 Automatic Transmission Assembly
Any condition/repair related to the following: Shift Quality
Calibration Update/Software Update
Control Valve Assembly
Primary Pulley/Secondary Pulley
Torque Converter
Reference Information
Scan Tool Reference
Control Module References
With Scan Tool
1. Ignition - On / Vehicle - In Service Mode

2. Select: Module Diagnostics
3. Select: K71 Transmission Control Module
4. Select: Configuration/Reset Functions
5. Select: Transmission Adaptive Pressure Reset
NOTE: The scan tool does not display the learn/reset status.
6. Follow the instructions on the scan tool. - The procedure will complete within 10 s
7. Perform the following action: Road Test
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification
TRANSMISSION CONTROL LEVER KNOB REPLACEMENT

Removal Procedure
1. Turn the ignition switch to the On position, engine Off.

2. Apply the parking brake.
3. Place the transmission control in the Neutral position.
4. Turn the ignition switch to the Off position.
5.
Using a trim tool, release the retainers (arrows) from the front floor console.
6. Release the rear locating tab (1) from the front floor console.
7. Pull the transmission control lever boot bezel up to gain access to the electrical connector.
8.
Electrical Connector (1) - Disconnect

9.
Pull the transmission control lever boot bezel (1) up to gain access to the transmission control lever boot
retaining ring (2).
10. Release (arrows) the 2 latches of the transmission control lever boot retaining ring to separate the
transmission control lever boot from the transmission control lever knob.
11. Push the transmission control lever boot bezel along with the retaining ring down to gain access to the
transmission control lever knob fastener.
12.
Using a trim tool, release the 2 retainers (arrows) of the knob cover (1) to remove the transmission
control lever knob fastener (2) and pull the bottom of the knob cover slightly.
13. Transmission Control Lever Knob Fastener (2) - Remove

14.
Transmission Control Lever Knob (1) @ Transmission Control Lever (3) - Remove
15. Transmission Control Lever Boot (2) @ Transmission Control Lever - Remove
Installation Procedure
1.
Transmission Control Lever Boot (2) @ Transmission Control Lever (3) - Install
2. Transmission Control Lever Knob (1) @ Transmission Control Lever - Install
3.
NOTE: Ensure the correct orientation of the transmission control lever knob
fastener.
Transmission Control Lever Knob Fastener (2) - Install

4. Install the transmission control lever knob cover (1).
5. Check the transmission control lever knob for proper seat by pulling and twisting.
6.
Pull the transmission control lever boot bezel (1) along with the transmission control lever boot retaining
ring (2) up.
7. Install the transmission control lever boot retaining ring to the transmission control lever knob. The 2
latches (arrows) of the transmission control lever boot retaining ring must engage noticeable.
8. Push the transmission control lever boot bezel down.
9.
Electrical Connector (1) - Connect

10.
Insert the rear locating tab (1) into the front floor console.
11. Seat the retainers (arrows) of the bezel into the front floor console.
12. Turn the ignition switch to On position, engine Off.
13. Place transmission control in the Park position.
14. Un-apply the parking brake.
15. Turn the ignition switch to the Off position.
AUTOMATIC TRANSMISSION RANGE SELECTOR LEVER CABLE REPLACEMENT

Removal Procedure
1. Set the park brake and chock the wheels.

2. Air Cleaner Assembly - Remove
{With LIH} Air Cleaner Assembly Replacement
{With L3T} Air Cleaner Assembly Replacement
3.
Wiring Harness Retainer (1) @ Battery Tray - Remove

4.
Automatic Transmission Range Selector Lever Cable Bolt (1) - Remove
5. Slide the retainer lock (2) forward to expose the cable adjustment retainer (3).
6. Using a suitable tool, raise the cable adjustment retainer (3) to the unlock position.
7. Automatic Transmission Range Selector Lever Cable (4) @ Range Selector Lever Cable Lever - Remove
8. Front Floor Console - Remove - Front Floor Console Replacement
9.
Transmission Range Selector Lever Cable Grommet Nut (1) - Remove [2x]
10.
Remove the range selector lever cable bolt (1) from the transmission control.
NOTE: The cable bolt (2) is not separated from the range selector lever cable.
11. Remove the range selector lever cable bolt (2) along with the range selector lever cable (3) from the
transmission control.
12. Remove the range selector lever cable from vehicle by pulling it into the interior.
1. Prepare the range selector lever cable bolt (2) for installation as follows:
1. Remove any loose cured adhesive from the external threads of the component using a lint free
cloth.
2. Thread the cleaned component into the internal mating threads and remove to loosen trapped cured
adhesive.
3. Apply thread locking adhesive to the external threads of the component.
4. Ensure there are no gaps in the thread locking adhesive once applied to the component.
2. Install the range selector lever cable to vehicle by installing it from the interior.
3.
Range Selector Lever Cable (3) @ Transmission Control - Install
CAUTION: Fastener Caution
4. Install the 2 range selector lever cable bolts (1, 2) and tighten to 9 N.m (80 lb in).
5.
Transmission Range Selector Lever Cable Grommet Nut (1) - Install and tighten [2x] 9 N.m (80 lb in)
6. Front Floor Console - Install - Front Floor Console Replacement
7.
Automatic Transmission Range Selector Lever Cable (4) @ Range Selector Lever Cable Lever - Install
8. Automatic Transmission Range Selector Lever Cable Bolt (1) - Install and tighten 9 N.m (80 lb in)
9. Depress the cable adjustment retainer (3) locking the retainer completely.
10. Slide the retainer lock (2) rearward to cover the cable adjustment retainer (3).
11. Range Selector Lever Cable - Adjust - Range Selector Lever Cable Adjustment
12.
Wiring Harness Retainer (1) @ Battery Tray - Install
13. Air Cleaner Assembly - Install

AUTOMATIC TRANSMISSION RANGE SELECTOR LEVER CABLE LEVER REPLACEMENT

Callout Component Name
Preliminary Procedures
1. Remove the air cleaner assembly.

