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For 1990-2009 cars only

Transmission Replacement 6L50 All Wheel Drive

Note: NEW cooler pipe O-rings and torque converter bolts will be required each time the transmission is removed and installed.

Removal Procedure

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Remove the exhaust system. Refer to Exhaust System Replacement.
  3. Remove the propeller shaft. Refer to Rear Propeller Shaft Replacement.

  4. Object Number: 1827761  Size: SH
  5. Disconnect the shift linkage from the transmission.

  6. Object Number: 1850371  Size: SH
  7. Disconnect the transmission wiring harness connector (5) from the transmission by releasing the locking mechanism and rotating the latch counterclockwise. Refer to Automatic Transmission Inline 16-Way Connector Description.
  8. Disconnect the wiring harness retainers (4) from the transmission.
  9. Remove the transmission vent hose from the retaining clips (6) on the transmission mount assembly.
  10. Remove the front air deflector. Refer to Front Air Deflector Replacement.
  11. Remove the transmission fluid cooler lines form the cooler line retainer bracket.
  12. Place an oil drain pan under the transmission fluid cooler pipes.

  13. Object Number: 1710028  Size: SH
  14. Remove the transmission fluid cooler pipes from the transmission, and position aside. Refer to Transmission Fluid Cooler Pipe Replacement - Rear.
  15. Remove and discard the O-rings. Do NOT reuse the O-rings.
  16. Plug the open outlet ports to prevent fluid loss and contamination.

  17. Object Number: 830376  Size: SH
  18. Remove the transmission close out plug.
  19. Mark the torque converter to flexplate/flywheel orientation to ensure proper realignment.
  20. Remove the torque converter bolt close out cover from the engine block.

  21. Object Number: 1644597  Size: SH
  22. Repeat the following steps for all 3 torque converter bolts:
  23. 17.1. Rotate the harmonic balancer center bolt clockwise ONLY, in order to align the torque converter bolt with the access hole.
    17.2. Remove and discard the torque converter bolt.

    Object Number: 907425  Size: SH
  24. Disconnect the intermediate shaft from the power steering gear. Refer to Steering Gear Replacement.

  25. Object Number: 1850365  Size: SH
  26. Support the transmission with a suitable transmission jack.
  27. Remove the transmission mount assembly. Refer to Transmission Mount Replacement.
  28. Support the rear of the front frame with adjustable jack stands.
  29. Remove the bolts at the rear of the front frame.
  30. Loosen the bolts at the front of the front frame two turns but do NOT remove the bolts.
  31. Lower the rear of the front frame and the transmission.

  32. Object Number: 1850371  Size: SH
  33. Lower the transmission and remove the vent hose (2) from the vent tube.
  34. Position the wire harness and vent tube aside.

  35. Object Number: 830369  Size: SH
  36. Remove the transfer case. Refer to Transfer Case Assembly Replacement.

  37. Object Number: 1850362  Size: SH
  38. Remove the top two transmission mounting bolts (1).

  39. Object Number: 1644591  Size: SH
  40. Remove the right side transmission mounting bolts.

  41. Object Number: 1850360  Size: SH
  42. Remove the left side transmission mounting bolts.
  43. Pull the transmission free from the engine dowels.
  44. Separate the transmission from the engine approximately 25.4 mm (1 in) to clear the starter drive nose cone.
  45. Note: Ensure clearance is maintained between the transmission and the following:

       • The starter drive nose cone
       • The catalytic converters
       • The oxygen sensors
       • The wiring harnesses
       • The cooler pipes

  46. Carefully lower the transmission from the vehicle.
  47. Flush the transmission oil cooler if necessary. Refer to Transmission Fluid Cooler Flushing and Flow Test.

Installation Procedure

    Note: Ensure clearance is maintained between the transmission and the following:

       • The starter drive nose cone
       • The catalytic converters
       • The oxygen sensors
       • The wiring harnesses
       • The cooler pipes

  1. Using the transmission jack, carefully raise the transmission to meet the engine.

  2. Object Number: 1850360  Size: SH
  3. Align the transmission with the engine dowels.
  4. Install the left side transmission mounting bolts. Do not tighten at this time.

