GM Service Manual Online
For 1990-2009 cars only

    Object Number: 678333  Size: SH
  1. Inspect the forward band servo components for the following conditions:
  2. • Damaged, worn or porous servo piston (16)
    • Damaged servo piston oil seal ring (18)
    • Damaged, worn or porous servo cover (13)
    • Damaged servo cover seal (14)
    • Broken or collapsed servo piston return spring (22)
    • Broken or collapsed servo piston cushion inner spring (65)
    • Broken or collapsed servo piston cushion outer spring (19)
    • Damaged or worn servo piston apply pin (21)

    Object Number: 678332  Size: SH
  3. Assemble the servo piston (16), the servo piston cushion outer spring (19), the servo piston cushion inner spring (65), the servo cushion spring retainer (20) and the servo piston apply pin (21).
  4. Install the servo pin retaining ring (15) onto the servo piston apply pin (21).
  5. Install the servo piston oil seal ring (18) onto the servo piston (16).
  6. Assemble the servo piston return spring (22) onto the servo assembly.

  7. Object Number: 48181  Size: SH
  8. Position the transmission so that the oil pan is facing up.
  9. Install the servo cover seal (14) onto the servo cover (13).
  10. Assemble the servo assembly (15-22) into the servo cover (13). Pivot the servo assembly (15-22) into the servo cover (13) in order to prevent the piston oil seal ring from being damaged.
  11. Install the servo and cover assembly (13-22) into the case.

  12. Object Number: 48177  Size: SH
  13. Using a long screwdriver, pry against the work bench in order to compress the forward band servo assembly (13).
  14. Hold the servo assembly compressed.
  15. 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.

  16. Install the 3 forward band servo cover bolts (12).
  17. Tighten
    Tighten the bolts to 12 N·m (106 lb in).

  18. Remove the long screwdriver.