DEFINITION: A clunk is heard and/or felt on acceleration or deceleration.

Did you review the manual transmission symptoms and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Manual Transmission

Inspect the engine mounts for being loose or damaged. Refer to Engine Mount Inspection in Engine Mechanical - 6.6L or Engine Mount Inspection in Engine Mechanical - 8.1L.

Did you find and repair the condition?

Go to Step 7

Go to Step 3

Inspect the transmission mounts for being loose or damaged. Refer to Transmission Mount Replacement .

Did you find and repair the condition?

Go to Step 7

Go to Step 4

Notice: Refer to Fastener Notice in the Preface section.

Inspect the transmission to engine fasteners for being loose or missing. Refer to Fastener Tightening Specifications .

Did you find and repair the condition?

Go to Step 7

Go to Step 5

Inspect the driveline for causing the clunk. Refer to Propeller Shaft Diagnosis in Propeller Shaft.

Did you find and repair the condition?

Go to Step 7

Go to Step 6

1. Remove the transmission. Refer to Transmission Replacement .
2. Disassemble the transmission. Refer to Transmission Disassemble .
3. Inspect the following transmission components that may be causing the clunk:

•	The mainshaft bearing preload

•	The countershaft bearing preload

•	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 7

Go to Diagnostic Aids

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 1