  5. Object Number: 1644591  Size: SH
  6. Install the right side transmission mounting bolts.
  7. Caution: Refer to Fastener Caution in the Preface section.

  8. Tighten the right and left side transmission mounting bolts and tighten to 50 N·m (37 lb ft).

  9. Object Number: 1850362  Size: SH
  10. Install the top two transmission mounting bolts (1) and tighten to 50 N·m (37 lb ft).

  11. Object Number: 830369  Size: SH
  12. Install the transfer case. Refer to Transfer Case Assembly Replacement.

  13. Object Number: 1850371  Size: SH
  14. Remove the support stand from under the engine oil pan.
  15. Using the transmission jack. Lower the engine and transmission assembly only enough to gain access to the vent hose tube.
  16. Install the vent hose (2) to the vent tube.
  17. Position the engine wiring harness to the original location.
  18. Raise the transmission to the installed position.
  19. Install the bolts at the rear of the front frame and properly torque all frame bolts. Refer to Front Frame Replacement for proper frame bolt tightening information.

  20. Object Number: 1850365  Size: SH
  21. Install the transmission mount assembly. Refer to Transmission Mount Replacement.
  22. Remove the transmission jack.

  23. Object Number: 907425  Size: SH
  24. Connect the intermediate shaft to the power steering gear. Refer to Steering Gear Replacement.
  25. Align the torque converter to flexplate/flywheel orientation marks made during the removal procedure.

  26. Object Number: 1644597  Size: SH

    Note: Torque converter bolts are self locking and must be replaced with NEW torque converter bolts every time the bolts are removed.

  27. Complete the following steps for all 3 torque converter bolts:
  28. 18.1. Rotate the harmonic balancer center bolt clockwise ONLY, in order to align the torque converter bolt holes in the flexplate/flywheel with the access hole in the engine block.
    18.2. To aid in alignment of the torque converter to the flexplate/flywheel. Install all 3 NEW torque converter bolts before fully tightening then tighten to 63 N·m (46 lb ft).

    Object Number: 830376  Size: SH
  29. Install the torque converter bolt close out cover to the engine block.
  30. Install the transmission close out plug.

  31. Object Number: 1710028  Size: SH
  32. Place NEW O-rings over the transmission fluid cooler pipes.
  33. Install the transmission fluid cooler pipes to the transmission. Refer to Transmission Fluid Cooler Pipe Replacement - Rear.
  34. Install the transmission fluid cooler lines to the cooler line retainer bracket.
  35. Install the front air deflector. Refer to Front Air Deflector Replacement.

  36. Object Number: 1850371  Size: SH
  37. Install the transmission vent hose to the retaining clips (6) on the transmission mount assembly.
  38. Install the wiring harness retainers (4) to the transmission.
  39. Connect the transmission wiring harness connector (5) to the transmission by rotating the locking latch clockwise.

  40. Object Number: 1827761  Size: SH
  41. Install the shift linkage to the transmission. Refer to Transmission Control Replacement.
  42. Install the propeller shaft. Refer to Rear Propeller Shaft Replacement.
  43. Install the exhaust system. Refer to Exhaust System Replacement.
  44. Lower the vehicle.
  45. Check the transmission fluid level and fill if necessary. Refer to Transmission Fluid Check.
  46. Adjust the shift control linkage. Refer to Shift Control Linkage Adjustment.

Transmission Final Test and Inspection

Complete the following procedure after the transmission is installed in the vehicle:

  1. With the ignition OFF or disconnected, crank the engine several times. Listen for any unusual noises or evidence that any parts are binding.
  2. Start the engine and listen for abnormal conditions.
  3. While the engine continues to idle, raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  4. Inspect for fluid leaks while the engine is idling.
  5. Perform a final inspection for the proper fluid level.
  6. Lower the vehicle.
  7. Note: 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 ECM, PCM or TCM will need to relearn TAP values. Transmission performance may be affected as new TAP values are learned.

