A/T - Clutch Plate, Input Shaft, TCC Valve Revised
Number: 86-191Section: 7A
Date: NOV., 1986
Subject: THM 440T4 TRANSMISSION PRODUCTION CHANGES
Model and Year: 1984-86 VEHICLES EQUIPPED WITH THM 440T4 TRANSMISSIONS
TO: ALL CHEVROLET DEALERS
This bulletin provides three (3) changes incorporated in the 440T4 transmission.
3RD CLUTCH PLATE CHANGE
In 1985, 2.8L Chevrolet applications of the THM 440T4 changed to single-sided 3rd clutch plates. At the start of 1986 production, all THM 440T4 transaxles were built with single-sided clutch plates. When servicing 3rd clutch plates on any year/model 440T4, use the single-sided clutch plates. Refer to Figure 1 for transaxle identification information.
Service Parts Information:
Service Package, 3rd Clutch Plate Kit: P/N 8646938
Service Manual Reference:
Refer to the applicable service manual, THM 440T4 Automatic Transaxle Unit Repair Table of Contents, for 3rd clutch service information.
-TRANSAXLE IDENTIFICATION INFORMATION:
INPUT SHAFT SEAL ELIMINATION
All 1986 model THM 440T4 transaxles were built without an input shaft to 4th clutch shaft seal. When servicing a THM 440T4 built prior to 1986, it is not necessary to replace the input shaft to 4th clutch shaft seal. Refer to Figure 1 for transaxle identification information.
-REGULATOR VALVE SPRING:
CONVERTER CLUTCH REGULATOR VALVE SPRING ELIMINATED
At the start of 1986 production, the converter clutch regulator valve spring (refer to Figure 2, Item No. 394) was eliminated on the following models of the THM 440T4 transaxle: CFH, CHH, CMH, CNH, due to recalibration and fluid passage changes. Do not replace this spring on any listed model, as an increase of the apply feel of the transaxle converter clutch may result. Refer to Figure 1 for transaxle identification information.
Service Manual Reference:
Refer to the applicable service manual, THM 440T4 Automatic Transaxle Unit Repair Table of Contents, for control valve assembly service information.