CLUTCH HYDRAULIC SYSTEM FLUID LEAKS. GMC Truck GMC Suburban

SUBJECT: CLUTCH HYDRAULIC SYSTEM FLUID LEAKS (INSTALL MASTER CYLINDER WITH REVISED SEAL)

MODELS: 1992-95 CHEVROLET AND GMC C/K MODELS WITH MANUAL TRANSMISSION

CONDITION:

SOME VEHICLES MAY EXHIBIT A CLUTCH HYDRAULIC SYSTEM FLUID LEAK. THE LEAK IS USUALLY FROM THE MASTER CYLINDER NEAR THE CLUTCH PUSH ROD.

CAUSE:

THE MASTER CYLINDER SEAL MAY LEAK UNDER HIGH PRESSURE AND MAY ALLOW THE PISTON TO CONTACT AND SCRATCH THE CYLINDER BORE.

CORRECTION:

INSTALL A MASTER CYLINDER WITH A REVISED SEAL. THE CLUTCH HYDRAULIC SYSTEM WILL NOW BE SERVICED WITH INDIVIDUAL COMPONENTS RATHER THAN A COMPLETE SYSTEM.

MASTER CYLINDER KIT, P/N 12385527, CONTAINS: - A DRY MASTER CYLINDER AND CAP - A PUSH ROD, A NEW ROLL PIN FOR ATTACHING TO THE HYDRAULIC LINE - A COTTER PIN TO BE PLACED THROUGH THE ROLL PIN - A NEW SEAL FOR THE HYDRAULIC LINE CONNECTION

CLUTCH ACTUATOR CYLINDER KIT, P/N 12387711, CONTAINS: - A DRY ACTUATOR CYLINDER - A NEW ROLL PIN FOR ATTACHING TO THE HYDRAULIC LINE - A COTTER PIN TO BE PLACED THROUGH THE ROLL PIN - A NEW SEAL FOR THE HYDRAULIC LINE CONNECTION

CLUTCH HYDRAULIC TUBE KIT, P/N 12387709, CONTAINS: - A CLUTCH HYDRAULIC TUBE - TWO NEW ROLL PINS FOR ATTACHING TO THE MASTER AND ACTUATOR CYLINDERS - TWO COTTER PINS TO BE PLACED THROUGH THE ROLL PINS - TWO NEW SEALS FOR THE MASTER AND ACTUATOR CYLINDER CONNECTIONS

REFER TO THE APPROPRIATE SERVICE MANUAL, SECTION 7C CLUTCH, FOR THE REPLACEMENT AND BLEEDING PROCEDURE.

IMPORTANT: WHEN REFILLING THE SYSTEM, USE ONLY DOT 3 BRAKE FLUID, P/N 1052535, FROM A SEALED CONTAINER. DO NOT USE MINERAL OR PARIFIN BASED OIL IN THE CLUTCH HYDRAULIC SYSTEM. THESE FLUIDS WILL DAMAGE THE RUBBER PARTS IN THE CYLINDERS.

PARTS INFORMATION

P/N DESCRIPTION 12385527 CLUTCH MASTER CYLINDER KIT 12387711 CLUTCH ACTUATOR CYLINDER KIT 12387709 CLUTCH TUBE KIT 1052535 FLUID, HYDRAULIC BRAKE

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION DESCRIPTION LABOR TIME K0600 CYLINDER, ACTUATOR USE PUBLISHED CLUTCH MASTER, LABOR OPERATION R+R OR REPLACE TIME

K0620 CYLINDER, CLUTCH USE PUBLISHED ACTUATOR, LABOR OPERATION R+R OR REPLACE TIME

K0040 CLUTCH SYSTEM, USE PUBLISHED HYDRAULIC-BLEED LABOR OPERATION TIME FIGURES: 0

CAPTIONS: 0

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER". THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS THAT MAY OCCUR ON SOME VEHICLES, OR TO PROVIDE INFORMATION THAT COULD ASSIST IN THE PROPER SERVICE OF A VEHICLE. PROPERLY TRAINED TECHNICIANS HAVE THE EQUIPMENT, TOOLS, SAFETY INSTRUCTIONS AND KNOW-HOW TO DO A JOB PROPERLY AND SAFELY. IF A CONDITION IS DESCRIBED, DO NOT ASSUME THAT THE BULLETIN APPLIES TO YOUR VEHICLE, OR THAT YOUR VEHICLE WILL HAVE THAT CONDITION. SEE A GENERAL MOTORS DEALER SERVICING YOUR BRAND OF GENERAL MOTORS VEHICLE FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.