  8. Reset the TAP values. Refer to Transmission Adaptive Functions.
  9. Road test the vehicle.
  10. Calibrate the transmission control module (TCM). Refer to Control Module References.

Transmission Replacement 6L50 Rear Wheel Drive

Note: NEW cooler pipe O-rings and torque converter bolts will be required each time the transmission is removed and installed.

Removal Procedure

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Remove the exhaust system. Refer to Exhaust System Replacement.
  3. Remove the propeller shaft. Refer to Rear Propeller Shaft Replacement.

  4. Object Number: 1841192  Size: SH
  5. Disconnect the shift linkage from the transmission.

  6. Object Number: 1850370  Size: SH
  7. Disconnect the transmission wiring harness connector (5) from the transmission by releasing the locking mechanism and rotating the latch counterclockwise. Refer to Automatic Transmission Inline 16-Way Connector Description.
  8. Disconnect the wiring harness retainers (4) from the transmission.
  9. Remove the transmission vent hose from the retaining clips (6) on the transmission mount assembly.
  10. Remove the front air deflector. Refer to Front Air Deflector Replacement.
  11. Remove the transmission fluid cooler lines form the cooler line retainer bracket.
  12. Place an oil drain pan under the transmission fluid cooler pipes.

  13. Object Number: 1710028  Size: SH
  14. Remove the transmission fluid cooler pipes from the transmission, and position aside. Refer to Transmission Fluid Cooler Pipe Replacement - Rear.
  15. Remove and discard the O-rings. Do NOT reuse the O-rings.
  16. Plug the open outlet ports to prevent fluid loss and contamination.

  17. Object Number: 830376  Size: SH
  18. Remove the transmission close out plug.
  19. Mark the torque converter to flexplate/flywheel orientation to ensure proper realignment.
  20. Remove the torque converter bolt close out cover from the engine block.

  21. Object Number: 1644597  Size: SH
  22. Repeat the following steps for all 3 torque converter bolts:
  23. 17.1. Rotate the harmonic balancer center bolt clockwise ONLY, in order to align the torque converter bolt with the access hole.
    17.2. Remove and discard the torque converter bolt.

    Object Number: 907425  Size: SH
  24. Disconnect the intermediate shaft from the power steering gear. Refer to Steering Gear Replacement.
  25. Support the transmission with a suitable transmission jack.

  26. Object Number: 1649726  Size: SH
  27. Remove the transmission mount assembly. Refer to Transmission Mount Replacement.
  28. Support the rear of the front frame with adjustable jack stands.
  29. Remove the bolts at the rear of the front frame.
  30. Loosen the bolts at the front of the front frame two turns but do NOT remove the bolts.
  31. Lower the rear of the front frame and the transmission.

  32. Object Number: 1850370  Size: SH
  33. Remove the vent hose (2) from the vent tube.
  34. Position the wire harness and vent tube aside.

  35. Object Number: 1850362  Size: SH
  36. Remove the top two transmission mounting bolts (1).

  37. Object Number: 1644591  Size: SH
  38. Remove the right side transmission mounting bolts.

  39. Object Number: 1850360  Size: SH
  40. Remove the left side transmission mounting bolts.
  41. Pull the transmission free from the engine dowels.
  42. Separate the transmission from the engine approximately 25.4 mm (1 in) to clear the starter drive nose cone.
  43. Note: Ensure clearance is maintained between the transmission and the following:

       • The starter drive nose cone
       • The catalytic converters
       • The oxygen sensors
       • The wiring harnesses
       • The cooler pipes

  44. Carefully lower the transmission from the vehicle.
  45. Flush the transmission oil cooler if necessary. Refer to Transmission Fluid Cooler Flushing and Flow Test.

Installation Procedure

    Note: Ensure clearance is maintained between the transmission and the following:

       • The starter drive nose cone
       • The catalytic converters
       • The oxygen sensors
       • The wiring harnesses
       • The cooler pipes

  1. Using the transmission jack, carefully raise the transmission to meet the engine.

  2. Object Number: 1850360  Size: SH
  3. Align the transmission with the engine dowels.
  4. Install the left side transmission mounting bolts. Do not tighten at this time.

