GM Service Manual Online
For 1990-2009 cars only

Cause

Action

DEFINITION: The clutch does not disengage completely to allow smooth shift operations. It may cause gear clashing while the vehicle is not moving, at idle, and shifting out of neutral, or hard shifting in and out of gears while driving the vehicle.

Review the Symptoms - Clutch and perform the necessary inspections.

Pedal blocked from full travel

  1. Inspect for obstacles that will prevent the pedal from going to the floor.
  2. Clear any obstacles from under the pedal area, such as floor mats, damaged floor, or interior panels.

Too much travel between pedal and clutch master cylinder

  1. Inspect the pedal for worn bushings.
  2. Replace the pedal bushings if worn. Refer to Clutch Pedal Replacement .

Clutch pedal mounting loose

  1. Inspect the clutch pedal mounting bracket for loose or missing fasteners.
  2. Replace or repair the fasteners. Refer to Clutch Pedal Replacement .

Linkage at pedal worn or damaged

  1. Inspect the linkage at the pedal for excessive wear.
  2. Repair or replace the linkage as required. Refer to Clutch Pedal Replacement .

Clutch master cylinder seized or binding

  1. Inspect the master cylinder for the piston being able to move freely and full range of travel.
  2. Replace the clutch master cylinder as required. Refer to Clutch Master Cylinder Replacement .

Air in the clutch hydraulic system

Bleed the clutch hydraulic system. Refer to Hydraulic Clutch Bleeding .

Clutch actuator cylinder seized or binding

  1. Inspect the clutch actuator piston for moving freely.
  2. Replace the clutch actuator cylinder if the piston is binding. Refer to Clutch Actuator Cylinder Replacement .

Clutch master cylinder leaking internally

  1. Inspect for proper pedal reserve. Refer to Clutch System Description and Operation .
  2. 1.1. Let up halfway on pedal.
    1.2. Apply the pedal a few times and hold down for 30 seconds.
    1.3. Inspect to ensure there is still the proper pedal reserve, without letting pedal fully up.
  3. Replace the clutch master cylinder if it will not hold pedal reserve. Refer to Clutch Master Cylinder Replacement .

Damaged clutch assembly components

  1. Remove the clutch assembly.
  2. Inspect the following clutch assembly components for damage:
  3. • Damaged clutch disc hub splines
    • Bent clutch disc
    • Bent drive straps
    • Broken or warped pressure plate
  4. Replace the clutch assembly if any of the above damage is found. Refer to Clutch Assembly Replacement .

Excessive side loading on the release bearing

  1. Inspect the following clutch system components:
  2. • Worn or damaged pilot bearing
    • Excessive flywheel runout
    • Excessive engine to transmission misalignment
    • Clutch actuator cylinder mounting surface out of alignment
  3. Repair or replace any faulty components.

Faulty pilot bearing

Replace the pilot bearing. Refer to Clutch Pilot Bearing Replacement .

Transmission input shaft splines worn or damaged

Replace the transmission input shaft. Refer to Transmission Disassemble in Manual Transmission - NV 3500 Unit Repair or Transmission Disassemble in Manual Transmission - NV 4500 Unit Repair or Transmission Disassemble in Manual Transmission - ZF S6-650 Unit Repair.

Tight or contaminated clutch disc splines

  1. Clean the clutch disc and input shaft splines.
  2. If the clutch disc will not clean, replace the clutch assembly. Refer to Clutch Assembly Replacement .

Flywheel housing, engine block to clutch housing, or transmission front case excessively misaligned

  1. Inspect the clutch housing or the transmission front case for being faulty.
  2. Replace the clutch housing if it is faulty. Refer to Transmission Replacement in Manual Transmission - NV 4500.
  3. Replace the transmission front case half. Refer to Transmission Disassemble in Manual Transmission - NV 3500 Unit Repair or Transmission Disassemble in Manual Transmission - ZF S6-650 Unit Repair.

Grease or oil contamination on the clutch discs facing

  1. Repair the oil leak.
  2. Repair the grease leak.
  3. Clean the clutch disc facing and the other clutch assembly components.
  4. Replace the clutch assembly if it will not clean. Refer to Clutch Assembly Replacement .