2. Remove the automatic transmission range selector lever cable from the range selector lever cable
lever. Automatic Transmission Range Selector Lever Cable Replacement
1 Automatic Transmission Range Selector Lever Nut
WARNING:
Hold the
transmission
range
selector
lever while
removing or
installing the
lever
retaining
nut. Failure
to hold the
lever can
cause
damage to
the
transmission
internal park
system
components
which could
allow the
vehicle to
roll when
placed in the
park
position.
CAUTION:
Fastener
Caution
Tighten
30 N.m (22 lb ft)
Automatic Transmission Range Selector Lever Cable Lever
Procedure
2
After installing the range selector lever cable, perform a range selector lever cable
adjustment. Range Selector Lever Cable Adjustment
TRANSMISSION CONTROL MODULE REPLACEMENT

1. Remove the left front tire and wheel assembly. Tire and Wheel Removal and Installation
2. Front Wheelhouse Liner - Left Side - Remove - Front Wheelhouse Liner Replacement
Transmission Control Module
Procedure
1 1. Disconnect the electrical connector.

2. Remove the transmission control module from the module bracket by releasing the
retaining tabs.
3. Program the transmission control module. Control Module References
TRANSMISSION CONTROL MODULE BRACKET REPLACEMENT

Preliminary Procedure
Transmission Control Module Replacement
Transmission Control Module Bracket Nut [2x]
CAUTION:
Fastener
Caution
Procedure
NOTE:
The body to
1 front wiring
harness
connector
needs to be
removed to
remove and
install the
bracket nut.
Electrical Connector - Disconnect

Tighten
9 N.m (80 lb in)
2 Transmission Control Module Bracket
TRANSMISSION CONTROL REPLACEMENT (WITH BASE)

1. Front Floor Console Replacement
WARNING:
After
installing the
transmission
range
selector shift
cable, pull
up and push
down on
ALL
connections
to verify that
the
connections
are fully
seated and
properly
engaged.
Failure to
perform this
task can
result in the
vehicle not
being able to
shift into
PARK
causing
potential
vehicle
damage and
bodily injury.
2. Automatic Transmission Range Selector Lever Cable @ Automatic Transmission Control -

Disconnect Automatic Transmission Range Selector Lever Cable Replacement
3. Disconnect the electrical connector.
Transmission Control Bolt [4x]
CAUTION:
Fastener
1 Caution
Tighten
9 N.m (80 lb in)
Transmission Control
Procedure
2
TRANSMISSION CONTROL REPLACEMENT (WITHOUT BASE)

Removal Procedure
1. Set the park brake.

2. Front Floor Console - Remove - Front Floor Console Replacement
3. Automatic Transmission Range Selector Lever Cable @ Transmission Control - Disconnect - Automatic
Transmission Range Selector Lever Cable Replacement
4. Disconnect the transmission control electrical connector.
5.
Remove the main shaft bolt nut and washer (1) from the transmission control assembly.
6.
Remove the main shaft bolt (1).
7.
Pull the transmission control assembly (1) rearward and upward to unseat it from the transmission control
base.
8. Remove the transmission control assembly from the vehicle.
1. Position the transmission control assembly to the transmission control base.

2.
Push the transmission control assembly (1) downward and forward to seat it to the transmission control
base.
3.
NOTE: Ensure the flats of the bolt align with the transmission control assembly
flat points inside the base before tightening the nut.
Install the main shaft bolt (1).

4.
CAUTION: Fastener Caution .
NOTE: When installing the transmission control main shaft bolt, the face of the
bolt must be held in the slot of the mounting bracket as the nut is torqued
to ensure it remains seated and doesn't rotate out of the slot. Failure to
perform this task can result in a loose shifter feel, squeaks & rattles, or
excessive cross car lash resulting in a customer's poor perceived quality
of the system.
Install the main shaft bolt nut and washer (1) to the transmission control assembly and tighten to 7 N.m
(62 lb in).
5. Connect the transmission control electrical connector.

6. Automatic Transmission Range Selector Lever Cable @ Transmission Control - Connect - Automatic
Transmission Range Selector Lever Cable Replacement
7. Front Floor Console - Install - Front Floor Console Replacement
8. Release the park brake.
RANGE SELECTOR LEVER CABLE ADJUSTMENT
1. Set the park brake and chock the wheels.

2. Air Cleaner Assembly - Remove
3.
Slide the retainer lock (1) forward to expose the cable adjustment retainer (2).
5. Verify that the range selector lever cable lever is in position "P" by turning the range selector lever cable
lever clockwise.
6.
Verify that the transmission control lever (1) is in position "P".

7.
Depress the cable adjustment retainer (2) locking the retainer completely.
9. Air Cleaner Assembly - Install
10. Check the transmission range select lever in all gear selections for proper operation.
VENT HOSE REPLACEMENT (L3T)

Air Cleaner Outlet Duct Replacement
Transmission Vent Hose
1 Procedure
Unclip the transmission vent hose clip.
VENT HOSE REPLACEMENT (LIH)

Air Cleaner Outlet Front Duct Replacement
1 Transmission Vent Hose
TRANSMISSION FLUID FILTER REPLACEMENT (L3T)
Fig. 1: Identifying Transmission Fluid Filter Components (L3T)

Courtesy of GENERAL MOTORS COMPANY

1. Engine Mount Brace Replacement (RH) , or Engine Mount Brace Replacement (LH, FWD) ,
or Engine Mount Brace Replacement (Rear)
2. Automatic Transmission Range Selector Lever Cable Lever Replacement
Transmission Wiring Harness Bracket Bolt [2x]
CAUTION:
Fastener
1 Caution
Tighten
9 N.m (80 lb in)
Wiring Harness Retainer [2x]
2 Procedure
Unclip transmission wiring harness retainers and position the wiring harness out of way
Automatic Transmission Fluid Filter
Procedure
NOTE:
Install a
NEW filter.
3 DO NOT
reuse old
filter.
Tighten
60 N.m (44 lb ft)
Special Tools
DT-52316 Filter Remove/Install Tool
Equivalent regional tools: Special Tools .
TRANSMISSION FLUID FILTER REPLACEMENT (LIH)

Fig. 2: Identifying Transmission Fluid Filter Components (LIH)

