MANUAL TRANSMISSION DISENGAGEMENT (REPL. BOOT)

SUBJECT: MANUAL TRANSMISSION DISENGAGEMENT (REPLACE SHIFT LEVER BOOT)

MODELS: 1990-94 CHEVROLET AND GMC C5H, C6H, C7H, B7 AND P6 MEDIUM DUTY MODELS WITH MANUAL TRANSMISSIONS

CONDITION:

SOME OWNERS MAY COMMENT THAT THEIR MANUAL TRANSMISSION JUMPS OUT OF GEAR. THIS CONDITION USUALLY OCCURS IN HIGHER GEARS, HOWEVER, IT MAY OCCUR IN ALL GEARS.

CAUSE:

GEAR DISENGAGEMENT MAY RESULT FROM THE INNER SHIFT BOOT BINDING BETWEEN THE FLOOR PANEL AND THE SHIFT TOWER. SECTION 7B OF THE APPROPRIATE MEDIUM DUTY SERVICE MANUAL PROVIDES OTHER CAUSES FOR "WALKING OR JUMPING OUT OF GEAR."

CORRECTION:

IF IT IS DETERMINED THAT THE SHIFT BOOT CAUSES GEAR DISENGAGEMENT, REPLACE THE SHIFT BOOT BY THE FOLLOWING PROCEDURE. THE NEW TRANSMISSION SHIFT BOOT ASSEMBLY HAS LARGER HOLE SIZES THAT HELP PREVENT THE BOOT FROM BINDING BETWEEN THE FLOOR PANEL AND THE SHIFT TOWER.

SERVICE PROCEDURE:

IMPORTANT: DO NOT OVERHAUL OR REPLACE THE TRANSMISSION TO CORRECT GEAR DISENGAGEMENT CONCERNS WITHOUT FIRST FOLLOWING THE PROCEDURES IN THIS BULLETIN.

1.BLOCK THE VEHICLE WHEELS AND APPLY THE PARKING BRAKE. 2.SHIFT THE TRANSMISSION INTO NEUTRAL. 3.REFERRING TO FIGURE 1, REMOVE THE FOUR SCREWS (1) FROM THE RETAINER (2) THAT ATTACHES THE SHIFT BOOT ASSEMBLY (3) TO THE FLOOR PANEL (4). SET THE SCREWS ASIDE. 4.REMOVE THE FOUR SCREWS (1) THAT ATTACH THE SHIFT BOOT ASSEMBLY (3) TO THE FLOOR PANEL (4). 5.REMOVE THE RETAINER (2) AND SHIFT BOOT ASSEMBLY (3) FROM THE SHIFT LEVER (5). 6.INSTALL NEW SHIFT BOOT (3) AND LOWER THE BOOT AND THE RETAINER (2) TO THE FLOOR PANEL. REFER TO SERVICE PARTS INFORMATION SECTION BELOW FOR THE CORRECT BOOT PART NUMBER. 7.REINSTALL THE FOUR SCREWS (1) INTO THE SHIFT BOOT ASSEMBLY (3). 8.REINSTALL THE FOUR SCREWS (1) INTO THE RETAINER (2) THAT ATTACHES THE SHIFT BOOT ASSEMBLY TO THE FLOOR PANEL. 9.TEST DRIVE TRUCK. 10.IF THE ABOVE PROCEDURE DOES NOT CORRECT GEAR DISENGAGEMENT OR IF THIS PROCEDURE IS NOT THE RESULT OF THE SHIFT BOOT, REFER TO SECTION 7B IN THE APPROPRIATE MEDIUM DUTY SERVICE MANUAL.

SERVICE PARTS INFORMATION

P/N DESCRIPTION QTY

15984021 SHIFT BOOT USED WITH 1 SINGLE SPEED REAR AXLES

15984022 SHIFT BOOT USED WITH 1 TWO SPEED REAR AXLES

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OP DESCRIPTION LABOR TIME K1080 SEAL AND/OR BOOT, USE PUBLISHED FLOOR MOUNTED LABOR OPERATION GEARSHIFT-REPLACE TIME

FIGURES: 1

CAPTIONS: FIGURE 1 - SHIFT BOOT ASSEMBLY

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.

COPYRIGHT 1994 GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.