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A/T - THM 125C Auxiliary Valve Body

TSB: 88-13 (Mar)

THM 125C

SUBJECT: Auxiliary Valve Body




The 1987 THM 125C has a different auxiliary valve body, and uses a different auxiliary valve body gasket. The part number for the 1987 model gasket Is 8660789. Using an earlier gasket on the 1987 models will result in no vehicle movement. Before installing a stronger spring on the converter regulator valve on the 1987 units, check the valve. MANY 1987 UNITS ELIMINATED THE CONVERTER REGULATOR VALVE and are using an orifice control valve in its former location. Changing the spring on the orifice control valve will have no effect on the TCC application, but will affect the 3-2 downshift. See Figure for valve and gasket identification.