Initial Inspection and Diagnostic Overview

Before attempting to repair the clutch, manual transmission or related hydraulic components for any reason other than an obvious failure, the problem and probable cause should be identified. A large percentage of clutch and manual transmission problems show up as shifting difficulties, such as high shift effort, gear clash and grinding, or transmission blackout. When any of these conditions occur, a careful analysis of these difficulties should be performed before removing the clutch or manual transmission for repairs. Refer to "CLUTCH SYSTEM DIAGNOSIS" for conditions, causes and corrections.

Before removal of the clutch hydraulic system, verify the malfunction by removing the flywheel housing cover and measure the travel of the clutch actuator pushrod (6-speed only). With the clutch pedal pushed fully to the floor, the clutch actuator pushrod should extend a minimum of 11 mm (0.43 inch). Do not replace the hydraulic system if pushrod travel exceeds this distance.

If the clutch actuator pushrod does not meet the travel requirements, check the clutch master cylinder reservoir fluid level.
- The clutch actuator cylinder must be in place when checking the fluid level.
- The proper level is indicated by a step on the clutch master cylinder reservoir. Fill to specified level with hydraulic clutch fluid GM P/N 12345347 or equivalent.
- Do not overfill. The upper portion of the clutch master cylinder reservoir must accept fluid that is displaced from the clutch actuator cylinder as the clutch wears.

NOTICE: Carefully clean the top and sides of the clutch master cylinder reservoir before opening to prevent contamination of the system with dirt, water or other foreign material. Remove the clutch master cylinder reservoir diaphragm before adding fluid. Carefully replace the diaphragm, cover gasket and cover after filling.

If the clutch master cylinder reservoir requires any fluid, check the clutch hydraulic system components for leakage. Remove the rubber boots from the clutch master cylinder and check for leakage past the pistons. A slight wetting of the surfaces is acceptable. Replace the clutch hydraulic system if excessive leakage is evident.