A/T - Torque Converter Clutch Shutter
File In Section: 7 - TransmissionBulletin No.: 37-71-10
Date: September, 1994
Subject:
Torque Converter Clutch Shudder (New Converter Assembly)
Models:
1991-1994 Chevrolet and GMC Truck C/K, R/V, P Models, G Vans
Transmission Applications:
1991-1994 Hydra-Matic 4L8O-E/4L80-EHD
This bulletin is being revised to add the 1994 model year, enhance condition description and update the parts Information for the 6.5L engine. Previous divisional publication numbers were:
Chevrolet 93-114-7A
GMC Truck 93-7A-48
GM of Canada 93-7A-148
Condition
Some HYDRA-MATIC 4L80-E/4L80-EHD Transmissions may experience a Torque Converter Clutch (TCC) shudder concern during apply and/or release. Torque converter clutch shudder is a condition that exists only when the TCC is locking or unlocking. TCC shudder will usually be described as a shudder or vibration condition which can be felt in the truck during TCC lock or unlock.
Correction Replace the converter assembly with the New Converter Assembly.
Date Of Production The new Converter Assembly entered production January 11, 1993 (Julian Date 011) for 1993 HYDRA-MATIC 4L8O-E/4LBO-EHD models. On January 3, 1994 (Julian Date 003) the 1994 HYDRA-MATIC 4LBO-E/4L8O-EHD models for 6.5L diesel engines (L65/L56/L57) began using the same torque converter assembly as the 7.4L engine application.
Parts Information:
Parts are currently available from GMSPO.
Warranty Information:
For vehicles repaired under warranty, use:
Labor Operation Labor Time
K7020 Use published labor
operation time.