GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 25018-A Input Clutch Spring Compressor Adapter
    • J 23327-1 Clutch Spring Compressor
    • J 36850 Transjelâ„¢
    • J 8001 Dial Indicator
    • J 26900-13 Magnetic Indicator Base

Disassembly Procedure


    Object Number: 412127  Size: SH
  1. Remove the snap ring from the clutch drum (2).

  2. Object Number: 163899  Size: SH
  3. Remove the following components:
  4. • The flange (9)
    • The discs (8)
    • The plates (7)

    Object Number: 412132  Size: SH
  5. Use a J 25018-A and J 23327 in order to compress the piston return springs (1).

  6. Object Number: 163899  Size: SH
  7. Remove the snap ring (6), exposing the retainer spring (5).

  8. Object Number: 412136  Size: SH
  9. Remove the following components:
  10. • The retainer spring
    • The 18 springs (1) 

    Object Number: 163618  Size: SH
  11. Remove the piston by applying compressed air into the oil passage.
  12. If the piston does not come out, use needle-nose pliers in order to remove the piston.


    Object Number: 163606  Size: SH
  13. Inspect the clutch piston:
  14. 7.1. Shake the piston in order to determine if the check ball is free.
    7.2. Apply low-pressure compressed air in order to determine if the valve leaks.

    Object Number: 163899  Size: SH
  15. Remove the O-rings (4) from the piston (3).
  16. Replace the oil seal rings (1) using the following procedure:
  17. 9.1. Slide the rings over the top of the shaft drum (2).
    9.2. Install the rings into the groove.
    9.3. Do not spread the ring ends.

Assembly Procedure

  1. Coat the new O-ring with J 36850 or equivalent.
  2. Install the new O-ring on the piston.
  3. Important: Do not damage the O-ring during piston installation.

  4. Install the piston into the forward clutch drum (2) .
  5. Verify that the cup side of the piston faces upward.


    Object Number: 412136  Size: SH
  6. Install the following components:
  7. 4.1. The 18 piston return springs (1) 
    4.2. The spring retainer

    Object Number: 412132  Size: SH
  8. Using J 25018-A and J 23327-1 , compress the return springs (1).
  9. Install the snap ring in the groove.
  10. Verify that the end gap on the snap ring is not aligned with the spring retainer claw.


    Object Number: 163899  Size: SH

    Important: Install the plates and the discs in order.

    Alternate the plates and the discs.

  11. Install the following components:
  12. 7.1. The plate (7)
    7.2. The disc (8)
    7.3. The plate (7)
    7.4. The disc (8)
    7.5. The plate (7)
    7.6. The disc (8)
    7.7. The plate (7)
    7.8. The disc (8)
    7.9. The flange (9)

    Install the flange with the flat end facing downward.

  13. Install the outer snap ring (10).
  14. Verify that the end gap of the snap ring is not aligned with any of the cutouts.

  15. Use compressed air in order to inspect the stroke of the forward clutch.

  16. Object Number: 163600  Size: SH
  17. Using J 8001 and J 26900-13 , apply compressed air into the oil passage with the shaft.
  18. Verify that the piston moves properly.
  19. If the piston does NOT move properly, disassemble and inspect the forward clutch.