1-2 SHIFT SHUDDER - INSTALL NEW FIBER/STEEL CLUTCH PLATE

1985-87 6000 AND 1987 BONNEVILLE MODELS EQUIPPED WITH THM 440-T4 (ME9)

"This bulletin 87-7-20, dated 6/87, which should now be destroyed. The bulletin is being revised to add 1985-86 model years and to clarify when the service parts listed should be ordered. "

BULLETIN COVERS:

A 1-2 shift shudder on 1984-1987 vehicles equipped with a THM 440-T4 transaxle may be caused by out of flat 2nd clutch fiber plates. This condition may be repaired by replacing the 2nd clutch plates with the Service Packages described in the Service Parts Information section below.

DATE OF PRODUCTION CHANGE: (Figure 1) ------------------------- April 15, 1987 (Julian Date 105), all 1987 THM 440-T4 transaxles were built using the new 2nd clutch fiber plates. The new plates were also used in all Service Replacement Transmission Assembly (SRTA) models starting on April 15, 1987 (Julian Date 105).

SERVICE ACTION:

When servicing a THM 440-T4 transaxle for a 1-2 shift shudder condition or performing a complete overhaul, DO NOT use the 2nd clutch fiber plates from an overhaul package that has a D7 or earlier packaging Julian Date stamped on the carton. Refer to the Service Parts Information section below for an additional package to order. Overhaul packages with an E7 and later packaging date contain the new fiber plates and an additional package is not required.

SERVICE PARTS INFORMATION:

IMPORTANT: Only order the service package listed below if the overhaul package has a D7 or earlier packaging date. All overhaul packages that have an E7 or later packaging date have the new 2nd clutch fiber plates and there is no need to order the service package listed below.

Service Package Contents Application ------- -------- ----------- 8662913 2nd Clutch Plate Package 1985-1986 model years - (5) steel plates - (5) fiber plates 8662914 2nd Clutch Plate Package 1987 model year - (6) steel plates - (6) fiber plates

Parts are currently available from GMSPO.

SERVICE MANUAL REFERENCE:

Refer to the appropriate model year THM 440-T4 (ME9) Automatic Transaxle Unit Repair Table of Contents for 2nd Clutch Assembly service information.

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.