TCC BUSYNESS CAUSED BY EARLY 3-4 SHIFT/3-4 VALVE SPRING P/N

TRANSMISSION APPLICATIONS: SUBJECT: ------------------------- ------- 1986 THM 440-T4 (ME9) TORQUE CONVERTER CLUTCH (TCC) BUSINESS CAUSED BY EARLY 3-4 SHIFT

TRANSMISSION MODELS: VEHICLE APPLICATIONS: ------------------- -------------------- 6BAH, 6BBH, 6BDH, 6BHH, C, H CARS WITH 3.0L AND 3.8L ENGINES 6BLH, 6BMH

Bulletin Covers:

Torque converter clutch (TCC) busyness caused by an early 3-4 shift in 1986 of c of and, "H" cars, equipped with a 3.OL or 3.8L engine and THM 440-T4 transaxle, may be repaired by replacing the 3-4 throttle valve (T.V.) spring. Under light throttle, TCC releases during the shift raising engine r.p.m. momentarily (may be diagnosed as an engine flare), then TCC re-applies shortly after the shift is completed.

DATE OF PRODUCTION CHANGE:

Start of Production for all 1987 THM 440-T4 Transaxles.

SERVICE ACTION:

Inspect and adjust the T.V. cable following the procedures contained in the appropriate Service Manual and road test the vehicle. If the condition still exists, replace the 3-4 T.V. spring (Item, #348, Figure 1) contained in the service package described in the "Service Parts Information" section.

SERVICE PARTS INFORMATION:

Service Package No. Contents ------------------- -------- 8662934 (1) 3-4 Throttle Valve Spring (2) Spacer Plate Gaskets (1) Instruction Sheet

SERVICE MANUAL REFERENCE:

Refer to the On Car Service section and the THM 440-T4 Transaxle Unit Repair section in the appropriate model year service manual for repair procedures.

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.