LOSS OF DRIVE IN ALL RANGES (REPLACE CARRIER PACKAGE)

REVISION: 03/09/94

THIS BULLETIN IS BEING REVISED TO ADD THE IMPORTANT STATEMENT IN THE "CORRECTION" PART OF THE BULLETIN. ----------------------------------------------------------------------

SUBJECT: LOSS OF DRIVE IN ALL RANGES (REPLACE CARRIER PACKAGE)

MODELS: 1991-93 CHEVROLET AND GMC C/K, R/V, P TRUCKS AND G-VAN, JAGUAR, ROLLS-ROYCE

TRANSMISSION APPLICATIONS:

1991-1993 HYDRA-MATIC 4L80-E/ 4L80-EHD (MT1)

(REFER TO CORPORATE BULLETIN #377114R FOR THE 1991 AND 1992 SRTA SERVICE POLICIES AND PROCEDURES.)

CONDITION:

LOSS OF DRIVE IN ALL RANGES.

CAUSE:

THE TURBINE SHAFT MAY FRACTURE AT THE FORWARD CLUTCH FEED HOLE DUE TO HIGH MILEAGE AND/OR EXTREME SERVICE APPLICATIONS. IN 15,000 GVW AND HIGHER APPLICATIONS WITH A THREE PIECE PROP SHAFT SYSTEM, DRIVELINE ANGLE MISALIGNMENT MAY CAUSE A VIBRATION THAT CAN AFFECT THE TURBINE SHAFT. THIS MAY ALSO CAUSE A TRANSMISSION PUMP FAILURE.

CORRECTION:

BEGINNING ON MAY 5, 1993, (JULIAN DATE 125), THE TURBINE SHAFT MANUFACTURING PROCESS WAS CHANGED. THE CHANGES INCLUDED SHOT PEENING THE AREA AROUND THE FORWARD CLUTCH FEED HOLE, THE FEED HOLE DIAMETER REDUCED AND DRILLED THROUGH, THE TURBINE SHAFT GROOVE RADIUS INCREASED, AND A CHAMFER ADDED TO THE OVERDRIVE CARRIER.

IMPORTANT: GMC TRUCK DEALERS SHOULD REFER TO BULLETIN #367106, DATED DECEMBER 1993, AUTOMATIC TRANSMISSION SERVICE PROCEDURE CHANGES FOR IN WARRANTY REPAIRS. OUT OF WARRANTY REPAIRS MAY UTILIZE THIS BULLETIN.

SERVICE PARTS INFORMATION: JAGUAR/ROLLS-ROYCE APPLICATIONS: _______________________________ 24200350 CARRIER PACKAGE--OVERDRIVE CARRIER ASSEMBLY COMPLETE RING SEALS TURBINE SHAFT AND BALL ASSEMBLY TURBINE SHAFT FRONT OIL SEAL

ALL OTHER APPLICATIONS: ______________________ 24200130 CARRIER PACKAGE--OVERDRIVE CARRIER ASSEMBLY COMPLETE RING SEALS TURBINE SHAFT AND BALL ASSEMBLY TURBINE SHAFT FRONT OIL SEAL

FIGURES: 3

SERVICE PARTS ARE AVAILABLE THROUGH GMSPO.

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER." THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS OCCURRING 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 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 1993. GM POWERTRAIN DIVISION. GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.