Diagnostic Aids
If the transmission jumps out of gear during deceleration, inspect the components that may allow for the gears or shafts to tip. If the gears or shafts tip, the synchronizer sleeve can disengage from the selector teeth on the speed gear. If the transmission jumps out of gear during acceleration, inspect the components that may not allow full engagement of the synchronizer sleeve to the selector teeth on the speed gear. Insufficient engagement of the selector teeth under torque may cause the transmission to jump out of gear.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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A static shift test is performed by shifting into all gear positions with the engine not operating. While performing the test, slowly move the shift lever. Feel for proper movement of the shift lever and transmission internal shift components.
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A dynamic shift test is performed by shifting into all gear positions with the engine operating. Test for the correct mesh of the synchronizers sleeve and the speed gear selector teeth. Move the shift lever to NEUTRAL and then let up on the clutch pedal. Depress the clutch pedal and move the shift lever to re-engage the gear, to ensure full travel of the shift components.
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This step inspects for worn or damaged transmission or engine mounts. Loose mounts may cause a shock on the transmission allowing for gear disengagement.
Step | Action | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
DEFINITION: Gear disengagement occurs during acceleration or deceleration. | |||||||||||
1 | Did you review the Symptoms - Manual Transmission, and perform the necessary inspections? | Go to Step 2 | |||||||||
Did the transmission shift completely into all gears? | Go to Step 4 | Go to Step 3 | |||||||||
3 | Remove the shifter and inspect for worn or faulty components. Refer to Transmission Control Replacement. Did you find and repair the condition? | Go to Step 8 | Go to Step 4 | ||||||||
Did the transmission shift completely into all gears? | Go to Step 5 | Go to Step 7 | |||||||||
Inspect the engine and/or transmission mounts. Refer to Transmission Mount Replacement. Did you find and repair the condition? | Go to Step 8 | Go to Step 6 | |||||||||
6 |
Did you find and repair the condition? | Go to Step 8 | Go to Step 7 | ||||||||
7 | Replace the transmission. Refer to Transmission Replacement. Is the replacement complete? | Go to Step 8 | -- | ||||||||
8 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 1 | ||||||||
