For 1990-2009 cars

### Diagnostic Aids

All manual transmissions have gear play that might cause a clunk. If the transmission is suspected of causing the clunk, compare it with a similar vehicle. An internal clunk in the transmission is usually caused by wear between two components, or from improper assembly, which would also cause other symptoms.

### Test Description

The number below refers to the step number on the diagnostic table.

1. This step inspects the driveline component for causing the clunk. A faulty driveline component may resonate the clunk to the transmission, giving an indication that the transmission is causing the clunk.

Step | Action | Yes | No
--- | --- | --- | ---
DEFINITION: A clunk is heard and/or felt on acceleration or deceleration. If the transmission is equipped with an air shift control, refer to the transmission manufacturer repair manual for the correct diagnosis and repair.
1 | Did you review the manual transmission symptoms and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Manual Transmission
2 | Inspect the engine/transmission mounts for being loose or damaged. Refer to Engine Mount Inspection in Engine Mechanical - 8.1L or Engine Mount Inspection in 7.2L Catapillar or Transmission Mount/Support Replacement . Did you find and repair the condition? | Go to Step 8 | Go to Step 3
3 | Inspect the transmission to engine fasteners for being loose or missing. Refer to Clutch Assembly Replacement in Clutch. Did you find and repair the condition? | Go to Step 8 | Go to Step 4
4 | Inspect the driveline for causing the clunk. Refer to Ping, Snap, or Click Noise in Propeller Shaft. Did you find and repair the condition? | Go to Step 8 | Go to Step 5
5 | Inspect for loose propeller shaft yoke. Is the propeller shaft yoke loose? | Go to Step 6 | Go to Step 7
6 | Replace the propeller shaft yoke, washer, and nut. Refer to the transmission manufacturer repair manual. Did you find and repair the condition? | Go to Step 8 | Go to Step 7
7 |

1. Remove the transmission. Refer to Transmission Replacement .
2. Disassemble the transmission.

Refer to the transmission manufacturer repair manual.

3. Inspect the following transmission components that maybe causing the clunk:

• | The mainshaft bearing end play

• | The countershaft bearing end play

• | Worn speed gear teeth

• | Worn countershaft gear teeth

• | Worn synchronizer sleeve to hub

• | Worn thrust washers and thrust surfaces on the speed gears or mainshaft

Did you find and repair the condition?

Go to Step 8

Go to Diagnostic Aids

8 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 1