1. Engine Mount Brace Replacement (LH) , or Engine Mount Brace Replacement (Rear)
2. Automatic Transmission Range Selector Lever Cable Lever Replacement
CAUTION:
Fastener
1 Caution
Tighten
9 N.m (80 lb in)
Wiring Harness Retainer [2x]
2 Procedure
Unclip transmission wiring harness retainers and position the wiring harness out of way
Automatic Transmission Fluid Filter
Procedure
NOTE:
Install a
NEW filter.
3 DO NOT
reuse old
filter.
Tighten
60 N.m (44 lb ft)
Special Tools
DT-52316 Filter Remove/Install Tool
TRANSMISSION FLUID FILLER CAP REPLACEMENT (L3T)

Air Cleaner Assembly Replacement
1 Transmission Fluid Filler Cap
TRANSMISSION FLUID FILLER CAP REPLACEMENT (LIH)

Air Cleaner Assembly Replacement
1 Transmission Fluid Filler Cap
MANUAL SHIFT DETENT LEVER SHAFT REPLACEMENT

Removal Procedure
1. Range Selector Lever Cable Lever - Remove - Automatic Transmission Range Selector Lever Cable
Lever Replacement
2. Control Valve Body - Remove - Control Valve Body Replacement
3.
Manual Shift Detent Spring Bolt (1) - Remove and DISCARD
4. Manual Shift Detent Lever Spring (2) @ Manual Shift Detent Lever - Remove
5.
Manual Shift Detent Lever Hub Pin (1) - Remove and DISCARD
6. Manual Shift Detent Lever Shaft (2) - Remove

7. Manual Shift Detent Lever (3) - Remove
8. Park Pawl Actuator (4) - Remove
1.
Manual Shift Detent Lever (3) - Install
2. Park Pawl Actuator (4) - Install
NOTE: Lubricate the shaft with ATF to prevent damage to the manual shift shaft
seal during installation.
3. Manual Shift Detent Lever Shaft (2) - Install

4. Install the NEW manual shaft detent lever hub pin (1) to height of 7.9 mm (0.31 in) (a).
5.
Manual Shift Detent Lever Spring (2) @ Manual Shift Detent Lever - Install

Manual Shift Detent Spring Bolt (1) - Install NEW and tighten 9 N.m (80 lb in)
6. Control Valve Body - Install - Control Valve Body Replacement
7. Range Selector Lever Cable Lever - Install - Automatic Transmission Range Selector Lever Cable
Lever Replacement
MANUAL SHIFT SHAFT SEAL REPLACEMENT
Special Tools
DT-51672 Manual Shaft Seal Installer

DT-52322 Seal Remover
Equivalent regional tools: Special Tools
Removal Procedure
1. Remove the manual shift detent lever shaft assembly. Manual Shift Detent Lever Shaft Replacement
2.
CAUTION: Do not damage the case bore during removal of the manual shift shaft
seal.
Remove and DISCARD the manual shift shaft seal (1) using DT-52322 Seal Remover (2).
1.
CAUTION: When installing the seal, ensure the seal lip is firmly seated against the
case bore surface. Do not allow the seal lip to be crushed, or a leak may
result.
Install a NEW manual shift shaft seal (1) using DT-51672 Manual Shaft Seal Installer (2).
2. Install the manual shift detent lever shaft assembly. Manual Shift Detent Lever Shaft Replacement
FRONT WHEEL DRIVE SHAFT SEAL REPLACEMENT - LEFT SIDE

Front Wheel Drive Half Shaft Replacement - Left Side
Front Wheel Drive Shaft Oil Seal
Procedure
1. For seal removal use GE-6125-1B slide hammer with DT-23129 universal seal
remover.
2. For seal installation use J-22828 tube driver with DT-50896 front wheel drive shaft
oil seal installer.
1 Special Tools
DT-23129 Universal seal Remover

DT-50896 Front Wheel Drive Shaft Oil Seal Installer
GE-6125-1B Slide Hammer
J-22828 Tube Driver
FRONT WHEEL DRIVE SHAFT SEAL REPLACEMENT - RIGHT SIDE

Front Wheel Drive Half Shaft Replacement - Right Side (AWD) , or Front Wheel Drive Half Shaft
Replacement - Right Side (FWD)
Front Wheel Drive Shaft Oil Seal
Procedure
1. For seal removal use GE-6125-1B slide hammer with DT-23129 universal seal
remover.
2. For seal installation use J-22828 tube driver with DT-50896 front wheel drive shaft
oil seal installer.
1 Special Tools
DT-23129 Universal seal Remover

DT-50896 Front Wheel Drive Shaft Oil Seal Installer
GE-6125-1B Slide Hammer
J-22828 Tube Driver
CONTROL VALVE BODY COVER REPLACEMENT (L3T)

Removal Procedure
1. Disconnect the battery negative cable. Battery Negative Cable Disconnection and Connection
2. Drain the transmission fluid. Transmission Fluid Drain and Fill (L3T)
3.
Air Cleaner Assembly (1) - Remove - Air Cleaner Assembly Replacement
4.
Charge Air Cooler Inlet Air Hose (1) - Remove - Charge Air Cooler Inlet Air Hose Replacement
5.
Transmission Fluid Cooler Inlet and Outlet Pipe - Remove - Transmission Fluid Cooler Inlet and
Outlet Pipe Replacement
6.
Disconnect the control valve body transmission control module electrical connector (1), then unclip the 5
wiring harness retainers (2).
7. position the battery positive cable out of the way.

8. Automatic Transmission Fluid Cooling Heat Exchanger Inlet and Outlet Hose - Remove - Automatic
Transmission Fluid Cooling Heat Exchanger Inlet and Outlet Hose Replacement (MRG)
9.
Transmission Wiring Harness Bracket Nut (1) - Remove [3x]
10. Transmission Wiring Harness Bracket (2, 3, 4) - Remove [3x]

11.
Fig. 3: Identifying Control Valve Body Cover Bolts/Studs With Loosening Sequence
Control Valve Body Cover Stud (1) - Remove [8x]

12. Control Valve Body Cover Bolt (2) - Remove [4x]
13.
Control Valve Body Cover (1) - Remove
NOTE: The control valve body cover seal is reusable. Inspect the seal to
determine if it may be reused.
14. Control Valve Body Cover Seal (2) - Remove

15. Control Valve Body Cover Wiring Connector Hole Seal (3) - Remove and DISCARD
1.
Control Valve Body Cover Wiring Connector Hole Seal (3) - Install NEW
2. Control Valve Body Cover Seal (2) - Install

