GM Service Manual Online
For 1990-2009 cars only

Transmission Replacement 4WD

Special Tools

J 42371 Hydraulic Clutch Line Separator

Removal Procedure

  1. Remove the control lever and boot. Refer to Control Lever and/or Boot Replacement.
  2. Drain the transmission fluid if necessary. Refer to Transmission Fluid Replacement.
  3. Remove the transfer case assembly. Refer to Transfer Case Assembly Replacement.

  4. Object Number: 1302107  Size: SH
  5. Using the J 42371 , push back on the white plastic sleeve on the quick connect in order to separate the hydraulic clutch line from the clutch actuator quick connect.
  6. It is not necessary to plug the lower hose end or slave cylinder fitting as they are equipped with check valves, only minimal fluid loss may be experienced.


    Object Number: 1302110  Size: SH
  7. Disconnect the following engine wiring harness electrical connectors:
  8. • Backup lamp switch (1)
    • Oxygen sensor (2)
  9. Disconnect the engine wiring harness clip (3) from the clip bracket, and position the harness over the transmission.

  10. Object Number: 1302108  Size: SH
  11. Disconnect the vehicle speed sensor (VSS) electrical connector (2)
  12. Disconnect the engine wiring harness clips (1) from the clip brackets, and position the harness aside.

  13. Object Number: 1302111  Size: SH
  14. Remove the nuts securing the fuel hose/pipe brackets to the transmission, and position aside.

  15. Object Number: 1302112  Size: SH
  16. Support and secure the transmission using a suitable transmission jack.
  17. Remove the transmission crossmember. Refer to Transmission Support Crossmember Replacement.

  18. Object Number: 1302113  Size: SH
  19. Remove the service slot plug.

  20. Object Number: 1302117  Size: SH
  21. Remove the 9 transmission mounting bolts.

  22. Object Number: 1302115  Size: SH
  23. Remove the remaining transmission mounting bolts (2).
  24. Note: Do not allow the transmission to hang from the clutch assembly.

  25. Pull the transmission straight back off the clutch hub splines.
  26. Note: Ensure clearance is maintained between the transmission and the following:

       • The catalytic converter
       • The clutch assembly
       • The engine wiring harness
       • The fuel hose/pipe brackets
       • The heater pipe

  27. Using the transmission jack, carefully lower the transmission from the vehicle.

Installation Procedure

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

       • The catalytic converter
       • The clutch assembly
       • The engine wiring harness
       • The fuel hose/pipe brackets
       • The heater pipe

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

  2. Object Number: 1302115  Size: SH

    Note: Do not allow the transmission to hang from the clutch assembly.

  3. Align the transmission with the engine dowels (1).
  4. Caution: Refer to Fastener Caution in the Preface section.

  5. Install the 2 transmission mounting bolts (2) and tighten to 50 N·m (37 lb ft).

  6. Object Number: 1302117  Size: SH

    Note: 

       • Ensure the studded mounting bolts (2) are located in the correct position.
       • The heater pipe (1) must be secured with the 2 upper mounting bolts.

  7. Install the remaining transmission mounting bolts and tighten to 50 N·m (37 lb ft).

  8. Object Number: 1302113  Size: SH
  9. Install the service slot plug.
  10. Install the transmission crossmember. Refer to Transmission Support Crossmember Replacement.

  11. Object Number: 1302112  Size: SH
  12. Remove the transmission jack from under the vehicle.

  13. Object Number: 1302111  Size: SH
  14. Install the nuts securing the fuel hose/pipe brackets to the transmission. Tighten the fuel hose/pipe brackets nuts to 20 N·m (15 lb ft).

  15. Object Number: 1302108  Size: SH
  16. Connect the VSS electrical connector (2)
  17. Connect the engine wiring harness clips (1) to the clip brackets.
  18. Lay the engine wiring harness over the transmission.

  19. Object Number: 1302110  Size: SH
  20. Connect the following engine wiring harness electrical connectors:
  21. • Backup lamp switch (1)
    • Oxygen sensor (2)
  22. Connect the engine wiring harness clip (3) to the clip bracket.

  23. Object Number: 1302134  Size: SH

    Note: Ensure the clutch hydraulic hose does not come in contact with any sharp or potential hot surfaces.

  24. Push the clutch hydraulic hose quick connect fitting (2) into the clutch slave cylinder, until a "click" is heard.
  25. Tug gently on the clutch hydraulic hose to ensure proper retention into the clutch slave cylinder.
  26. Install the transfer case assembly. Refer to Transfer Case Assembly Replacement.
  27. Fill the transmission fluid if removed. Refer to Transmission Fluid Replacement.
  28. Install the control lever and boot. Refer to Control Lever and/or Boot Replacement.

Transmission Final Test and Inspection

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

  1. With the ignition OFF or disconnected and clutch pedal depressed, crank the engine several times. Listen for any unusual noises or evidence that any parts are binding.
  2. Place the transmission in neutral, start the engine and listen for any unusual noises or evidence that any parts are binding.
  3. Turn OFF the ignition.
  4. Perform a final inspection for the proper fluid level. Refer to Transmission Fluid Replacement.
  5. Road test the vehicle.

