GM Service Manual Online
For 1990-2009 cars only

Slips in Drive or No Drive

Condition

Action

DEFINITION: Slips in drive or no drive

Fluid Level Low and/or Contaminated or unit filled with the wrong type of fluid

Inspect fluid level and color. Perform a fluid level inspection and make sure that the fluid does not smell burnt, and shows no sign of coolant cross contamination. If unable to determine if the transmission has the correct type of fluid, drain the unit and refill with the correct fluid and retest.

Low System Line Pressure

Fluid

Low fluid level, perform fluid level check and correct as needed.

Fluid Pump (2)

Internal fluid pump (2) concern, diagnose fluid pump assembly and repair or replace assembly as necessary.

Torque Converter (1)

Internal concern, diagnose the cause of the concern and repair as necessary. Replace the torque converter assembly.

Fluid Filter (42)

Fluid filter (42) restricted. Diagnose the cause of the restriction and repair as necessary and replace the filter assembly.

Internal Transmission Concerns

Internal fluid leak, perform system air checks and repair as necessary.

External Control Valve Body Assembly (39)

Line Pressure Control Solenoid Valve Assembly (SLT) (316)

Verify that the line pressure control solenoid valve assembly (SLT) (316) responds electrically. If there is no response, perform an electrical diagnosis. If there are no electrical concerns, remove the solenoid valve assembly, inspect the O-ring seal, and bore for signs of damage and or missing seal. If the valve responded electrically and there are no bore or seal concerns, replace the line pressure control solenoid valve assembly due to possible internal mechanical concerns and retest. If a concern is still present after replacing the line pressure control solenoid valve (316), replace the control valve body assembly (39).

Internal Control Valve Body Assembly (39)

    • Primary Regulator Valve (395)
    • Check Valve (360)
    • Manual Valve (337)
    • Line Pressure Control (SLT) Accumulator Piston (433)

Remove the control valve body assembly to inspect the items listed. Inspect internal bores and valves for signs of wear and/or damage, including internal contamination. If unable to verify a repairable concern, replace the complete valve body assembly.

Clutch - Mechanical/Hydraulic

1-2 Reverse (B5) Clutch Assembly

Remove the transmission case cover and 1-2 reverse clutch assembly (B5) (19). Inspect all 1-2 reverse (B5) clutch components and operation. Repair as necessary.

Forward (C1) Clutch

Remove the transmission case cover and 1-2 reverse clutch assembly (B5) (19) and the forward and direct clutch assembly (23). Inspect all forward clutch (C1) components and operation. Repair as necessary.

Front Internal Gear and Low Clutch Sprag (F2) Assembly (25)

Remove the transmission case cover and 1-2 reverse clutch assembly (B5) (19), the forward and direct clutch assembly (23), the front carrier sun gear assembly (24), and the front internal gear and low clutch sprag assembly (25). Inspect all components and operation. Repair as necessary.