Test Description

The numbers below refer to the step numbers on the diagnostic table. See Fig 1.

1. 2
   
   This step is to ensure the use of the proper transmission fluid. A special fluid is used to ensure proper synchronizer operation, and for sufficient lubrication. Improper fluid may cause the synchronizers to stick or the transmission components to overheat.
2. 4
   
   A static shift test is performed by shifting into all gears with the engine not operating. By confirming that the transmission can be shifted into all positions, ensures that the shift lever is not excessively worn or damaged.
3. 6
   
   A dynamic shift test is performed by shifting into all of the gear positions with the engine operating. Test to ensure that the internal shift components are functioning properly.
Fig 1: Transmission Locked in One Gear Diagnostic Table (Steps 1-9)
Courtesy of GENERAL MOTORS CORP.