GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2002 🢒 Venture Ext. 🢒 Engine 🢒 Engine Mechanical - 3.4L 🢒 Transfer Case Assembly Replacement

Removal Procedure
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove propeller shaft. Refer to Propeller Shaft Replacement in Propeller Shaft.

    3. Important: Transmission oil circulates between the transmission assembly and the transfer case differential carrier and three helical gear set. In situations where transmission related failures circulate fiber type debris, such as clutch friction disc material into the transfer case, the helical gear portion of the transfer case must be disassembled, cleaned, and inspected for damage. In situations where transmission or transfer case related failures circulate metal type debris, such as bearing material, repair or overhaul of both components may be required.


    Object Number: 630583 Size: SH
  3. Remove the drain plug (1) and washer from the extension housing. Allow the gear oil to drain.

    4. Object Number: 630590 Size: SH
  4. Remove the drain plug (1) and washer from the case. Allow the transmission fluid to drain.
  5. Disconnect the electrical connector from the speed sensor.

    6. Object Number: 766361 Size: SH
  6. Remove the transfer case lower brace bolts.
  7. Remove the transfer case lower brace.

    8. Object Number: 630581 Size: SH
  8. Disconnect the clamp from the extension housing vent hose coupling (1).
  9. Remove the bolt (3) retaining the vent hose bracket to the transfer case.
  10. Remove the vent hose coupling, vent hose (2), and bracket from the transfer case.
  11. Remove the transaxle. Refer to Transmission Replacement in Automatic Transaxle - 4T65-E.

    12. Object Number: 692584 Size: SH
  12. Remove the output shaft retaining ring (1).

    13. Object Number: 692586 Size: SH
  13. Rotate the transaxle 90 degrees.
  14. Remove the transfer case lower brace bolt (1).

    15. Object Number: 692583 Size: SH
  15. Rotate the transaxle 90 degrees to the installed position.
  16. Remove the transfer case side brace bolts (1, 2, 3, 4, 5). Remove the side brace (6).

    17. Object Number: 692593 Size: SH
  17. Remove the transfer case-to-transaxle bolts (1, 2, 3, 4, 5).

    18. Object Number: 692590 Size: SH

    Caution: This component weighs approximately 60 lbs. Personal injury may result if you lift the component improperly.

  18. Remove the transfer case assembly (1) from the transaxle (3). Note that the transaxle output shaft (2) withdraws from the transaxle with the transfer case assembly.
  19. Remove the output shaft (2). Refer to Transfer Case Removal in Automatic Transaxle - 4T65-E Unit Repair.

    20. Object Number: 692591 Size: SH
  20. Remove the transfer case O-ring seal (1) from the transfer case (2).

Installation Procedure

    Important: The end play clearance between the transmission and transfer case internal components is adjusted by selection of the proper size selective washer (located behind the transmission sun gear). The transmission-to-transfer case washer selection procedure must be performed each time a transmission and/or transfer case assembly or the internal components (excluding gaskets and seals) are replaced.

  1. Perform the transmission-to-transfer case end play check. Refer to Transmission to Transfer Case End Play Check in Automatic Transaxle - 4T65-E Unit Repair.

    2. Object Number: 692591 Size: SH
  2. Install the O-ring (1) seal to the transfer case.

    3. Object Number: 621064 Size: SH
  3. Rotate the transaxle so that the bottom pan is facing the floor.
  4. Install the transfer case assembly to the transaxle.

    5. Object Number: 677381 Size: SH
  5. Install the transfer case-to-transaxle bolts and tighten the bolts in the following sequence:

    6. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  6. Tighten the transfer case-to-transaxle bolts (1) and (2).

    7. Tighten

        • First pass 35 N·m (26 lb ft).
        • Final pass an additional 160 degrees.
  7. Tighten the transfer case-to-transaxle bolt (3).

    8. Tighten

        • First pass 35 N·m (26 lb ft).
        • Final pass an additional 70 degrees.
  8. Tighten the transfer case-to-transaxle bolts (4) and (5).

    9. Tighten
    Tighten the transfer case-to-transaxle bolts (4) and (5) to 40 N·m (30 lb ft).


    Object Number: 692583 Size: SH
  9. Install the transfer case side brace (6).
  10. Install the transfer case side brace-to-transaxle bolts. Hand tighten bolts.
  11. Tighten the bolts in the following sequence (1, 2, 3, 4, 5).

    12. Tighten
    Tighten transfer case side brace bolts to 47 N·m (35 lb ft).


    Object Number: 692586 Size: SH
  12. Rotate the transaxle 90 degrees.
  13. Install the transfer case lower brace-to-transaxle bolt (1).

    14. Tighten
    Tighten transfer case lower brace bolt to 47 N·m (35 lb ft).

  14. Install the output shaft to the transmission. Refer to Output Shaft Assemble in Automatic Transaxle 4T65-E Unit Repair.

    15. Object Number: 692584 Size: SH
  15. Install a new output shaft retaining ring (1).
  16. Install the transaxle. Refer to Transmission Replacement in Automatic Transaxle - 4T65-E.

    17. Object Number: 630581 Size: SH
  17. Install the vent hose (2) and coupling (1) to the extension housing.
  18. Connect the clamp to the vent hose coupling.
  19. Install the vent hose bracket and bolt/stud (3) to the transfer case.

    20. Tighten
    Tighten the bolt/stud to 10 N·m (106 lb in).

  20. Connect the electrical connector to the speed sensor.
  21. Install propeller shaft . Refer to Propeller Shaft Replacement in Propeller Shaft.

    22. Object Number: 766361 Size: SH
  22. Install the transfer case lower brace.
  23. Install the transfer case lower brace bolts.

    24. Tighten
    Tighten the brace bolts to 47 N·m (35 lb ft).


    Object Number: 630590 Size: SH
  24. Install the lubricant drain plug (1) and gasket to the case.

    25. Tighten
    Tighten the drain plug to 32 N·m (24 lb ft).

  25. Inspect the transmission fluid level. Refer to Transmission Fluid Check in Automatic Transaxle - 4T65-E.

    26. Object Number: 630583 Size: SH
  26. Install the lubricant drain plug (1) and gasket to the extension housing.

    27. Tighten
    Tighten the drain plug to 32 N·m (24 lb ft).

  27. Remove the extension housing fill plug (2) and gasket.
  28. Fill the extension housing with synthetic gear oil GM  P/N United States 12378514 GM P/N Canada 88901045. Refer to Transfer Case Fluid Replacement .
  29. Install the fill plug and gasket to the extension housing.

    30. Tighten
    Tighten the extension housing fill plug to 32 N·m (24 lb ft).

  30. Lower the vehicle.