3. Control Valve Body Cover (1) - Install
4.
Fig. 4: Identifying Control Valve Body Cover Bolts/Studs With Tightening Sequence
Control Valve Body Cover Stud (1) - Install [8x] - Hand tighten
5. Control Valve Body Cover Bolt (2) - Install [4x] - Hand tighten
6. Control Valve Body Cover Stud (1) and Control Valve Body Cover Bolt (2) - Tighten in sequence [12x] 9
N.m (80 lb in)
7.
Transmission Wiring Harness Bracket (2, 3, 4) - Install [3x]
8. Transmission Wiring Harness Bracket Nut (1) - Install and tighten [3x] 9 N.m (80 lb in)
9. Automatic Transmission Fluid Cooling Heat Exchanger Inlet and Outlet Hose - Install - Automatic
Transmission Fluid Cooling Heat Exchanger Inlet and Outlet Hose Replacement (MRG)
10. Install the battery positive cable to the front of the transmission.
11.
Connect the control valve body transmission control module electrical connector (1), then clip the 5
12.
Transmission Fluid Cooler Inlet and Outlet Pipe - Install - Transmission Fluid Cooler Inlet and Outlet
Pipe Replacement
13.
Charge Air Cooler Inlet Air Hose (1) - Install - Charge Air Cooler Inlet Air Hose Replacement
14.
Air Cleaner Assembly (1) - Install - Air Cleaner Assembly Replacement
15. Connect the battery negative cable. Battery Negative Cable Disconnection and Connection
16. Fill the transmission with transmission fluid. Transmission Fluid Drain and Fill (L3T)
17. Check for leaks.
CONTROL VALVE BODY COVER REPLACEMENT (LIH)

Removal Procedure
1. Disconnect the battery negative cable. Battery Negative Cable Disconnection and Connection
2. Drain the transmission fluid. Transmission Fluid Drain and Fill (LIH)
3.
4.
5. Transmission Fluid Cooler Inlet Pipe @ Transmission - Remove - Transmission Fluid Cooler Inlet Pipe
Replacement (LIH)
6. Transmission Fluid Cooler Outlet Pipe @ Transmission - Remove - Transmission Fluid Cooler Outlet
Pipe Replacement (LIH)
7.
8. Position the battery positive cable out of the way.
9.

11.
Fig. 5: Identifying Control Valve Body Cover Bolts/Studs With Loosening Sequence
Control Valve Body Cover Stud (1) - Remove [8x]

12. Control Valve Body Cover Bolt (2) - Remove [4x]
13.
Control Valve Body Cover (1) - Remove
NOTE: The control valve body cover seal is reusable. Inspect the seal to
determine if it may be reused.
14. Control Valve Body Cover Seal (2) - Remove

15. Control Valve Body Cover Wiring Connector Hole Seal (3) - Remove and DISCARD
1.
Control Valve Body Cover Wiring Connector Hole Seal (3) - Install NEW
2. Control Valve Body Cover Seal (2) - Install

3. Control Valve Body Cover (1) - Install
4.
Fig. 6: Identifying Control Valve Body Cover Bolts/Studs With Tightening Sequence
Control Valve Body Cover Stud (1) - Install [8x] - Hand tighten
5. Control Valve Body Cover Bolt (2) - Install [4x] - Hand tighten
6. Control Valve Body Cover Stud (1) and Control Valve Body Cover Bolt (2) - Tighten in sequence [12x] 9
N.m (80 lb in)
7.
10.
11. Transmission Fluid Cooler Outlet Pipe @ Transmission - Install - Transmission Fluid Cooler Outlet
12. Transmission Fluid Cooler Inlet Pipe @ Transmission - Install - Transmission Fluid Cooler Inlet Pipe
Replacement (LIH)
13.
14.
15. Connect the battery negative cable. Battery Negative Cable Disconnection and Connection
16. Fill the transmission with transmission fluid. Transmission Fluid Drain and Fill (LIH)
17. Check for leaks.
CONTROL VALVE BODY REPLACEMENT

Removal Procedure
1. Control Valve Body Cover - Remove - Control Valve Body Cover Replacement (L3T), or Control
Valve Body Cover Replacement (LIH)
2.
Remove the control valve body (1) from the transmission. Control Valve Body Assembly Removal
1.
Install the control valve body (1) to the transmission. Control Valve Body Assembly Installation
2. Control Valve Body Cover - Install - Control Valve Body Cover Replacement (L3T), or Control Valve
Body Cover Replacement (LIH)
3. Perform the solenoid valve characterization programming procedure. Q77 Transmission Control
Solenoid Valve Characterization Programming (VT40)
CONTROL VALVE SOLENOID BODY REPLACEMENT

Removal Procedure
2.
Fig. 7: Exploded View Of Control Valve Solenoid Body Components And Bolt Identification
Remove the control valve solenoid body (7) from the transmission. Control Valve Body Assembly
Removal
1.
Fig. 8: Exploded View Of Control Valve Solenoid Body Components And Bolt Identification
Install the control valve solenoid body (1) to the transmission. Control Valve Body Assembly
Installation
AUTOMATIC TRANSMISSION INPUT SPEED SENSOR REPLACEMENT

Control Valve Body Replacement
1 Automatic Transmission Input Speed Sensor Bolt
CAUTION:
This vehicle
is equipped
with torque-
to-yield or
single use
fasteners.
Install a
NEW torque-
to-yield or
single use
fastener
when
installing
this
component.
Failure to
replace the
torque-to-
yield or
single use
fastener
could cause
damage to
the vehicle
or
component.
CAUTION:
Fastener
Caution
NOTE:
Install a
NEW bolt.
Do NOT
reuse the old
bolt.
Tighten
1. First Pass: 4 N.m (35 lb in)

2. Final Pass: 45 degrees
Special Tools
DT-48285 Torque Socket
Automatic Transmission Input Speed Sensor
2 Procedure
Perform the transmission adaptive pressure reset. Transmission Adaptive Pressure Reset
AUTOMATIC TRANSMISSION INTERMEDIATE SPEED SENSOR REPLACEMENT