  5. Object Number: 1644591  Size: SH
  6. Install the right side transmission mounting bolts.
  7. Caution: Refer to Fastener Caution in the Preface section.

  8. Tighten the right and left side transmission mounting bolts and tighten to 50 N·m (37 lb ft).

  9. Object Number: 1850362  Size: SH
  10. Install the top two transmission mounting bolts (1) and tighten to 50 N·m (37 lb ft).

  11. Object Number: 1850370  Size: SH
  12. Install the vent hose (2) to the vent tube.
  13. Position the engine wiring harness to the original location.
  14. Raise the transmission and front frame to the installed position.
  15. Install the bolts at the rear of the front frame and properly torque all frame bolts. Refer to Front Frame Replacement for proper frame bolt tightening information.

  16. Object Number: 1649726  Size: SH
  17. Install the transmission mount assembly. Refer to Transmission Mount Replacement.
  18. Remove the jacks from under the transmission and frame.

  19. Object Number: 907425  Size: SH
  20. Connect the intermediate shaft to the power steering gear. Refer to Steering Gear Replacement.
  21. Align the torque converter to flexplate/flywheel orientation marks made during the removal procedure.

  22. Object Number: 1644597  Size: SH

    Note: Torque converter bolts are self locking and must be replaced with NEW torque converter bolts every time the bolts are removed.

  23. Complete the following steps for all 3 torque converter bolts:
  24. 15.1. Rotate the harmonic balancer center bolt clockwise ONLY, in order to align the torque converter bolt holes in the flexplate/flywheel with the access hole in the engine block.
    15.2. To aid in alignment of the torque converter to the flexplate/flywheel. Install all 3 NEW torque converter bolts before fully tightening.

    Tighten the torque converter bolts to 63 N·m (46 lb ft).


    Object Number: 830376  Size: SH
  25. Install the torque converter bolt close out cover to the engine block.
  26. Install the transmission close out plug.

  27. Object Number: 1710028  Size: SH
  28. Place NEW O-rings over the transmission fluid cooler pipes.
  29. Install the transmission fluid cooler pipes to the transmission. Refer to Transmission Fluid Cooler Pipe Replacement - Rear.
  30. Install the transmission fluid cooler lines to the cooler line retainer bracket.
  31. Install the front air deflector. Refer to Front Air Deflector Replacement.

  32. Object Number: 1850370  Size: SH
  33. Install the transmission vent hose to the retaining clips (6) on the transmission mount assembly.
  34. Install the wiring harness retainers (4) to the transmission.
  35. Connect the transmission wiring harness connector (5) to the transmission by rotating the locking latch clockwise.

  36. Object Number: 1841192  Size: SH
  37. Install the shift linkage to the transmission. Refer to Transmission Control Replacement.
  38. Install the propeller shaft. Refer to Rear Propeller Shaft Replacement.
  39. Install the exhaust system. Refer to Exhaust System Replacement.
  40. Lower the vehicle.
  41. Check the transmission fluid level and fill if necessary. Refer to Transmission Fluid Check.
  42. Adjust the shift control linkage. Refer to Shift Control Linkage Adjustment.

Transmission Final Test and Inspection

Complete the following procedure after the transmission is installed in the vehicle:

  1. With the ignition OFF or disconnected, crank the engine several times. Listen for any unusual noises or evidence that any parts are binding.
  2. Start the engine and listen for abnormal conditions.
  3. While the engine continues to idle, raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  4. Inspect for fluid leaks while the engine is idling.
  5. Perform a final inspection for the proper fluid level.
  6. Lower the vehicle.
  7. Note: 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 ECM, PCM or TCM will need to relearn TAP values. Transmission performance may be affected as new TAP values are learned.

  8. Reset the TAP values. Refer to Transmission Adaptive Functions.
  9. Road test the vehicle.
  10. Calibrate the transmission control module (TCM). Refer to Control Module References.

