GM Service Manual Online
For 1990-2009 cars only

Diagnostic Aids

Inspect the clutch disc to be sure it is properly seated. Inspect for worn facings on the disc plate, and for the disc to be covered in fluid. Also inspect for a worn or a damaged clutch cover, and weak diaphragm springs.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step inspects the parts and the operation of the clutch system.

  2. This step inspects the source of the fluid leak.

  3. This step inspects for a worn facing, or for the facing torn from the disc plate.

Step

Action

Yes

No

DEFINITION: The clutch engages but slips while driving the vehicle.

1

Did you review the clutch symptom operations and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Clutch

2

Make 30-40 normal starts. Do not over-heat the clutch.

Does the clutch still slip?

Go to Step 3

System OK

3

  1. Remove the transmission. Refer to the following:
  2. •  Transmission Replacement in Manual Transmission - NV 3500
    •  Transmission Replacement in Manual Transmission - NV 4500.
    •  Transmission Replacement in Manual Transmission - ZF S6 650.
  3. Inspect the clutch disc.

Is the disc plate over heated?

Go to Step 4

Go to Step 5

4

Allow the disc plate to cool.

Does the clutch still slip?

Go to Step 5

System OK

5

Inspect the clutch disc in order to see if the disc is oil soaked.

Is the disc plate oil soaked?

Go to Step 6

Go to Step 7

6

  1. Repair the leak.
  2. Replace the clutch disc. Refer to Clutch Assembly Replacement .

Does the clutch still slip?

Go to Step 7

System OK

7

Inspect the clutch disc for a worn facing or if the facing is torn from the disc plate.

Is the facing worn or torn from the disc plate?

Go to Step 8

Go to Step 9

8

Replace the clutch disc. Refer to Clutch Assembly Replacement .

Does the clutch still slip?

Go to Step 9

System OK

9

Inspect for a weak diaphragm spring.

Is the diaphragm spring weak?

Go to Step 10

System OK

10

  1. Replace the disc plate. Refer to Clutch Assembly Replacement .
  2. Install the transmission. Refer to the following:
  3. •  Transmission Replacement in Manual Transmission - NV 3500.
    •  Transmission Replacement in Manual Transmission - NV 4500.
    •  Transmission Replacement in Manual Transmission - ZF S6-650.
  4. Operate the system in order to verify the repair.

Did you and repair the condition?

System OK

Go to Diagnostic Aids

11

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 1