BURNED OVERRUN CLUTCH 700R4 PLATE ASSEMBLY PROD. CHANGE

1982-1984 C, K, S, T, G WITH THM 700-R4 TRANSMISSIONS

Beginning April 16, 1984 (Julian Date 107) a new input housing and shaft assembly and oil pump assembly went into production for all models of the THM 700-R4 transmission. In addition, new torque converters went into production for all 298mm applications (4.1L inline V6; V-8 gas and diesel engines).

All transmissions built starting with Juliam Date 107 are stamped with the letter "T" on the pan rail after the transmission identification number (Figure No. 1). The letter "T" will only be used for the remainder of the 1984 model year.

These production changes eliminate the possibility of burned clutch packs in the input housing which may be due to harline cracks which could develop across the ring grooves in the turbine shaft. A crack in this area of the turbine shaft on models built prior to this change may cause one or any combination of the following clutches to slip and overheat due to loss of applied pressure.

A. Overrun clutch pack B. Forward clutch pack C. 3-4 clutch pack

Service Information

1. If any 1982, 1983 or 1984 THM 700-R4 transmission (built prior to Julian Date 107) experiences burned clutch packs within the input housing assembly, check for a possible cracked turbine shaft.

Important: A hairline crack in the turbine shaft is not always detected by visually inspecting the shaft. To determine if the shaft is cracked, inspect the slator shaft sleeve for possible score marks in the inner diameter (Figure No. 2). If scoring is found, the probable cause is a crack in the turbine shaft which opena under torque conditions and produces the scoring and burned clutch packs. If this condition is found, replace both the input housing and shaft assembly and the oil pump assembly complete. Due to recent changes in the oil pump cover and pump body castings, these parts are serviced as an assembly for 1982 through 1984.

2. Oil pump assemblies, input housing and shaft assemblies, and converters can be purchased separately as shown in the following charts, #1, #2, and #3, respectively. However any transmissions built prior to this change (1982, 1983, or 1984 not identified by a "T") must use the part numbers shown in the column marked "before Julian Date 107". Any 1984 transmission built after this change (identified by the letter "T") must use the part numbers in the column marked "after Julian Date 107".

3. Due to the changes made on the above parts, those shown for use prior to the change must not be interchanged with those shown for use after the change. Interchanging these parts will result in conditions such as:

A. Interference fits B. Loose fits C. No Drive D. Possible repeat cracks int he turbine shaft. E. Future confusion if the transmission should require additional service.

CHART 1

BEFORE STARTING YEAR MODELS PART NAME JULIAN DATE WITH JULIAN 107 DATE 107

1982 M2,M4,M5,M7,MB,MC OIL PUMP 8647967 MD,ME,TE,TH,T5,T6, TW,TC,TJ,TK

1982 M6,MH OIL PUMP 8647968 ASSY. COMPLETE

1983 TC,MB,MC,MJ,VN,TE, OIL PUMP 8647967 TH,TK,MD,ME,MW,VH ASSY. COMPLETE MK,VA,MP,ML,T7,MS T2

1983 TZ,T8,TP,MH,VJ,TL OIL PUMP 8647968 TS ASSY. COMPLETE

1984 MB,MC,MD,VH,TE,ME OIL PUMP 8647967 MK,MJ,VN,TC,TH,MW ASSY. COMPLETE TK,VA

1984 TL,TZ,TS,MR,TG,TD, OIL PUMP 8647968 8654309 ML,MP,MS,T2,T7

1984 MH,VX,VJ,VE,TM,T8 OIL PUMP MG ASSY. COMPLET 8647969 8654310

CHART 2

1982 M2,M4,M5,M7,MB,MC INPUT HOUSING *8647127 MD,ME,M6,MH,T5,56 AND SHAFT ASSY. (8647963) TC,TE,TH,TN,TP,TW, TJ,TK

1983 TC,MB,MC,MJ,VN,TE INPUT HOUSING *8647127 TH,TK,MD,ME,MW,VH AND SHAFT ASSY. (8647963) TZ,MK,T8,MH,VJ,TL, TS,TP

1983 T2,VA,ML,MS,T7,MP INPUT HOUSING *8647128 AND SHAFT ASSY (86479650)

1984 MB,MC,MD,VH,MR,TG, INPUT HOUSING *8647127 8654156 ME,MK,MJ,VN,TC,TH AND SHAFT ASSY (8647963) MW,TD,TK,MG,MH,VJ TL,TZ,T8,TE,TS,VX, VE,TM

1984 VA,MI,MP,MS,T7 INPUT HOUSING *8647128 9654155 AND SHAFT ASSY. (8647965)

*THESE PART NUMBERS WILL BE SUPERSEDED BY THE NUMBERS SHOWN IN ( ) Approx. In October, 1984

Torque converter assemblies for 1982, 1983 and 1984 models built priot to Julian date 107, use current release part numbers.

Torque converter assemblies for 1984 models starting with Julain Date 107, use the part numbers as shown in the chart below.

CHART 3

1964 MODEL TORQUE CONVERTER ASSEMBLY PART NUMBERS STARTING WITH JULIAN DATE 107

MG,MH,VX,VJ,VE,TM CONVERTER ASSY. 8647903 TZ,T8

MD,VH,MR,TG CONVERTER ASSY. 8647901 TE,ME,MK,TH, MW,TD,TK

MB,MC,MJ,VN,TC CONVERTER ASSY. 8647902

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.