Celebrity V6-191 3.1L (1990)
Band: All Technical Service Bulletins
A/T - Intermittent Loss of Drive
Number:
90-17-7A
Section:
7A
Date:
June 1989
Subject:
INTERMITTENT LOSS OF DRIVE
Model and Year:
1984-90 A, W CAR WITH 440-T4 TRANSMISSION
Figure 1 - THM 440-T4/THM F-7 Transaxle Identification Information
TO:
ALL CHEVROLET DEALERS
A vehicle equipped with a THM 440-T4/HYDRA-MATIC 4T60 (Figure 1) transaxle may experience an intermittent loss of Drive. This may be caused
by the 1-2 band stop (139) being below specification allowing the band to shift off location causing the 1-2 Band Apply Pin to miss the Band while
stroking, creating a loss of drive. The vehicle will still have Reverse gear. If there is no Forward and Reverse gear, then it is most likely a damaged input
clutch sprag assembly.
Figure 2 - Removal Of Bottom Case Components
SERVICE PROCEDURES:
(Figures 2-6)
The 1-2 band stop (139) can be replaced while the transaxle is in the vehicle by removing the screws (60), transmission oil pan (59) and oil filter
assembly (58) as listed in the Service Manual, then:
