GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2001 🢒 Sonoma Pickup - 2WD 🢒 Transmission/Transaxle 🢒 Clutch 🢒 Clutch Grabbing

Diagnostic Aids

When the clutch is disengaged and the vehicle lurches or shudders. In many instances it could be as minor as the engine mounts are loose or damaged. If this condition still exist, remove the transmission then you should check the pressure plate for burned or smeared resin from the clutch disc and for oil on the pressure plate. Check for worn or damaged release bearing and the splines on the transmission main drive gear.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

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

    2.

  2. This step inspects for faulty engine mounts

    3.

  3. This step inspects for fluid leakage on the clutch system components.

Step

Action

Yes

No

DEFINITION: The clutch grabs or chatters during engagement.

1

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

Go to Step 2

Go to Symptoms - Clutch

2

Inspect the engine mounting fasteners.

Are the engine mounts loose or tightened out of sequence?

Go to Step 3

Go to Step 4

3

Tighten the engine mounting fasteners to the specified torque. Refer to Fastener Tightening Specifications .

Does the clutch still grab?

Go to Step 4

System OK

4

Check for a damaged engine mount.

Is the engine mounting damaged?

Go to Step 5

Go to Step 6

5

Replace the engine mount. Refer to Engine Mount Replacement - Left Side and Engine Mount Replacement - Right Side in Engine Mechanical.

Does the clutch still grab?

Go to Step 5

System OK

6
  1. Remove the transmission. Refer to Transmission Replacement in Manual Transmission - NV1500.
  2. Inspect the pressure plate assembly for burned or smeared resin.

Is there burned or smeared resin on the pressure plate?

Go to Step 7

Go to Step 8

7
    • If there are burns or smears, clean or sand off the excess resin.
    • If the pressure plate assembly is burned or has heat checked parts, then replace the pressure plate assembly. Refer to Clutch Assembly Replacement .

Does the clutch still grab?

Go to Step 8

System OK

8

Inspect for a warped pressure plate.

Is the pressure plate warped?

Go to Step 9

Go to Step 10

9

Replace the pressure plate. Ensure that the runout does not exceed the amount given in the value column. Refer to Clutch Assembly Replacement .

Does the clutch still grab?

Go to Step 10

System OK

10

Inspect for oil on the clutch pressure plate facing or a burned or glazed facing.

Is there oil on the clutch pressure plate facing or a burned or glazed facing?

Go to Step 11

Go to Step 12

11

  1. Correct the leak at the source. Refer to Oil Leak Diagnosis in Engine Mechanical.
  2. Install a new clutch pressure plate.

Does the clutch still grab?

Go to Step 12

System OK

12

Inspect for worn splines on the transmission main drive gear.

Are there worn splines on the transmission main drive gear?

Go to Step 13

Go to Step 14

13

Inspect the release bearing at the transmission main drive gear.

Is the release bearing binding?

Go to Step 14

System OK

14

Replace the release bearing. Refer to Clutch Concentric Actuator Cylinder Replacement .

Did you find and repair the condition?

Go to Step 15

Go to Diagnostic Aids

15
  1. Install the transmission. Refer to Transmission Replacement in Manual Transmission - NV1500.
  2. Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 1