GM Service Manual Online
For 1990-2009 cars only

Condition

Action

Aerated fluid - incorrect fluid level

    • Adjust fluid to the proper level. Refer to Transmission Fluid Check .
    • Inspect for a defective pump.

Air flow to cooler obstructed

Remove the air flow obstruction.

Engine overheat

Correct the overheating condition. Refer to Symptoms - Engine Cooling in Engine Cooling.

Inaccurate temperature gauge or sending unit

Replace the gauge and/or sending unit.

Inaccurate sump temperature sensor

Replace the pressure switch manifold (PSM) or internal harness. Refer to Pressure Switch Manifold Replacement or Wiring Harness Replacement .

Excessive cooler circuit pressure drop

Inspect for plugged cooler, lines too small, collapsed hose, too many elbows in circuit.

Transmission cooler lines reversed

Connect the cooler lines properly. Oil and water should flow in opposite directions.

Fluid cooler lines restricted

Remove restrictions and clean or replace the lines. Refer to Transmission Fluid Cooler Hose/Pipe Replacement .

Torque converter - wrong converter, no torque converter clutch, stuck stator, or slipping stator

Replace or repair the converter assembly. Refer to Torque Converter Replacement .

A stuck stator will not allow cool down in Neutral.

Cooler flow loss due to internal transmission leakage

Overhaul the transmission.