Some 1982 through early 1985 THM 700-R4 Model transmissions may experience a firm or harsh 1-2 shift.
The charts below show the model year, transmission models, service package part numbers and package contents. Also, the charts below show the Julian dates when the new parts went into production for the 1985 models listed.
If a firm or harsh 1-2 shift condition is experienced on any of the 1982 through 1985 models built before the shown Julian dates, install the part(s) in the service package. Each package will contain the part(s) and instruction sheet for the models being serviced.
Refer to the proper Service Manual for correct parts installation procedures.
1983 TD, PQ 8647973 -1-2 ACCUMULATOR VALVE SPRING -INSTRUCTION SHEET
1983 YH NOTE: REMOVE AND DISCARD CURRENT 1-2 ACCUMULATOR VALVE SPRING AND DO NOT REPLACE IT. 1983 ML, MP, MS, T2, T7, 8647975 -1-2 ACCUMULATOR VA, YF VALVE SPRING -INSTRUCTION SHEET 1983 MB, MC, MD, ME, MH, 8647974 -1-2 ACCUMULATOR MK, MJ, MW, T8, TC, VALVE SPRING TE, TH, TK, TP, TS, -INSTRUCTION SHEET VH, VJ, VN, Y9, YC, YK, YN, YP
1983 YG 864797b -1-2 ACCUMULATOR VALVE -1-2 ACCUMULATOR VALVE SPRING -1-2 ACCUMULATOR SLEEVE -INSTRUCTION SHEET 1983 TL, TZ 8647981 -1-2 ACCUMULATOR VALVE SPRING -T.V. SPRING -INSTRUCTION SHEET 1984 TL, TZ 8647981 -1-2 ACCUMULATOR VALVE SPRING -T.V. SPRING -INSTRUCTION SHEET 1984 MD, ME, MK, MW, TE, 8647977 -1-2 ACCUMULATOR TK, YK, YP VALVE SPRING -1-2 ACCUMULATOR PISTON SPRING -INSTRUCTION SHEET
1984 MB, MC, MG, MH, MJ, 8647974 -1-2 ACCUMULATOR MR, PQ, T8, TC, TD, VALVE SPRING TG, TH, TM, V3, VH, -INSTRUCTION SHEET VJ, VN, Y6, Y7, Y8 Y9, YA, YB, YG, YN, YW
1984 ML, MP, MS, T7, VA, 8647975 -1-2 ACCUMULATOR YF VALVE SPRING -INSTRUCTION SHEET
1984 YH 8647978 -1-2 ACCUMULATOR VALVE -1-2 ACCUMULATOR SLEEVE -INSTRUCTION SHEET
1985 YX 8647979 -1-2 ACCUMULATOR VALVE -1-2 ACCUMULATOR SLEEVE -INSTRUCTION SHEET
1985 PQ, PR, MT, MS, ML, 8647975 -1-2 ACCUMULATOR MP, T7, VC VALVE SPRING -INSTRUCTION SHEET
1985 YK 8647988 -1-2 ACCUMULATOR VALVE SPRING -RING-OIL SEAL INNER (2ND APPLY PISTON); -HOUSING-SERVO PISTON INNER -PISTON-2ND APPLY -3-2 CONTROL SPRING* -1-2 ACCUMULATOR PISTON SPRING INSTRUCTION SHEET
* NOTICE: THE 3-2 CONTROL SPRING IS FOR POSSIBLE HARSH 3-2 DOWNSHIFT FEEL.
1985 MD, ME, MG, MH, MK, 8647977 -1-2 ACCUMULATOR MM, MR, MW, KX, TD, VALVE SPRING TE, TC, TK, TM, TW, -1-2 ACCUMULATOR T8, VE, VF, VG, VJ, PISTON SPRING VZ, YD, Y6 -INSTRUCTION SHEET
1985 VK, VL 8649962 -1-2 ACCUMULATOR VALVE SPRING -1-2 ACCUMULATOR VALVE -1-2 ACCUMULATOR VALVE SLEEVE -1-2 ACCUMULATOR PISTON SPRINC -INSTRUCTION SHEET 1985 YA, YC, YZ 8649966 -1-2 ACCUMULATOR VALVE SPRINC -1-2 ACCUMULATOR VALVE SLEEVE -INSTRUCTION SHEET 1985 YP 8649967 -1-2 ACCUMULATOR VALVE SPRING -1-2 ACCUMULATOR VALVE -1-2 ACCUMULATOR VALVE SLEEVE -INSTRUCTION SHEET 1985 Y8 8649968 -1-2 ACCUMULATOR VALVE SPRING -1-2 ACCUMULATOR VALVE -1-2 ACCUMULATOR VALVE SLEEVE -1-2 ACCUMULATOR PISTON SPRING -INSTRUCTION SHEET
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.