1. Raise and support the vehicle. Lifting and Jacking the Vehicle
2. Front Wheelhouse Liner - Left Side - Remove - Front Wheelhouse Liner Replacement
1 Automatic Transmission Intermediate Speed Sensor Bolt
CAUTION:
This vehicle
is equipped
with torque-
to-yield or
single use
fasteners.
Install a
NEW torque-
to-yield or
single use
fastener
when
installing
this
component.
Failure to
replace the
torque-to-
yield or
single use
fastener
could cause
damage to
the vehicle
or
component.
CAUTION:
Fastener
Caution
NOTE:
Install a
NEW bolt.
Do NOT
reuse the old
bolt.
Tighten
1. First Pass: 4 N.m (35 lb in)

2. Final Pass: 45 degrees
Special Tools
DT-48285 Torque Socket
Automatic Transmission Intermediate Speed Sensor
Procedure
2 1. Unclip the wiring harness retainer and disconnect the electrical connector.
2. Perform the transmission adaptive pressure reset. Transmission Adaptive Pressure
Reset
AUTOMATIC TRANSMISSION FLUID LEVEL CONTROL VALVE REPLACEMENT

Control Valve Body Cover Replacement (L3T), or Control Valve Body Cover Replacement (LIH)
1 Automatic Transmission Fluid Level Control Valve
Automatic Transmission Fluid Level Control Valve Seal
NOTE:
2 Install a
NEW seal.
Do NOT
reuse the old
seal.
AUTOMATIC TRANSMISSION FLUID PRESSURE SENSOR REPLACEMENT

Automatic Transmission Wiring Harness Replacement
1 Control Valve Body Bolt [2x] M5 x 98.3
CAUTION:
Fastener
Caution
Tighten
8 N.m (71 lb in)
Control Valve Body Bolt [2x] M5 X 85
2 Tighten
8 N.m (71 lb in)
Automatic Transmission Fluid Pressure Sensor [2x]
3 Procedure
Perform the transmission adaptive pressure reset. Transmission Adaptive Pressure Reset
Automatic Transmission Fluid Pressure Sensor Seal [2x]
NOTE:
4 Install a
NEW seal.
Do NOT
reuse the old
seal.
AUTOMATIC TRANSMISSION CASE COVER PLUG REPLACEMENT
Fig. 9: Identifying Automatic Transmission Case Cover Plug Components


Front Wheelhouse Liner - Left Side - Remove - Front Wheelhouse Liner Replacement
1 Automatic Transmission Case Cover Plug [3x]
NOTE:
If a
significant
amount of
fluid is lost,
correct the
transmission
fluid level.
Transmission
Fluid Level
and
Condition
Check
CAUTION:
Fastener
Caution
Tighten
16 N.m (12 lb ft)
TRANSMISSION MOUNT REPLACEMENT

Removal Procedure
1. Battery Tray @ Vehicle - Remove - Battery Tray Replacement

2. Install the engine support fixture. Engine Support Fixture
3.
Transmission Mount Transmission Side Bolt (1) - Remove and DISCARD [3x]
4.
Transmission Mount Bolt (1) - Remove [2x]
5. Transmission Mount (2) - Remove
1.
Transmission Mount (2) - Install
2. Transmission Mount Bolt (1) - Install and tighten [2x] 100 N.m (74 lb ft)
3.
CAUTION: This vehicle is equipped with torque-to-yield or single use fasteners.

Install a NEW torque-to-yield or single use fastener when installing this
component. Failure to replace the torque-to-yield or single use fastener
could cause damage to the vehicle or component.
Transmission Mount Transmission Side Bolt (1) - Install NEW and tighten [3x]
1. First Pass: 100 N.m (74 lb ft)

2. Final Pass: 60 - 75 degrees
4. Remove the engine support fixture. Engine Support Fixture
5. Battery Tray @ Vehicle - Install - Battery Tray Replacement
TRANSMISSION MOUNT STRUT REPLACEMENT

Removal Procedure
1.
Front Compartment Insulator (1) - Remove - Front Compartment Insulator Replacement (Base)
2.
Transmission Mount Strut Bracket (1) - Remove - Transmission Mount Strut Bracket Replacement
(L3T), or Transmission Mount Strut Bracket Replacement (LIH)
3.
Transmission Mount Strut Bolt-Body Side (1) @ Drivetrain and Front Suspension Cradle - Remove and
DISCARD
4. Transmission Mount Strut (2) @ Drivetrain and Front Suspension Cradle - Remove
1.
Transmission Mount Strut (2) @ Drivetrain and Front Suspension Cradle - Install

2. Transmission Mount Strut Bolt-Body Side (1) @ Drivetrain and Front Suspension Cradle - Install NEW
and tighten
3.
Transmission Mount Strut Bracket (1) - Install - Transmission Mount Strut Bracket Replacement
(L3T), or Transmission Mount Strut Bracket Replacement (LIH)
4.
Front Compartment Insulator (1) - Install - Front Compartment Insulator Replacement (Base)
TRANSMISSION MOUNT STRUT BRACKET REPLACEMENT (L3T)

Removal Procedure
1.
2.
Engine Mount Brace (1) - Remove - Engine Mount Brace Replacement (Rear)
3.
Transmission Mount Strut Bolt-Powertrain Side (1) - Remove
4.
Transmission Mount Strut Bracket Bolt (1) @ Transmission - Remove and DISCARD [3x]
5. Transmission Mount Strut Bracket (2) @ Vehicle - Remove

1.
Transmission Mount Strut Bracket (2) @ Vehicle - Install

2. Transmission Mount Strut Bracket Bolt (1) @ Transmission - Install NEW and tighten [3x]
3.
Transmission Mount Strut Bolt-Powertrain Side (1) - Install and tighten

4.
Engine Mount Brace (1) - Install - Engine Mount Brace Replacement (Rear)
5.
TRANSMISSION MOUNT STRUT BRACKET REPLACEMENT (LIH)

Removal Procedure
1.
2.
Engine Mount Brace (1) - Remove - Engine Mount Brace Replacement (LH, FWD) , or Engine
Mount Brace Replacement (Rear)
3.
Transmission Mount Strut Bolt-Powertrain Side (1) - Remove
4.
Transmission Mount Strut Bracket Bolt (1) @ Transmission - Remove and DISCARD [3x]
5. Transmission Mount Strut Bracket (2) @ Vehicle - Remove
1.
Transmission Mount Strut Bracket (2) @ Vehicle - Install

