GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2007 🢒 Lucerne 🢒 Transmission/Transaxle 🢒 Automatic Transaxle - 4T65-E 🢒 Accumulator and 2-1 Manual Servo Replacement

Removal Procedure
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  2. Remove the oil filter. Refer to Automatic Transmission Fluid and Filter Replacement .

    3. Object Number: 97335 Size: SH
  3. Remove the accumulator attaching bolts.

    4. Object Number: 97336 Size: SH
  4. Remove the 2-1 manual servo piston cover bolts.

    5. Object Number: 769139 Size: SH
  5. Use a large screwdriver in order to gently pry the lube oil pipe retainer from the case.
  6. Remove the lube oil pipe from the front differential carrier internal gear lube hole.

    7. Object Number: 97365 Size: SH
  7. Remove the accumulator assembly.

    8. Object Number: 97366 Size: SH
  8. Remove the 2-1 manual servo piston assembly and the filter.
  9. Remove the seal.
  10. Disassemble and inspect the accumulator and the 2-1 manual servo assemblies for foreign debris and clean as necessary.

Installation Procedure

    Object Number: 97366 Size: SH

    Important: The seal must be installed as shown. If it is not installed, or is installed in the wrong location, the transmission will operate only in reverse.

  1. Install the 2-1 manual servo piston assembly seal. Lubricate the seal with automatic transmission fluid.
  2. Install the 2-1 manual servo piston assembly and the filter. Make sure that the servo pin engages the band assembly.

    3. Object Number: 97365 Size: SH
  3. Install the accumulator assembly.

    4. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 97336 Size: SH
  4. Install the 2-1 manual servo piston cover bolts.

    5. Tighten
    Tighten the 2-1 manual servo piston cover bolts to 25 N·m (18 lb ft).


    Object Number: 769139 Size: SH
  5. Use a screwdriver in order to lock the lube oil pipe retainer into the case.

    6. Object Number: 97335 Size: SH
  6. Install the accumulator assembly attaching bolts.

    7. Tighten
    Tighten the accumulator bolts and the 2-1 manual servo bolts to 12 N·m (106 lb in).

  7. Install the new oil filter seal. Refer to Automatic Transmission Fluid and Filter Replacement .
  8. Lower the vehicle.
  9. Fill the transaxle to the proper level. Refer to Fluid Capacity Specifications .
  10. Inspect the transaxle fluid level. Refer to Transmission Fluid Check .
  11. Inspect the oil pan gasket for leaks.

    12. 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.

  12. Reset the TAP values. Refer to Transmission Adaptive Functions .