GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Remove the throttle body air inlet duct. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L or Air Cleaner Assembly Replacement in Engine Controls - 3.8L.

  2. Object Number: 48166  Size: SH
  3. Depress the reverse servo cover (40).
  4. Remove the snap ring (39).

  5. Object Number: 48171  Size: SH
  6. Pull the O-ring seal (41) out through the slot in the case.
  7. Use side cutting pliers in order to cut the servo cover O-ring seal (41).
  8. Depress the reverse servo cover (40), grasp one end of the cut seal (41) and pull the seal (41) out of the servo cover (40).

  9. Object Number: 48173  Size: SH
  10. Remove the reverse servo cover (40).
  11. Remove the servo assembly (42-48).
  12. Remove the servo spring (49).

Installation Procedure

    Important: Follow this procedure exactly or the transaxle will have no reverse gear due to the servo pin missing the band.

  1. Jack up the driver side (channel plate side) of the car until the driver side is higher than the differential side. This ensures that the reverse band is in the proper location and not cocked to the channel plate side of the case.

  2. Object Number: 48173  Size: SH
  3. Install the servo spring (49).
  4. Install the servo assembly (42-48).
  5. Install the reverse servo cover (40) with new O-ring seal (41).
  6. Install the snap ring (39).
  7. Install the throttle body air inlet duct. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L or Air Cleaner Assembly Replacement in Engine Controls - 3.8L.
  8. Important: It is recommended that transmission adaptive pressure (TAP) information be reset.

    Resetting the TAP values using a scan tool will erase all learned values in all cells. As a result, The ECM, PCM or TCM will need to relearn TAP values. Transmission performance may be affected as new TAP values are learned.

  9. Reset the TAP values. Refer to Adapt Function .