VIBRATION/FLUID LEAK OUT OF CASE EXTENSION. Chevrolet Chevy Suburban

TRANSMISSION TYPE 4L80E 4L80E HD

REVISION 01/04/93

THIS BULLETIN HAS BEEN REVISED TO CORRECT THE PARTS INFORMATION.

SUBJECT: VIBRATION/FLUID LEAK OUT OF CASE EXTENSION (REPLACE CASE EXTENSION ASSEMBLY)

MODELS: 1993 CHEVROLET AND GMC C AND P TRUCKS AND G-VAN

TRANSMISSION MODELS: ABP, ADP, AFP, DCP, DSP, TXP, TWP, LAP, MHP, JDP, BAP, BSP, MAP, MBP, MCP, MJP, MLP

TRANSMISSION APPLICATIONS: 1993 HYDRA-MATIC 4L80-E/4L80-EHD (MT1)

CONDITION:

SOME HYDRA-MATIC 4L80-E/4L80-EHD TRANSMISSIONS MAY LEAK FLUID AT THE BACK OF THE CASE EXTENSION ASSEMBLY (19) OR A VIBRATION MAY BE NOTICED IN ALL RANGES AT ALL SPEEDS.

CAUSE:

THIS IS CAUSED BY THE EXTENSION BUSHING (77) NOT SEATED PROPERLY DUE TO AN OVERSIZED BORE, POSSIBLY INTERFERING WITH THE CASE EXTENSION HELIXSEAL ASSEMBLY (20).

CORRECTION: (FIGURE 2)

INSPECT THE CASE EXTENSION HELIXSEAL ASSEMBLY (20) FOR ANY DAMAGE AND SEE IF THE BUSHING (77) HAS MOVED. IF THE BUSHING HAS MOVED, ORDER A NEW CASE EXTENSION ASSEMBLY (19) WHICH INCLUDES THE PROPERLY INSTALLED BUSHING AND INSTALL A NEW HELIXSEAL ASSEMBLY (20).

DO NOT ATTEMPT TO REPAIR THE EXTENSION BY STAKING, SEALING, OR SECURING BUSHING IN PLACE.

SERVICE INFORMATION: (FIGURE 1)

STARTING JANUARY 14, 1993 (JULIAN DATE 014) ALL 1993 HYDRA-MATIC 4L80-E/4L80-EHD MODELS WILL HAVE THE CORRECTED CASE EXTENSION ASSEMBLY.

PARTS INFORMATION:

PART NUMBER PART DESCRIPTION

8677464 EXTENSION ASSEMBLY-CASE (19) 8681168 SEAL-EXTENSION TO CASE (15) 8675730 HELIXSEAL ASSEMBLY-CASE EXTENSION (20)

PARTS ARE CURRENTLY AVAILABLE AT GMSPO.

FIGURES: 2

Object Number: 81248 Size: FS

Object Number: 81925 Size: FS

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