2. Transmission Mount Strut Bracket Bolt (1) @ Transmission - Install NEW and tighten [3x]
3.
Transmission Mount Strut Bolt-Powertrain Side (1) - Install and tighten

4.
Engine Mount Brace (1) - Install - Engine Mount Brace Replacement (LH, FWD) , or Engine Mount
Brace Replacement (Rear)
5.
TRANSMISSION CONVERTER COVER REPLACEMENT (L3T)

2. Front Wheel Drive Shaft Heat Shield Replacement (L3T)
Transmission Bolt [2x]
CAUTION:
Fastener
1 Caution
Tighten
58 N.m (43 lb ft)
2 Transmission Converter Cover
TRANSMISSION CONVERTER COVER REPLACEMENT (LIH)

1. Remove the right front tire and wheel assembly. Tire and Wheel Removal and Installation
2. Front Wheel Drive Shaft Heat Shield Replacement (LIH)
Transmission Bolt [2x]
CAUTION:
Fastener
1 Caution
Tighten
58 N.m (43 lb ft)
2 Transmission Converter Cover
TORQUE CONVERTER REPLACEMENT

1. Transmission Replacement (LIH), or Transmission Replacement (L3T)

2. Position the transmission so that the front of the torque converter is facing up.
1 Torque Converter
CAUTION:
Lower the
torque
converter
straight
down.
Failure to
lower the
torque
converter
straight
down could
damage the
torque
converter
clutch lip
seal inside
the torque
converter
clutch
assembly.
TORQUE CONVERTER FLUID SEAL REPLACEMENT

Torque Converter Replacement
Torque Converter Fluid Seal
NOTE:
Install a
NEW seal.
Do NOT
reuse the old
seal.
1
Special Tools
DT-6125-1B Slide Hammer

J-29162 Seal Installer
DT-23129 Universal Seal Remover
TORQUE CONVERTER HOUSING FLUID PASSAGE PLUG REPLACEMENT

Fig. 10: Identifying Torque Converter Housing Fluid Passage Plug Components

Raise and support the vehicle. Lifting and Jacking the Vehicle
Torque Converter Housing Fluid Passage Plug [2x]
CAUTION:
Fastener
1 Caution
Tighten
10.5 N.m (93 lb in)
AUTOMATIC TRANSMISSION WIRING HARNESS BRACKET REPLACEMENT (L3T)

1. Battery Tray Replacement

CAUTION:
Fastener
1 Caution
Tighten
9 N.m (80 lb in)
Wire Tie Strap
Procedure
2
Remove and DISCARD the 2 wire tie straps from the bracket. Replace with NEW wire tie
straps.
3 Transmission Wiring Harness Bracket
AUTOMATIC TRANSMISSION WIRING HARNESS BRACKET REPLACEMENT (LIH)

1. Battery Tray Replacement

2. Engine Mount Brace Replacement (LH) , or Engine Mount Brace Replacement (Rear)
CAUTION:
Fastener
1 Caution
Tighten
9 N.m (80 lb in)
Wire Tie Strap
Procedure
2
Remove and DISCARD the 2 wire tie straps from the bracket. Replace with NEW wire tie
straps.
3 Transmission Wiring Harness Bracket
AUTOMATIC TRANSMISSION WIRING HARNESS REPLACEMENT

Removal Procedure
2.
Remove the automatic transmission wiring harness (1) from the transmission. Control Valve Body
Assembly Removal
1.
Install the automatic transmission wiring harness (1) to the transmission. Control Valve Body Assembly
Installation
AUTOMATIC TRANSMISSION CONTROL INDICATOR REPLACEMENT

Front Floor Console Cup Holder Trim Plate Replacement
1 Automatic Transmission Control Indicator Housing Bolt
CAUTION:
Fastener
Caution
Tighten
1.2 N.m (11 lb in)
2 Automatic Transmission Control Indicator
TRANSMISSION FLUID DRAIN AND FILL (L3T)

Removal Procedure
2. Front Compartment Insulator - Remove - Front Compartment Insulator Replacement (Base)
3.
Fig. 11: Identifying Transmission Fluid Drain Plug
Transmission Fluid Drain Plug (1) - Remove
4. Drain transmission fluid into a suitable container.
CAUTION: Component Fastener Tightening Caution
5. Transmission Fluid Drain Plug (1) - Install and tighten 10.5 N.m (93 lb in)
1. Lower the vehicle.

2. Air Cleaner Assembly - Remove - Air Cleaner Assembly Replacement
3.
Transmission Fluid Filler Cap (1) - Remove
4. Fill the transmission to the proper level with the correct fluid. Transmission Fluid Level and Condition
Check , and Adhesives, Fluids, Lubricants, and Sealers
5. Transmission Fluid Filler Cap (1) - Install
6. Air Cleaner Assembly - Install - Air Cleaner Assembly Replacement
7. Front Compartment Insulator - Install - Front Compartment Insulator Replacement (Base)
TRANSMISSION FLUID DRAIN AND FILL (LIH)

Removal Procedure
2. Front Compartment Insulator - Remove - Front Compartment Insulator Replacement (Base)
3.
Fig. 12: Identifying Transmission Fluid Drain Plug
Transmission Fluid Drain Plug (1) - Remove
4. Drain transmission fluid into a suitable container.
CAUTION: Component Fastener Tightening Caution
5. Transmission Fluid Drain Plug (1) - Install and tighten 10.5 N.m (93 lb in)

2. Air Cleaner Assembly - Remove - Air Cleaner Assembly Replacement
3.
Transmission Fluid Filler Cap (1) - Remove
4. Fill the transmission to the proper level with the correct fluid. Transmission Fluid Level and Condition
Check , and Adhesives, Fluids, Lubricants, and Sealers
5. Transmission Fluid Filler Cap (1) - Install
6. Air Cleaner Assembly - Install - Air Cleaner Assembly Replacement
7. Front Compartment Insulator - Install - Front Compartment Insulator Replacement (Base)
TRANSMISSION REPLACEMENT (LIH)

Removal Procedure
1.

