INFO. ON HYDRA-MATIC 4T60-E TRANSAXLE PARTS USAGE

REVISION: 03/08/94

THIS BULLETIN IS BEING REVISED TO CHANGE THE MODELS AFFECTED, TEXT AND FIGURES 3 AND 9. PLEASE DISCARD BULLETIN 377132. ----------------------------------------------------------------------

SUBJECT: INFORMATION ON 4T60-E TRANSAXLE FOURTH CLUTCH AND HYDRAULIC UPDATES

MODELS: 1991 BUICK REATTA 1991-93 BUICK RIVIERA 1991-94 BUICK PARK AVENUE AND REGAL 1992-94 BUICK LE SABRE 1994 BUICK CENTURY AND SKYLARK 1991-93 CADILLAC ELDORADO, SEVILLE, SIXTY SPECIAL AND FLEETWOOD (FWD) 1991-94 CADILLAC DE VILLE 1991-94 CHEVROLET LUMINA 1992-94 CHEVROLET LUMINA APV 1994 CHEVROLET BERETTA AND CORSICA 1991-94 OLDSMOBILE NINETY EIGHT AND CUTLASS SUPREME 1992-94 OLDSMOBILE EIGHTY EIGHT AND SILHOUETTE 1991-92 OLDSMOBILE TORONADO AND TROFEO 1994 OLDSMOBILE CUTLASS CIERA AND ACHIEVA 1992-94 PONTIAC BONNEVILLE AND TRANS SPORT 1991-94 PONTIAC GRAND PRIX 1994 PONTIAC GRAND AM

TRANSAXLE APPLICATIONS: HYDRA-MATIC 4T60-E (RPO M13)

SEVERAL REVISIONS WERE IMPLEMENTED INTO ALL HYDRA-MATIC 4T60-E (RPO M13) TRANSAXLES AT THE START OF THE 1993 MODEL YEAR. THESE REVISIONS CONSIST OF MODIFICATIONS TO THE FOLLOWING COMPONENTS:

O CONTROL VALVE BODY, SPACER PLATE AND GASKETS O CHANNEL PLATE O FOURTH CLUTCH PLATES AND APPLY PISTON

1991-92 AND 1993-94 MODEL COMPONENTS LISTED ABOVE SHOULD NOT BE MIXED ON A TRANSAXLE DURING SERVICE. FOR EXAMPLE, USING A 1991-92 VALVE BODY GASKET ON A 1993-94 4T60-E TRANSAXLE (OR VICE VERSA) WILL CAUSE THE TRANSAXLE TO HAVE SOFT SHIFTS, SLIPPING AND WILL EVENTUALLY BURN CLUTCHES WITHIN A SHORT PERIOD OF TIME OR MILEAGE.

THESE CHANGES WERE DONE AS A "PACKAGE" AND UPDATES TO 1991-92 MODEL TRANSAXLES SHOULD NOT BE PERFORMED UNLESS ALL OF THE LISTED COMPONENTS ARE REPLACED. FAILURE TO COMPLY WILL RESULT IN PREMATURE TRANSAXLE FAILURES.

IMPORTANT: WHENEVER SERVICING A 4T60-E TRANSAXLE, COMPARE AND VERIFY THE COMPONENTS LISTED ABOVE THAT ARE REMOVED ARE IDENTICAL TO THE NEW REPLACEMENT COMPONENTS BEFORE REINSTALLING. SEE FIGURES 1 THROUGH 9 FOR COMPONENT REVISIONS BETWEEN 1991-92 AND 1993-94.

SERVICE PART INFORMATION:

+-----------------------------------------------------------------+ | 1991-92 | 1993-94 | | | PART NUMBER | PART NUMBER | DESCRIPTION | |-------------+-------------+-------------------------------------| | 8651901 | 8651929 | PACKAGE, OVERHAUL REPAIR COMPLETE | |-------------+-------------+-------------------------------------| | 8651900 | 8651928 | PACKAGE, OVERHAUL SEALS AND GASKETS | +-----------------------------------------------------------------+

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

FIGURES: 9

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