INFO. ON NEW LONG LIP SEAL DESIGN 3-4 & FORWARD CLUTCHES. GMC Truck GMC K Pickup

SUBJECT: INFORMATION ON NEW LONG LIP SEAL DESIGN 3-4 AND FORWARD CLUTCHES

MODELS: 1994 BUICK ROADMASTER 1994 CADILLAC FLEETWOOD 1994 CHEVROLET CAPRICE, CAMARO, CORVETTE 1994 PONTIAC FIREBIRD

1994 CHEVROLET AND GMC C/K, S/T TRUCKS AND M/L, G VANS 1994 OLDSMOBILE BRAVADA

TRANSMISSION APPLICATIONS: 1994 HYDRA-MATIC 4L60-E (RP0 M30)

BULLETIN COVERS: (FIGURE 1) NEW PRODUCT INFORMATION FOR 1994 HYDRA-MATIC 4L60-E TRANSMISSIONS. NEW CLUTCH PISTON SEAL DESIGN. THE 3-4 CLUTCH PISTON OUTER SEAL AND THE FORWARD CLUTCH PISTON OUTER SEALS HAVE BEEN REDESIGNED TO INCLUDE A LONG LIP PROFILE FOR ENHANCED SEALING. BE CERTAIN TO FAMILIARIZE YOURSELF WITH THESE UPDATES TO PROPERLY REPAIR THE 1994 HYDRA-MATIC 4L60-E TRANSMISSION.

DATE OF PRODUCTION CHANGE: (FIGURE 2) BEGINNING WITH AUGUST 09, 1993, THE HYDRA-MATIC 4L60-E TRANSMISSIONS WERE BUILT WITH A NEW 3-4 CLUTCH OUTER SEAL (LONG LIP). ON SEPTEMBER 20, 1993 THE HYDRA-MATIC 4L60-E TRANSMISSIONS WERE BUILT WITH A NEW FORWARD CLUTCH OUTER SEAL (LONG LIP).

SERVICE PARTS INFORMATION: THE NEW 3-4 CLUTCH OUTER SEAL AND FORWARD CLUTCH OUTER SEAL SHOULD BE USED WHEN REBUILDING TRANSMISSIONS THAT OPERATE UNDER -25 DEGREES F OR IF THE 3-4 CLUTCH PLATES OR FORWARD CLUTCH PLATES EXHIBIT A BURNT CONDITION.

THE LONG LIP SEALS ARE INTERCHANGEABLE WITH THE CURRENT SEALS. THE NEW DESIGN WILL REPLACE THE CURRENT SEAL IN SERVICE PACKAGES AS STOCK IS DEPLETED. TO ORDER THE LONG LIP SEALS INDIVIDUALLY USE THE FOLLOWING PART NUMBERS:

PART NUMBER PART NAME ___________ _________ 8642138 3-4 CLUTCH OUTER SEAL 8686146 FORWARD CLUTCH OUTER SEAL

THESE SEALS CAN ALSO BE USED FOR 1982-1993 HYDRA-MATIC 4L60 AND 4L60-E TRANSMISSIONS.

NOTE: THE GMC BULLETIN NO. 367106 AUTOMATIC TRANSMISSION SERVICE PROCEDURE, WILL REMAIN IN EFFECT FOR GMC TRUCKS ONLY.

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

FIGURES: 2

Object Number: 83023 Size: FS

Object Number: 84904 Size: FS

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.