GM Service Manual Online
For 1990-2009 cars only

Probable Cause

Action

DEFINITION: Gear disengagement occurs during normal operation.

The transmission shift control closeout boot is not positioned correctly.

  1. Inspect the transmission shift control closeout boot positioning.
  2. Reposition or replace the closeout boot, if necessary.

Refer to Shift Control Shift Closeout Boot Replacement .

The transmission shift linkage is out of adjustment.

Inspect the transmission shift linkage and adjust the shift linkage if necessary.

Refer to Shift Linkage Adjustment .

The transmission shift control is loose or damaged.

  1. Remove the transmission shift control.
  2. Inspect the transmission shift control and replace if necessary.

Refer to Shift Control Assembly Replacement .

The engine and/or the transaxle mounts are loose or damaged.

  1. Inspect the engine mounts.
  2. Tighten to specifications or replace as necessary.
  3. Refer to Crankshaft Balancer Replacement and Engine Mount Replacement - Right Side in Engine Mechanical.

  4. Inspect the transaxle mount.
  5. Tighten to specifications or replace as necessary.
  6. Refer to Transmission Mount Replacement in Rear Drive Axle.

The transmission has worn or damaged internal components.

  1. Remove the transmission.
  2. Refer to Transmission Replacement .

  3. Disassemble the transmission and inspect the following components for wear of damage:
  4. • Shift forks
    • Selector plates
    • Interlock plate
    • Selector arm
    • Shift rail
    • Springs
    • Gear Teeth
    • Synchronizers
    • Thrust washers and/or output shaft gear
    • (May be causing excessive end play.)

Refer to Transmission Disassemble the Transmission Unit Repair Manual.