INFORMATION ON TRANSAXLE PRODUCT UPDATES

SUBJECT: INFORMATION ON TRANSAXLE PRODUCT UPDATES

MODELS: 1995 BUICK CENTURY, PARK AVENUE, RIVIERA, LE SABRE, SKYLARK, REGAL 1995 CADILLAC DE VILLE 1995 CHEVROLET BERETTA, CORSICA, LUMINA, MONTE CARLO, CARLO AND LUMINA APV 1995 OLDSMOBILE CUTLASS CIERA, NINETY EIGHT, EIGHTY EIGHT, ACHIEVA, CUTLASS SUPREME, SILHOUETTE 1995 PONTIAC BONNEVILLE, GRAND AM, GRAND PRIX, TRANS SPORT WITH HYDRA-MATIC 4T60-E TRANSAXLE (RPO M13)

THE FOLLOWING PRODUCT UPDATES HAVE BEEN IMPLEMENTED ON THE HYDRA-MATIC 4T60-E TRANSAXLE DURING THE 1995 MODEL YEAR AND HAVE AN EFFECT ON SERVICE:

UPDATE DESCRIPTION: (FIGURE 2) THE INPUT CLUTCH FIBER AND STEEL PLATES WERE REVISED TO COMMONIZE USAGE WITH THE HYDRA-MATIC 3T40 TRANSAXLE. THE REVISED FIBER PLATES ARE THINNER AND THE REVISED STEEL PLATES ARE THICKER.

UPDATE IDENTIFICATION: (FIGURE 1 AND 2) THIS PRODUCT UPDATE WAS IMPLEMENTED IN PRODUCTION ON ALL 1995 4T60-E MODELS ON AUGUST 22, 1994 (JULIAN DATE 234). VISUAL IDENTIFICATION MAY BE DIFFICULT DUE TO THE SMALL DIMENSIONAL CHANGES. UNKNOWN FIBER AND STEEL INPUT CLUTCH PLATES CAN BE VERIFIED BY MEASURING THEIR THICKNESS.

EFFECT ON SERVICE: THE REVISED INPUT CLUTCH PACK CAN SERVICE ALL 1991-1995 4T60-E TRANSAXLES AND LATE 1990 (JANUARY 16, 1990, JULIAN DATE 016 AND LATER) AND 1991-1993 4T60 TRANSAXLES. WHEN SERVICING TRANSAXLES CONTAINING THE PREVIOUS DESIGN INPUT CLUTCH PACK, DO NOT MIX UP PREVIOUS AND NEW DESIGN PLATES AS THIS WILL RESULT IN EITHER A NO-BUILD OR DURABILITY CONCERN.

PARTS INFORMATION:

PREVIOUS NEW PART DESCRIPTION PART NUMBER NUMBER ---------------------------------------------------------------------- 8662850 SEE 24203185 PLATE ASSEMBLY, INPUT CLUTCH (FIBER) 8651446 SEE 24203185 PLATE, INPUT CLUTCH (STEEL) N/A 24203185 PACKAGE, INPUT CLUTCH PLATE (FIBER AND STEEL)

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

UPDATE DESCRIPTION: (FIGURE 3) THE CHANNEL PLATE ASSEMBLY AND SPACER PLATE WERE UPDATED DUE TO A REVISED LOW BLOW-OFF DESIGN.

UPDATE IDENTIFICATION: (FIGURE 1 AND 3) THIS PRODUCT UPDATE WAS IMPLEMENTED IN PRODUCTION ON ALL 1995 4T60-E MODELS ON OCTOBER 3, 1994 (JULIAN DATE 276). REFER TO FIGURE 3 FOR IDENTIFICATION OF THE LOW BLOW-OFF DESIGN CHANGES. THE SPACER PLATE CHANGE IS NOT READILY APPARENT. THE BEST WAY TO IDENTIFY THE SPACER PLATE IS TO DETERMINE WHICH CHANNEL PLATE WAS USED WITH IT. REPLACE THE SPACER PLATE IF THERE IS ANY QUESTION AS TO WHETHER IT IS THE PREVIOUS OR NEW DESIGN.

EFFECT ON SERVICE: THE REVISED CHANNEL PLATE AND SPACER PLATE ASSEMBLIES CAN SERVICE 1995 4T60-E TRANSAXLES ONLY. MIXING PREVIOUS AND NEW DESIGN CHANNEL PLATES AND SPACER PLATES MAY RESULT IN A TRANSAXLE DURABILITY OR PERFORMANCE CONCERN.

PARTS INFORMATION:

REFER TO THE SERVICE PARTS CATALOG FOR FIRST AND SECOND DESIGN CHANNEL PLATE AND SPACER PLATE ASSEMBLY PART NUMBERS BY TRANSAXLE MODEL.

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

UPDATE DESCRIPTION: (FIGURE 4) THE DRIVE LINK ASSEMBLY WAS REVISED TO AN "ELASTICALLY TUNED" ROCKER JOINT DESIGN. THE "ELASTICALLY TUNED" ROCKER JOINT DRIVE LINK ASSEMBLY HAS IMPROVED HIGH MILEAGE DURABILITY. 1995 BUICK RIVIERA MODELS USE A "SPECIAL" ROCKER JOINT DRIVE LINK SPECIFICALLY DESIGNED TO REDUCE NOISE ON THOSE MODELS.

UPDATE IDENTIFICATION: (FIGURE 1 AND 4) THIS PRODUCT UPDATE WAS IMPLEMENTED IN PRODUCTION ON HIGH TORQUE 1995 4T60-E MODELS (5ATW, 5YDW AND 5YNW) ON OCTOBER 3, 1994 (JULIAN DATE 276). THE REMAINING MODELS WILL PHASE INTO PRODUCTION BY THE END OF THE MODEL YEAR (EXCEPT 5BFW AND 5CAW BUICK RIVIERA MODELS). THE "ELASTICALLY TUNED" ROCKER JOINT DRIVE LINK ASSEMBLY CAN BE IDENTIFIED BY THE SHAPE OF THE OUTER LINK.

EFFECT ON SERVICE: THE "ELASTICALLY TUNED" ROCKER JOINT DRIVE LINK ASSEMBLY CAN SERVICE ANY 1993-1995 4T60-E TRANSAXLE (EXCEPT 5BFW AND 5CAW BUICK RIVIERA MODELS) EQUIPPED WITH A ROCKER JOINT DRIVE LINK ASSEMBLY. ON 1991- 1993 4T60-E TRANSAXLES EQUIPPED WITH ROUND PIN DRIVE LINK ASSEMBLIES, THE DRIVE AND DRIVEN SPROCKETS MUST BE UPDATED IN ORDER TO USE THE "ELASTICALLY TUNED" DRIVE LINK ASSEMBLY. REFER TO GM POWERTRAIN BULLETIN 9474T60-E-04A (CORPORATE BULLETIN 377107R) FOR INFORMATION ON ROCKER JOINT DRIVE LINK IMPLEMENTATION AND IDENTIFICATION.

PARTS INFORMATION:

PREVIOUS NEW PART PART NUMBER NUMBER DESCRIPTION ---------------------------------------------------------------------- 8682603 24202447 LINK ASSEMBLY, DRIVE (ALL EXCEPT 5BFW AND 5CAW) N/A 24200771 LINK ASSEMBLY, DRIVE (5BFW AND 5CAW - 1995 BUICK RIVIERA)

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

FIGURES: 4 ATTACHMENTS: 0

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COPYRIGHT 1995. GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.