GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Raise the vehicle and support. Refer to Lifting and Jacking the Vehicle .
  2. Place a drain pan under the transmission bottom pan in order to catch the fluid.
  3. Important: Removing the bottom pan on the Hydra-Matic 4T80-E only partially drains the transaxle fluid. The side cover and the torque converter hold the remaining fluid. To drain fluid from the side cover, remove the drain plug in the case after bottom pan removal. There is no need to drain the torque converter during most service procedures.

  4. Loosen the bottom pan bolts. Drain any fluid in the pan.

  5. Object Number: 97463  Size: SH
  6. Remove the bottom pan bolts, pan, and seal.
  7. Inspect the bottom pan for dents or nicks on the sealing surface. If damaged, replace.
  8. Important: The bottom pan seal is reusable. Replace with a new seal only if sealing surface is damaged.

  9. For proper sealing, clean and dry the bottom pan and the case sealing surfaces. In order to maintain proper bolt torque, the bolts and tapped holes in the case must be clean and dry.

  10. Object Number: 97465  Size: SH
  11. Remove the left and/or right scavenger screens.
  12. Remove the seals. Use a small screwdriver to pry the seals from the case. Do not score or damage the case.

Installation Procedure


    Object Number: 97465  Size: SH
  1. Install the new left and right scavenger seals.
  2. Install the new left and right scavenger screens.

  3. Object Number: 97463  Size: SH
  4. Install the bottom pan, seal, and bolts. Finger-tighten the bolts.
  5. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 15495  Size: SH
  6. Tighten the pan bolts 3 times to the proper specification, in the sequence shown:
  7. Tighten

    1. Tighten the pan bolts to 3 N·m (27 lb in).
    2. Tighten the pan bolts to 6 N·m (53 lb in).
    3. Tighten the pan bolts to 12 N·m (106 lb in).
  8. Lower the vehicle.
  9. Add DEXRON® VI transmission fluid as required. Refer to Transmission Fluid Check .