GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Refer to the following transmission component locator graphic as needed:


Object Number: 102589  Size: LH

(61)Rear Servo Cover Bolt
(62)Rear Servo Cover
(63)Rear Servo Cover Gasket
(64)Bottom Retaining Clip
(65)Rear Servo Piston
(66)Accumulator Piston Outer Ring Oil Seal
(67)Accumulator Piston Inner Ring Oil Seal
(68)Rear Accumulator Piston
(69)Reverse Servo Piston Seal
(70)Servo Piston Washer
(71)Rear Servo Spring
(72)Rear Piston Spring Retainer
(73)Rear Band Apply (Selective Pin)
(74)Rear Accumulator Spring

Remove the rear servo assembly from the transmission case.

Checking Procedure

Tools Required

    • J 21370-10
    • J 38737

    Object Number: 102596  Size: SH
  1. Place the J 21370-10 in the servo bore.

  2. Object Number: 102591  Size: SH
  3. Position the J 38737 over the bore with the hex nut facing the parking pawl linkage.
  4. Fasten the J 38737 with the two rear servo cover bolts.
  5. Tighten
    Tighten the bolts to 24 N·m (18 Ib ft).

    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. Make sure the J 21370-10 moves freely in the tool and the pin bore.
  7. In order to determine the correct pin length, apply torque to the nut on the gauge.
  8. Tighten
    Tighten the nut to 34 N·m (25 Ib ft).


    Object Number: 102600  Size: LH
  9. Select the correct band apply pin length.

Disassembly Procedure

Diassemble the Rear Servo Assembly. Refer to Low and Reverse Band Servo Assembly Disassemble

Assembly Procedure

Assemble the Rear Servo Assembly. Refer to Low and Reverse Band Servo Assembly Assemble

Installation Procedure

Install the Rear Servo Assembly. Refer to Low and Reverse Band Servo Assembly Installation