GM Service Manual Online
For 1990-2009 cars only

Caution: The antifreeze or water will deteriorate the seals, gaskets and the glue that bonds the clutch material to the pressure plate. Both conditions may cause permanent damage to the transmission.

If antifreeze or water has entered the transmission, perform the following:

  1. Disassemble the transmission.
  2. Replace all of the rubber type seals. The coolant will erode the seal material which will cause leakage.
  3. Replace the clutch plate assemblies with compound surface. The surface material may separate from the center part of the steel.
  4. Replace all of the nylon parts - washers.
  5. Replace the torque converter.
  6. Thoroughly clean and rebuild the transmission, using new gaskets and oil filter.
  7. Flush the cooler lines after the transmission cooler has been properly repaired or replaced.