LeSabre V6-231 3.8L VIN C SFI (1990)
Drive Chain: All Technical Service Bulletins
A/T - Revised Driven Sprocket Support and Chain Scoop
Bulletin 90-7440-2
Date
Dec., '89
Ref.No. 90-038-7440
Corp.Ref.No. 977157
SUBJECT:
NEW DRIVEN SPROCKET SUPPORT AND CHAIN SCAVENGING SCOOP
MODELS AFFECTED: 1990 4T60 (THM 440-T4 AUTOMATIC TRANSAXLE)
Figure 1
CHANGE TO ASSEMBLY COMPONENTS (Figure 1)
A new driven sprocket support and chain scavenging scoop is used in production on 1990 Century, Electra/Park Avenue, Riviera, Reatta, LeSabre and
Regal models equipped with a HYDRA-MATIC 4T60 (THM 440-T4 Automatic Transaxle). The new driven sprocket support requires the chain
scavenging scoop to be about 1/3 the length of the previous scoop.
IMPORTANT:
The new driven sprocket support will service past models, but the new, shorter scavenging scoop must be used with it. The previous
scoop will not fit. Do not leave the scoop out. This will cause durability concerns.
Do not use the new, shorter chain scavenging scoop with the previous driven sprocket support assembly. This will also cause
durability concerns.
DATE OF PRODUCTION CHANGE
Starting August 16, 1989 (Julian Date 228), all HYDRA-MATIC 4T60 (THM 440-T4) transaxles will be built with the new driven sprocket support and
chain scavenging scoop.