Tools Required
J 21366 
 Converter Holding Strap
Removal Procedure
- Raise the vehicle. Refer to 
Lifting and Jacking the Vehicle
 .
 
- Remove the rear propeller shaft. Refer to 
One-Piece Propeller Shaft Replacement
 or 
Two-Piece Propeller Shaft Replacement
 .
 
- Support the transmission with a suitable jack.
 
- Remove the transmission support. Refer to 
Transmission Support Replacement
 .
 
- Remove the exhaust manifold pipe. Refer to 
Exhaust Manifold Pipe Replacement
 .
 
- Remove the transmission mount. Refer to 
Transmission Mount Replacement
 .
 
- Remove the transfer case, if equipped. Refer to 
Transfer Case Assembly Replacement
 for the NVG 149-NP (One Speed Automatic) Transfer Case or 
Transfer Case Assembly Replacement
 for
the NVG 236/246-NP8 (Two Speed Automatic) Transfer Case.
 
- Remove the range selector cable from the transmission range selector lever ball stud and bracket. Refer to 
Range Selector Lever Cable Replacement
 .
 
- Disconnect the electrical harness from the park/neutral position switch, the input speed sensor, and the output speed sensor.
 
- Disconnect the wire harness from the wire loom on the left side of the transmission.
 
- Cut the tie strap to separate the vent hose from the wiring harness.
 
- Remove the flywheel inspection cover.
 
- Mark the torque converter to flywheel orientation.
 
- Remove the torque converter bolts.
 
- Remove the transmission heat shield.
 
- Disconnect the transmission oil cooler lines from the transmission. Refer to 
Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection
 .
 
- Plug the transmission oil cooler line connectors in the transmission case.
 
- Remove the stud and the bolt on the right side securing the transmission to the engine.
 
- Remove the remaining 6 studs and the one bolt securing the transmission to the engine.
 
- Install the 
J 21366 
 onto the transmission bell housing to retain the torque converter.
 
- Pull the transmission straight back.
 
- Remove the transmission from the vehicle.
 
- Flush the transmission oil cooler and lines at this time. Refer to 
Transmission Fluid Cooler Flushing and Flow Test
 .
 
Installation Procedure
- Install the 
J 21366 
 onto the transmission bell housing to retain the torque converter.
 
- Raise the transmission into place and remove the 
J 21366 
 from the transmission.
 
- Slide the transmission straight onto the locating pins while lining up the marks on the flywheel and the torque converter. The torque converter must rotate freely by hand.
 
Notice: Refer to Fastener Notice in the Preface section.
- Install studs and bolt securing the transmission to the engine.
 
Tighten
Tighten the studs and the bolt to 50 N·m (37 lb ft).
- Install the stud and bolt on the right side securing the transmission to the engine.
 
Tighten
Tighten the stud and the bolt to 50 N·m (37 lb ft).
- If reusing the torque converter bolts with a 6.0L engine, clean the bolt threads and apply LOCTITE 242 GM P/N 12345382 (Canadian P/N 10953489),
or equivalent to the threads prior to installation.
 
- If reusing the torque converter bolts with a 8.1L engine, clean the bolt threads and apply LOCTITE 272 GM P/N 12345493 (Canadian P/N 10953488), or equivalent to the threads prior to installation.
 
- Line up the marks made during removal and install the flywheel to torque converter bolts.
 
Tighten
Tighten the bolts to 60 N·m (44 lb ft).
- Install the torque converter cover to the transmission.
 
- Install the bolts securing the torque converter cover.
 
Tighten
Tighten the bolts to 33 N·m (24 lb ft).
- Install the vent hose to the wiring harness using a new tie strap.
 
- Connect the wiring harness to the wiring loom on the left side of the transmission.
 
- Connect the electrical harness to the park/neutral position switch, the input speed sensor, and the output speed sensor.
 
- Install the range selector cable to the transmission range selector lever ball stud and bracket. Refer to 
Range Selector Lever Cable Replacement
 .
 
- Install the transfer case, if equipped. Refer to 
Transfer Case Assembly Replacement
 for the
NVG 149-NP (One Speed Automatic) Transfer Case or 
Transfer Case Assembly Replacement
 for the NVG 236/246-NP8 (Two Speed Automatic) Transfer Case.
 
- Install the transmission mount. Refer to 
Transmission Mount Replacement
 .
 
- Install the exhaust manifold pipe. Refer to 
Exhaust Manifold Pipe Replacement
 .
 
- Install the transmission support. Refer to 
Transmission Support Replacement
 .
 
- Remove the transmission jack.
 
- Install the rear propeller shaft. Refer to 
One-Piece Propeller Shaft Replacement
 or 
Two-Piece Propeller Shaft Replacement
 .
 
- Connect the transmission oil cooler lines to the transmission. Refer to 
Transmission Fluid Cooler Hose/Pipe Quick-Connect Fitting Disconnection and Connection
 .
 
- Install the transmission heat shield.
 
- Install the bolts securing the heat shield to the transmission.
 
Tighten
Tighten the bolts to 17 N·m (13 lb ft).
- Lower the vehicle.
 
- Fill the transmission to the proper level. Refer to 
Transmission Fluid Check
 .
 
Important: It is recommended that transmission adaptive pressure (TAP) information be reset.
Resetting the TAP values using a scan tool will erase all learned values in all cells. As a result, the engine control module
(ECM), powertrain control module (PCM) or transmission control module (TCM) will need to relearn TAP values. Transmission performance may be affected as new TAP values are learned.
- Reset the TAP values. Refer to 
Transmission Adaptive Functions
 .