2.
Air Cleaner Outlet Rear Duct (2) - Remove - Air Cleaner Outlet Rear Duct Replacement
3. Transmission Fluid - Drain - Transmission Fluid Drain and Fill (LIH)
4.
Battery Tray (3) - Remove - Battery Tray Replacement
5. Engine Mount Brace - Remove - Engine Mount Brace Replacement (LH) , or Engine Mount Brace
Replacement (Rear)
6.
Automatic Transmission Range Selector Lever Cable Bolt (1) - Remove
7. Slide the retainer lock (2) forward to expose the cable adjustment retainer (3).
9. Automatic Transmission Range Selector Lever Cable (4) @ Range Selector Lever Cable Lever - Remove
10.
Wiring Harness Retainer (1) - Unclip
11. Electrical Connector (2) - Disconnect

12.
13. Transmission Fluid Cooler Inlet Pipe @ Transmission - Remove - Transmission Fluid Cooler Inlet Pipe
Replacement (LIH)
14. Transmission Fluid Cooler Outlet Pipe @ Transmission - Remove - Transmission Fluid Cooler Outlet
15. Plug and/or cap the pipes and the transmission to prevent contamination.
16.
17. Position the battery positive cable out of the way.

18.
20.
Wiring Harness Retainer (1) - Unclip [2x]
21.
Retainer (1) - Unclip [3x]
22. Engine Wiring Harness Bracket Bolt (2) - Remove

23. Engine Wiring Harness Bracket (3) - Remove
24.
Transmission Bolt (1) - Remove [2x]
25. Transmission Wiring Harness Bracket (2) - Remove

26. Exhaust Front Muffler - Remove - Exhaust Front Muffler Replacement (FWD)
27.
Drivetrain and Front Suspension Cradle (1) - Remove - Drivetrain and Front Suspension Cradle
Removal and Installation (FWD)
28. Transmission Mount Strut Bracket - Remove - Transmission Mount Strut Bracket Replacement
(LIH)
29.
Front Wheel Drive Half Shaft - Left Side (1) - Remove - Front Wheel Drive Half Shaft Replacement -
Left Side
30.
Front Wheel Drive Half Shaft - Right Side (1) - Remove - Front Wheel Drive Half Shaft Replacement
- Right Side (FWD)
31. Front Wheel Drive Shaft Heat Shield - Remove - Front Wheel Drive Shaft Heat Shield Replacement
(LIH)
32.
Starter (3) - Remove - Starter Replacement (LIH)
33. Mark the relationship of the flywheel to the torque converter for reassembly.
34.
Remove and DISCARD the torque converter bolts (1).

36. Engine Support Fixture - Install - Engine Support Fixture
37.
Transmission Mount (2) - Remove - Transmission Mount Replacement
38. Raise the vehicle.

39. Use a transmission jack in order to support the transmission.
40.
Transmission Bolt (1) - Remove

41.
42.
43. Transmission Converter Cover (2) - Remove
NOTE: Ensure the torque converter remains securely in place on the

transmission input shaft while separating and removing the transmission.
44. Separate the transmission from the engine.

45. Lower the transmission with the transmission jack far enough to remove the transmission.
46. Transfer components as necessary.
1. Raise the transmission with the transmission jack and position the transmission to the engine.
2.
Transmission Converter Cover (2) - Install
3. Transmission Bolt (1) - Install and tighten [3x] 58 N.m (43 lb ft)
4.
Transmission Bolt (1) - Install and tighten 58 N.m (43 lb ft)
5.

6. Remove the transmission jack.
7. Align the mark of the flywheel to the mark on the torque converter for reassembly.
8.
Install the NEW torque converter bolts (1) and tighten to 60 N.m (44 lb ft).
9.
Starter (3) - Install - Starter Replacement (LIH)

11.
Transmission Mount (2) - Install - Transmission Mount Replacement
12. Front Wheel Drive Shaft Heat Shield - Install - Front Wheel Drive Shaft Heat Shield Replacement
(LIH)
13.
Front Wheel Drive Half Shaft - Right Side (1) - Install - Front Wheel Drive Half Shaft Replacement -
Right Side (FWD)
14.
Front Wheel Drive Half Shaft - Left Side (1) - Install - Front Wheel Drive Half Shaft Replacement -
Left Side
15. Transmission Mount Strut Bracket - Install - Transmission Mount Strut Bracket Replacement (LIH)
16.
Drivetrain and Front Suspension Cradle (1) - Install - Drivetrain and Front Suspension Cradle
Removal and Installation (FWD)
17. Exhaust Front Muffler - Install - Exhaust Front Muffler Replacement (FWD)
18. Engine Support Fixture - Remove - Engine Support Fixture
19.
Transmission Wiring Harness Bracket (2) - Install
21.
Engine Wiring Harness Bracket (3) - Install
22. Engine Wiring Harness Bracket Bolt (2) - Install and tighten 9 N.m (80 lb in)
23. Retainer (1) - Clip [3x]
24.
Wiring Harness Retainer (1) - Clip [2x]

25.
28.
29. Transmission Fluid Cooler Outlet Pipe @ Transmission - Install - Transmission Fluid Cooler Outlet
30. Transmission Fluid Cooler Inlet Pipe @ Transmission - Install - Transmission Fluid Cooler Inlet Pipe
Replacement (LIH)
31.
32.
Electrical Connector (2) - Connect
33. Wiring Harness Retainer (1) - Clip

34.
Automatic Transmission Range Selector Lever Cable (4) @ Range Selector Lever Cable Lever - Install
35. Automatic Transmission Range Selector Lever Cable Bolt (1) - Install and tighten 9 N.m (80 lb in)
36. Depress the cable adjustment retainer (3) locking the retainer completely.
38. Engine Mount Brace - Install - Engine Mount Brace Replacement (LH) , or Engine Mount Brace
Replacement (Rear)
39.
Battery Tray (3) - Install - Battery Tray Replacement
41. Transmission Fluid - Fill - Transmission Fluid Drain and Fill (LIH)
42.
Air Cleaner Outlet Rear Duct (2) - Install - Air Cleaner Outlet Rear Duct Replacement
43.
44. After repairs, refer to Control Module References for programming and set up procedures.
46. Road test the vehicle.
TRANSMISSION REPLACEMENT (L3T)

Removal Procedure
1. Transmission Fluid - Drain - Transmission Fluid Drain and Fill (L3T)

2. After removing the related parts for the powertrain assembly removal, remove the powertrain assembly
from the vehicle. Engine Replacement
3.
Unclip the transmission vent hose retainer (1) and the wiring harness retainer (2).
4. Disconnect the electrical connector (3).
5.
Disconnect the control valve body transmission control module electrical connector (1), then unclip the
wiring harness retainer (2).
6.

