On some 1989 DeVilles, Eldorados, Sevilles, and Allantes a production change has been made to add a screen to the governor shaft sleeve. The screen, which is identical to the one used in the THM 125C transaxle, was added to reduce the chance of sediment entering the governor assembly.
The production change occurred on some models beginning on November 30, 1988 (Julian date 335). The change occurred on all models by December 5, 1988 (Julian Date 340).
The Production change included dimensional changes in the case to provide clearance for assembly of the screen.
Service Parts Information
P/N Description Model Year --- ----------- ---------- 8660770 Sleeve and Screen Assembly, Governor Shaft 1989-1/2 8631328 Sleeve, Governor Shaft 1984-1989-1/2
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