HARSH ENGAGEMENT CONDITIONS SYMPTOMS/DIAGNOSIS/REPAIRS

1987-1988 VEHICLES EQUIPPED WITH THM 440-T4 (ME9) TRANSAXLE

VEHICLE APPLICATIONS:

Cutlass Ciera (A Carline), Delta 88 (H Carline), Ninety-Eight (C Carline), Toronado (E Carline), Cutlass Supreme (W Carline)

BULLETIN COVERS:

Harsh Engagement conditions and specific service information for 1987 and 1988 cars equipped with a THM 440-T4 transaxle. Other items which cause harsh engagement conditions are:

- Vacuum leaks (low vacuum supply to the vacuum modulator) 33-46 CM HG (13-18 in hg) required - Stuck modulator valve - Missing No. 9 checkball

DATE OF PRODUCTION CHANGE: (Figure 1) ------------------------------------- November 24, 1987 (Julian Date 328), all THM 440-T4 transaxles were built using a new 1-2 servo cushion spring, reverse servo cushion spring and reverse servo return spring.

SERVICE ACTION: (Figure 2) -------------------------- I. Harsh engagement from park or neutral to drive or reverse - A,C,H,E carlines without 2.8L engines

1. Remove the 1-2 servo assembly and the reverse servo assembly from the transaxle. 2. Disassemble and replace the 1-2 servo cushion spring (559) and the reverse servo cushion spring (549) with the correct part listed in the service parts information section. 3. Install the 1-2 servo assembly and reverse servo assembly in the transaxle.

II. Harsh engagement from reverse to drive, park or neutral to drive or reverse - 1987-1988 A carlines with 2.8L engines only, 1988 W carlines with 2.8L engines only.

1. Remove the 1-2 servo assembly and the reverse servo assembly from the transaxle. 2. Disassemble and replace the 1-2 servo cushion spring (559), the reverse servo cushion spring (549) and the reverse servo return spring (552) with the parts listed in the service parts information section. 3. Install the 1-2 servo assembly and reverse servo assembly in the transaxle.

SERVICE PARTS INFORMATION:

Part Number Description Usage ------- ----------- ------

8668121 Reverse Servo Cushion Spring (549) All 1987-88 Models 8668123 1 -2 Servo Cushion Spring (559) All 1987-88 Models 8668127 Reverse Servo Return Spring (552) 1987-88 Vehicles W/ 2.8L Engines Only

SERVICE MANUAL REFERENCE:

Refer to the THM 440-T4 (ME9) Automatic Transaxle On-Car Service section for appropriate service information.

SERVICE NOTES:

For warranty purposes, use applicable labor time and operation numbers.

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.