8.
Automatic Transmission Fluid Cooling Exchanger Bolt (1) - Remove [3x]
9. Automatic Transmission Fluid Cooling Exchanger (2) - Remove
10.
Heater Outlet Pipe (1) - Remove - Heater Outlet Pipe Replacement
11.
12. Starter - Remove - Starter Replacement (L3T)

13. Mark the relationship of the flywheel to the torque converter for reassembly.
14.
Torque Converter Bolt (1) - Remove and DISCARD [3x]
15.
16.

17.
18. Transmission Converter Cover (2) - Remove
NOTE: Ensure the torque converter remains securely in place on the

transmission input shaft while separating and removing the transmission.
19. Separate the transmission from the engine.

20. Transfer components as necessary.
1. Install the transmission to the engine.
2.
Transmission Converter Cover (2) - Install
4.
5.
6. Align the mark of the flywheel to the mark on the torque converter for reassembly.
7.
Torque Converter Bolt (1) - Install NEW and tighten [3x] 60 N.m (44 lb ft)
8. Starter - Install - Starter Replacement (L3T)

9.
Transmission Bolt (1) - Install and tighten [2x] 58 N.m (43 lb ft)
10.
Heater Outlet Pipe (1) - Install - Heater Outlet Pipe Replacement
11.
Automatic Transmission Fluid Cooling Exchanger (2) - Install
12. Automatic Transmission Fluid Cooling Exchanger Bolt (1) - Install and tighten [3x] 9 N.m (80 lb in)
13.
15.
Connect the control valve body transmission control module electrical connector (1), then clip the wiring
harness retainer (2).
16.
Connect the electrical connector (3).
17. Clip the transmission vent hose retainer (1) and the wiring harness retainer (2).
18. Install the powertrain assembly to the vehicle and then install the related parts. Engine Replacement
20. Transmission Fluid - Fill - Transmission Fluid Drain and Fill (L3T)
21. After repairs, refer to Control Module References for programming and set up procedures.
23. Road test the vehicle.

TRANSMISSION Automatic Transmission - VT40 (MRG) - Repair Instructions - On Vehicle - Trailblazer

Uploaded by

Copyright:

Available Formats

TRANSMISSION Automatic Transmission - VT40 (MRG) - Repair Instructions - On Vehicle - Trailblazer

Uploaded by

Document Information

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

TRANSMISSION Automatic Transmission - VT40 (MRG) - Repair Instructions - On Vehicle - Trailblazer

Uploaded by

Copyright:

Available Formats

2021 TRANSMISSION

Automatic Transmission - VT40 (MRG) - Repair Instructions - On Vehicle - Trailblazer

REPAIR INSTRUCTIONS - ON VEHICLE

When to Perform the Procedure

K71 Transmission Control Module

Scan Tool Reference

Control Module References

With Scan Tool

1. Ignition - On / Vehicle - In Service Mode

TRANSMISSION CONTROL LEVER KNOB REPLACEMENT

1. Turn the ignition switch to the On position, engine Off.

Electrical Connector (1) - Disconnect

13. Transmission Control Lever Knob Fastener (2) - Remove

2. Transmission Control Lever Knob (1) @ Transmission Control Lever - Install

Transmission Control Lever Knob Fastener (2) - Install

Electrical Connector (1) - Connect

AUTOMATIC TRANSMISSION RANGE SELECTOR LEVER CABLE REPLACEMENT

1. Set the park brake and chock the wheels.

Wiring Harness Retainer (1) @ Battery Tray - Remove

Automatic Transmission Range Selector Lever Cable Bolt (1) - Remove

Range Selector Lever Cable (3) @ Transmission Control - Install

CAUTION: Fastener Caution

Wiring Harness Retainer (1) @ Battery Tray - Install

13. Air Cleaner Assembly - Install

AUTOMATIC TRANSMISSION RANGE SELECTOR LEVER CABLE LEVER REPLACEMENT

1. Remove the air cleaner assembly.

1 Automatic Transmission Range Selector Lever Nut

TRANSMISSION CONTROL MODULE REPLACEMENT

Callout Component Name

Transmission Control Module

1 1. Disconnect the electrical connector.

TRANSMISSION CONTROL MODULE BRACKET REPLACEMENT

Electrical Connector - Disconnect

TRANSMISSION CONTROL REPLACEMENT (WITH BASE)

1. Front Floor Console Replacement

2. Automatic Transmission Range Selector Lever Cable @ Automatic Transmission Control -

TRANSMISSION CONTROL REPLACEMENT (WITHOUT BASE)

1. Set the park brake.

Remove the main shaft bolt (1).

8. Remove the transmission control assembly from the vehicle.

1. Position the transmission control assembly to the transmission control base.

Install the main shaft bolt (1).

CAUTION: Fastener Caution .

5. Connect the transmission control electrical connector.

RANGE SELECTOR LEVER CABLE ADJUSTMENT

1. Set the park brake and chock the wheels.

Verify that the transmission control lever (1) is in position "P".

VENT HOSE REPLACEMENT (L3T)

Callout Component Name

VENT HOSE REPLACEMENT (LIH)

TRANSMISSION FLUID FILTER REPLACEMENT (L3T)

Fig. 1: Identifying Transmission Fluid Filter Components (L3T)

Callout Component Name

TRANSMISSION FLUID FILTER REPLACEMENT (LIH)

Callout Component Name

Transmission Wiring Harness Bracket Bolt [2x]

TRANSMISSION FLUID FILLER CAP REPLACEMENT (L3T)

TRANSMISSION FLUID FILLER CAP REPLACEMENT (LIH)

Callout Component Name

MANUAL SHIFT DETENT LEVER SHAFT REPLACEMENT