GM Service Manual Online
For 1990-2009 cars only

NEW DESIGN LO AND REVERSE ASSY 125 TRANSMISSION

BEGINNING MID JULY, 1981, SOME 1982 THM 125 & 125C TRANSMISSION MODELS WERE ASSEMBLED WITH A NEW DESIGN LO & REVERSE CLUTCH ASSEMBLY. SEE FIGURE 1. THIS DESIGN CHANGE WILL PRODUCE A MORE DESIRABLE NEUTRAL TO REVERSE GARAGE SHIFT FEEL. THIS NEW DESIGN CONSISTS OF THE FOLLOWING: (REFER TO FIGURE 2) 1.A MODIFIED LO AND REVERSE PISTON, ELIMINATING THE NEED FOR AN APPLY RING. 2.A WAVED STEEL CLUTCH PLATE NEXT TO THE LO AND REVERSE PISTON, ELIMINATING ONE (1) FLAT STEEL CLUTCH PLATE. 3.A SMALLER LO AND REVERSE CLUTCH HOUSING FEED ORIFICE. SERVICE INFORMATION 1.THE FOLLOWING CHART CONTAINS THE NECESSARY SERVICE PACKAGE NUMBERS FOR ALL THM 125 & 125C TRANSMISSIONS. LO AND REVERSE CLUTCH ASSEMBLY SERVICE PACKAGE NUMBERS PART NAME HOUSING AND BUSHING LO AND REVERSE CLUTCH PAST DESIGN 1980-1981 8637514 NEW DESIGN 1982 PART NAME *HOUSING AND BUSHING LO & REVERSE CLUTCH (WITH PISTON & WAVED PLATE) NEW DESIGN 1982 8643921 PART NAME *LO & REVERSE CLUTCH PISTON AND APPLY RING ASSEMBLY PAST DESIGN 1980-1981 8631929 PART NAME LO & REVERSE CLUTCH PISTON ASM. (WITH WAVED PLATE 8637574) NEW DESIGN 1982 8643922 PART NAME STEEL CLUTCH PLATE PAST DESIGN 1980-1981 8631079 NEW DESIGN 1982 8631079 PART NAME WAVED CLUTCH PLATE NEW DESIGN 1982 8637574 PART NAME *A WAVED CLUTCH PLATE MUST BE USED WITH THE NEW DESIGN ONE PIECE PISTON.


Object Number: 78221  Size: FS


Object Number: 77451  Size: FS

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