Diagnostic Aids
Gear clash is a grinding noise that is made when shifting gears. You should perform a static shift and dynamic shift test. If the transmission develops gear clash, first check the clutch adjustment or faulty clutch condition. A clutch that drags or does not fully engage is the most common cause of gear clash. If the clutch is at fault , the clash should occur in every gear. If the clutch is all right, or the clash does not occur in all gears, check for worn or damaged synchronizers, including the sleeves, hubs and the blocking rings. Also check for loose mounting bolts or misalignment.
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
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This step checks for proper clutch operations.
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This step checks for air the hydraulic clutch system.
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This step checks for a worn pilot bearing.
Step | Action | Yes | No |
|---|---|---|---|
DEFINITION: The transmission gears clash when shifting from one gear into another gear. | |||
1 | Did you review the manual transmission symptoms and perform the necessary inspections? | Go to Step 2 | |
Inspect for proper clutch operation. Refer to Symptoms - Clutch in Clutch. Does the clutch operate properly? | Go to Step 7 | Go to Step 3 | |
3 | Verify that the clutch is releasing properly. Refer to Hydraulic Clutch Description in Clutch. Is the clutch releasing properly? | Go to Step 5 | Go to Step 4 |
4 | Repair the clutch system. Refer to Clutch Assembly Replacement in Clutch. Did you find and repair the condition? | Go to Step 16 | Go to Step 5 |
Test for air in the clutch hydraulic system. Is there air in the hydraulic system? | Go to Step 6 | Go to Step 7 | |
6 | Pump the clutch pedal 25 times. Do the gears still clash? | Go to Step 7 | Go to Step 16 |
7 | Inspect the transmission shift tower for wear. Is the transmission shift tower worn? | Go to Step 8 | Go to Step 9 |
8 | Replace the transmission shift tower. Refer to Shift Tower Replacement . Did you find and repair the condition? | Go to Step 16 | Go to Step 9 |
9 | Inspect the transmission fluid level. Refer to Fluid Replacement . Did you find and repair the condition? | Go to Step 16 | Go to Step 10 |
10 | Inspect for the correct type transmission fluid. Refer to Lubrication Specifications . Is the correct type transmission fluid being used? | Go to Step 12 | Go to Step 11 |
11 | Drain and refill the transmission. Refer to Fluid Replacement . Did you find and repair the condition? | System OK | Go to Step 12 |
Inspect the pilot bearing for binding. Is the pilot bearing binding? | Go to Step 13 | Go to Step 14 | |
13 | Replace the clutch pilot bearing. Refer to Clutch Pilot Bearing Replacement in Clutch. Did you find and repair the condition? | Go to Step 16 | Go to Step 14 |
14 | Disassemble and inspect the gear shift components and/or synchronizers for damage or wear. Refer to Transmission Disassemble . Are the gear shift and/or synchronizers worn or damaged? | Go to Step 15 | Go to Diagnostic Aids |
15 | Replace worn and/or damaged components as necessary. Did you find and repair the condition? | Go to Step 16 | Go to Diagnostic Aids |
16 | Operate the system and verify the repair. Did you correct the condition? | System OK | Go to Step 1 |
