GM Service Manual Online
For 1990-2009 cars only

Causes

Action

Loss of fluid in Clutch C4 or in the Fluid Circuit.

  1. Search for the leaking part.
  2. Replace the leaking part.

Incorrect fluid pressure.

Perform the Line Pressure Check .

Bridging the 4th gear Clutch (the 4th Gear Lockup Clutch) cannot be released.

Overhaul or replace the Transmission.