GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1997 🢒 Century 🢒 Transmission/Transaxle 🢒 Automatic Transaxle - 4T65-E 🢒 Reverse Servo Replacement

Removal Procedure
  1. Remove the air cleaner duct. Refer to Engine Controls.
  2. Remove the exhaust crossover pipe. Refer to Engine Exhaust.
  3. Remove the right (rear) exhaust manifold. Refer to Engine Mechanical.

    4. Object Number: 48166 Size: SH
  4. Depress the reverse servo cover.
  5. Remove the snap ring.

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

    9. Object Number: 48173 Size: SH
  9. Remove the reverse servo cover.
  10. Remove the servo piston.
  11. Remove the sealing ring.
  12. Remove the apply pin.
  13. Remove the servo spring.

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 it 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
  2. Install the servo spring.
  3. Install the apply pin.
  4. Install the sealing ring.
  5. Install the servo piston.
  6. Install the reverse servo cover.
  7. Install the snap ring.
  8. Install the right (rear) exhaust manifold. Refer to Engine Mechanical.
  9. Install the exhaust crossover pipe. Refer to Engine Exhaust.
  10. Install the air cleaner duct. Refer to Engine Controls.