Torque Converter - Squeak Noise

Number: 93-114A-7A
Section: 7A
Date: MARCH 1993
Corporate Bulletin No.: 377111R
ASE No.: A2

Subject:
TORQUE CONVERTER SQUEAKS

Model and Year:
1991-93 C/K, R/V AND P TRUCKS, G VAN
WITH 4L80-E/4L80-EHD AUTOMATIC TRANSMISSION

THIS BULLETIN CANCELS AND SUPERSEDES DEALER SERVICE BULLETIN NO. 93-114-7A, DATED FEB. 1993. THE YEAR HAS BEEN CORRECTED UNDER SERVICE PARTS INFORMATION. ALL COPIES OF 93-114-7A SHOULD BE DISCARDED.

CONDITION:

Some HYDRA-MATIC 4L80-E/4L80-EHD Transmissions may exhibit a torque converter squeak noise. The noise is noticeable at idle in park, neutral and park/neutral at engine shut-off or during coastdown, with a light load. The noise goes away when the vehicle is in drive or reverse at idle with the brakes applied.

CAUSE:

High spring load in the stator assembly of torque converter.

CORRECTION:

New converter assembly with a lower spring load in the stator assembly will significantly reduce any noise.





DATE OF PRODUCTION: (Figure 1)

Starting January 11, 1993 (Julian Date 011) all 1993 HYDRA-MATIC 4L80-E/4L80-EHD models will have the new converter assembly.








SERVICE PARTS INFORMATION:

Parts are currently available through GMSPO.