Transmission Replacement RWD

Special Tools

J 42371 Hydraulic Clutch Line Separator

Removal Procedure

  1. Remove the control lever and boot. Refer to Control Lever and/or Boot Replacement.
  2. Drain the transmission fluid if necessary. Refer to Transmission Fluid Replacement.
  3. Remove the rear propeller shaft. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement.

  4. Object Number: 1302107  Size: SH
  5. Using the J 42371 , push back on the white plastic sleeve on the quick connect in order to separate the hydraulic clutch line from the clutch actuator quick connect.
  6. It is not necessary to plug the lower hose end or slave cylinder fitting as they are equipped with check valves, only minimal fluid loss may be experienced.


    Object Number: 1302110  Size: SH
  7. Disconnect the following engine wiring harness electrical connectors:
  8. • Backup lamp switch (1)
    • Oxygen sensor (2)
  9. Disconnect the engine wiring harness clip (3) from the clip bracket, and position the harness over the transmission.

  10. Object Number: 1302108  Size: SH
  11. Disconnect the vehicle speed sensor (VSS) electrical connector (2)
  12. Disconnect the engine wiring harness clips (1) from the clip brackets, and position the harness aside.

  13. Object Number: 1302111  Size: SH
  14. Remove the nuts securing the fuel hose/pipe brackets to the transmission, and position aside.

  15. Object Number: 1302112  Size: SH
  16. Support and secure the transmission using a suitable transmission jack.
  17. Remove the transmission crossmember. Refer to Transmission Support Crossmember Replacement.

  18. Object Number: 1302113  Size: SH
  19. Remove the service slot plug.

  20. Object Number: 1302117  Size: SH
  21. Remove the 9 transmission mounting bolts.

  22. Object Number: 1302115  Size: SH
  23. Remove the remaining transmission mounting bolts (2).
  24. Note: Do not allow the transmission to hang from the clutch assembly.

  25. Pull the transmission straight back off the clutch hub splines.
  26. Note: Ensure clearance is maintained between the transmission and the following:

       • The catalytic converter
       • The clutch assembly
       • The engine wiring harness
       • The fuel hose/pipe brackets
       • The heater pipe

  27. Using the transmission jack, carefully lower the transmission from the vehicle.

Installation Procedure

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

       • The catalytic converter
       • The clutch assembly
       • The engine wiring harness
       • The fuel hose/pipe brackets
       • The heater pipe

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

  2. Object Number: 1302115  Size: SH

    Note: Do not allow the transmission to hang from the clutch assembly.

  3. Align the transmission with the engine dowels (1).
  4. Caution: Refer to Fastener Caution in the Preface section.

  5. Install the 2 transmission mounting bolts (2) and tighten to 50 N·m (37 lb ft).

  6. Object Number: 1302117  Size: SH

    Note: 

       • Ensure the studded mounting bolts (2) are located in the correct position.
       • The heater pipe (1) must be secured with the 2 upper mounting bolts.

  7. Install the remaining transmission mounting bolts and tighten to 50 N·m (37 lb ft).

  8. Object Number: 1302113  Size: SH
  9. Install the service slot plug.
  10. Install the transmission crossmember. Refer to Transmission Support Crossmember Replacement.

  11. Object Number: 1302112  Size: SH
  12. Remove the transmission jack from under the vehicle.

  13. Object Number: 1302111  Size: SH
  14. Install the nuts securing the fuel hose/pipe brackets to the transmission.
  15. Tighten the fuel hose/pipe brackets nuts to 20 N·m (15 lb ft).


    Object Number: 1302108  Size: SH
  16. Connect the VSS electrical connector (2)
  17. Connect the engine wiring harness clips (1) to the clip brackets.
  18. Lay the engine wiring harness over the transmission.

  19. Object Number: 1302110  Size: SH
  20. Connect the following engine wiring harness electrical connectors:
  21. • Backup lamp switch (1)
    • Oxygen sensor (2)
  22. Connect the engine wiring harness clip (3) to the clip bracket.

  23. Object Number: 1302134  Size: SH

    Note: Ensure the clutch hydraulic hose does not come in contact with any sharp or potential hot surfaces.

  24. Push the clutch hydraulic hose quick connect fitting (2) into the clutch slave cylinder, until a "click" is heard.
  25. Tug gently on the clutch hydraulic hose to ensure proper retention into the clutch slave cylinder.
  26. Install the rear propeller shaft. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement.
  27. Fill the transmission fluid if removed. Refer to Transmission Fluid Replacement.
  28. Install the control lever and boot. Refer to Control Lever and/or Boot Replacement.

Transmission Final Test and Inspection

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

  1. With the ignition OFF or disconnected and clutch pedal depressed, crank the engine several times. Listen for any unusual noises or evidence that any parts are binding.
  2. Place the transmission in neutral, start the engine and listen for any unusual noises or evidence that any parts are binding.
  3. Turn OFF the ignition.
  4. Perform a final inspection for the proper fluid level. Refer to Transmission Fluid Replacement.
  5. Road test the vehicle.