Transmission Replacement 6L80

Removal Procedure

    Note: 

       • NEW cooler pipe O-rings and torque converter bolts will be required each time the transmission is removed and installed.
       • The top two transmission mounting bolts must be accessed from the engine compartment.


    Object Number: 1652890  Size: SH
  1. Remove the front and rear sections of the supercharger inlet duct assembly. Refer to Supercharger Inlet Duct Assembly Replacement.

  2. Object Number: 1644602  Size: SH
  3. Remove the wire harness (1) from the wire harness bracket.

  4. Object Number: 1644605  Size: SH
  5. Remove the top two transmission mounting bolts (1).

  6. Object Number: 1841192  Size: SH
  7. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  8. Remove the exhaust system. Refer to Exhaust System Replacement.
  9. Remove the propeller shaft. Refer to Rear Propeller Shaft Replacement.
  10. Disconnect the shift linkage from the transmission.

  11. Object Number: 1645250  Size: SH
  12. Disconnect the transmission wiring harness connector (8) from the transmission by releasing the locking mechanism and rotating the latch counterclockwise. Refer to Automatic Transmission Inline 16-Way Connector Description.
  13. Disconnect the wiring harness retainers (7, 9) from the transmission.
  14. Remove the transmission vent hose from the retaining clips (1, 2) on the transmission mount assembly.
  15. Remove the front air deflector. Refer to Front Air Deflector Replacement.
  16. Remove the transmission fluid cooler lines form the cooler line retainer bracket.
  17. Place an oil drain pan under the transmission fluid cooler pipes.

  18. Object Number: 1710028  Size: SH
  19. Remove the transmission fluid cooler pipes from the transmission, and position aside. Refer to Transmission Fluid Cooler Pipe Replacement - Rear.
  20. Remove and discard the O-rings. Do NOT reuse the O-rings.
  21. Plug the open outlet ports to prevent fluid loss and contamination.

  22. Object Number: 830376  Size: SH
  23. Remove the transmission close out plug.
  24. Mark the torque converter to flexplate/flywheel orientation to ensure proper realignment.
  25. Remove the torque converter bolt close out cover from the engine block.

  26. Object Number: 1644597  Size: SH
  27. Repeat the following steps for all 3 torque converter bolts:
  28. 20.1. Rotate the harmonic balancer center bolt clockwise ONLY, in order to align the torque converter bolt with the access hole.
    20.2. Remove and discard the torque converter bolt.

    Object Number: 1649726  Size: SH
  29. Support the transmission with a suitable transmission jack.
  30. Remove the transmission mount assembly. Refer to Transmission Mount Replacement.

  31. Object Number: 1645250  Size: SH
  32. Lower the transmission and remove the vent hose (5) from the vent tube.
  33. Position the wire harness and vent tube aside.

  34. Object Number: 830398  Size: SH
  35. Using the transmission jack. Raise the engine and transmission assembly to the normal position.
  36. Place a support stand under the rear of the engine oil pan to keep the engine level while removing the transmission.

  37. Object Number: 1644591  Size: SH
  38. Remove the right side transmission mounting bolts.

  39. Object Number: 1850360  Size: SH
  40. Remove the left side transmission mounting bolts.
  41. Pull the transmission free from the engine dowels.
  42. Separate the transmission from the engine approximately 25.4 mm (1 in) to clear the starter drive nose cone.
  43. Note: Ensure clearance is maintained between the transmission and the following:

       • The starter drive nose cone
       • The catalytic converters
       • The oxygen sensors
       • The wiring harnesses
       • The cooler pipes

  44. Carefully lower the transmission from the vehicle.
  45. Flush the transmission oil cooler if necessary. Refer to Transmission Fluid Cooler Flushing and Flow Test.

Installation Procedure

    Note: Ensure clearance is maintained between the transmission and the following:

       • The starter drive nose cone
       • The catalytic converters
       • The oxygen sensors
       • The wiring harnesses
       • The cooler pipes

  1. Using the transmission jack, carefully raise the transmission to meet the engine.

  2. Object Number: 1850360  Size: SH
  3. Align the transmission with the engine dowels.
  4. Install the left side transmission mounting bolts. Do not tighten at this time.

