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A/T - New Governor Screen Added to Case

89buick03 Bulletin 89-7440-4 Date
Feb., '89
Ref. No. 89-064-7440 Corp. Ref. No. 877151
SUBJECT: NEW GOVERNOR SCREEN ADDED TO CASE.

MODELS AFFECTED: SOME 1989 VEHICLES EQUIPPED WITH THM 440-T4/HYDRA-MATIC 4T60 TRANSAXLES

BULLETIN COVERS

A new Governor Screen (3) was added to the Governor Shaft Sleeve in the Case. The Governor Screen will minimize the potential of sediment entering the Governor Assembly and preventing the Governor Balls from seating properly.

FIGURE 1 - THM 440-T4/THM F-7 TRANSAXLE IDENTIFICATION INFORMATION:




SERVICE ACTION (Figure 2)

A machining change in the Case to provide clearance for the Screen will not permit installation of the Screen in past model Cases.

Important: Do not attempt to drill previous design Cases in order to install a Governor Screen due to critical dimensions.

FIGURE 2 - NEW GOVERNOR SCREEN:




DATE OF PRODUCTION CHANGE (Figure 1)

The new Governor Screen will be used on some models for production starting November 30, 1988 (Julian Date 335) and will he used on all models December 5, 1988 (Julian Date 340).
SERVICE NOTES

This is the same Governor Screen as used in the THM 125C/HYDRA-MATIC 3T40.

SERVICE PARTS INFORMATION

Part No Description Model Year - Model Usage

8660770 Sleeve and Screen 1989-1/2 All
Assembly, Governor Shaft

8631328 Sleeve, Governor Shaft 1984-89-1/2 All
(no screen)

Parts are currently available from GMSPO.