  5. Object Number: 1644591  Size: SH
  6. Install the right side transmission mounting bolts.
  7. Caution: Refer to Fastener Caution in the Preface section.

  8. Tighten the right and left side transmission mounting bolts to 50 N·m (37 lb ft).

  9. Object Number: 1645250  Size: SH
  10. Remove the support stand from under the engine oil pan.
  11. Using the transmission jack. Lower the engine and transmission assembly only enough to gain access to the vent hose tube.
  12. Install the vent hose (5) to the vent tube.
  13. Position the engine wiring harness to the original location.
  14. Raise the transmission to the installed position.

  15. Object Number: 1649726  Size: SH
  16. Install the transmission mount assembly. Refer to Transmission Mount Replacement.
  17. Remove the transmission jack.
  18. Align the torque converter to flexplate/flywheel orientation marks made during the removal procedure.

  19. Object Number: 1644597  Size: SH

    Note: Torque converter bolts are self locking and must be replaced with NEW torque converter bolts every time the bolts are removed.

  20. Complete the following steps for all 3 torque converter bolts:
  21. 14.1. Rotate the harmonic balancer center bolt clockwise ONLY, in order to align the torque converter bolt holes in the flexplate/flywheel with the access hole in the engine block.
    14.2. To aid in alignment of the torque converter to the flexplate/flywheel. Install all 3 NEW torque converter bolts before fully tightening.

    Tighten the torque converter bolts to 63 N·m (46 lb ft).


    Object Number: 830376  Size: SH
  22. Install the torque converter bolt close out cover to the engine block.
  23. Install the transmission close out plug.

  24. Object Number: 1710028  Size: SH
  25. Place NEW O-rings over the transmission fluid cooler pipes.
  26. Install the transmission fluid cooler pipes to the transmission. Refer to Transmission Fluid Cooler Pipe Replacement - Rear.
  27. Install the transmission fluid cooler lines to the cooler line retainer bracket.
  28. Install the front air deflector. Refer to Front Air Deflector Replacement.

  29. Object Number: 1645250  Size: SH
  30. Install the transmission vent hose to the retaining clips (1, 2) on the transmission mount assembly.
  31. Install the wiring harness retainers (7, 9) to the transmission.
  32. Connect the transmission wiring harness connector (8) to the transmission by rotating the locking latch clockwise.

  33. Object Number: 1841192  Size: SH
  34. Install the shift linkage to the transmission. Refer to Transmission Control Replacement.
  35. Install the propeller shaft. Refer to Rear Propeller Shaft Replacement.
  36. Install the exhaust system. Refer to Exhaust System Replacement.
  37. Lower the vehicle.

  38. Object Number: 1644605  Size: SH
  39. Install the top two transmission mounting bolts (1) and tighten to 50 N·m (37 lb ft).

  40. Object Number: 1644602  Size: SH
  41. Install the wire harness (1) to the wire harness bracket.

  42. Object Number: 1652890  Size: SH
  43. Install the front and rear sections of the supercharger inlet duct assembly. Refer to Supercharger Inlet Duct Assembly Replacement.
  44. Check the transmission fluid level and fill if necessary. Refer to Transmission Fluid Check.
  45. Adjust the shift control linkage. Refer to Shift Control Linkage Adjustment.

Transmission Final Test and Inspection

Complete the following procedure after the transmission is installed in the vehicle:

  1. With the ignition OFF or disconnected, crank the engine several times. Listen for any unusual noises or evidence that any parts are binding.
  2. Start the engine and listen for abnormal conditions.
  3. While the engine continues to idle, raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  4. Inspect for fluid leaks while the engine is idling.
  5. Perform a final inspection for the proper fluid level.
  6. Lower the vehicle.
  7. Note: 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 ECM, PCM or TCM will need to relearn TAP values. Transmission performance may be affected as new TAP values are learned.

  8. Reset the TAP values. Refer to Transmission Adaptive Functions.
  9. Road test the vehicle.
  10. Calibrate the transmission control module (TCM). Refer to Control Module References.