BRAKE SYSTEM CHANGE/ IMPROVED ASSIST

All 1988 Cimarrons built beginning with VIN breakpoint 502420 incorporate a master cylinder, booster, and calipers that are different from those parts installed prior to the breakpoint. The changes to the brake system were incorporated to provide an improved pedal feel and increased booster assist on initial brake apply.

1988 New 1988 Old Parts Information Part Numbers Part Numbers ----------------- ------------ ------------

Caliper 18015752 (Left) 18011667 (Left) 18015753 (Right) 18011668 (Right) Booster 18015498 (Code NT) 18013875 (Code LF) Master Cylinder 18015760 (Code NT) 18014370 (Code DL)

Parts Usage

The new caliper part numbers listed above must be used to service all 1988 Cimarrons from the start of 1988 production forward. The new brake booster and master cylinder part numbers listed in this bulletin must be used to service only those vehicles produced beginning with the VIN breakpoint listed above.

NOTE: Vehicles built prior to VIN breakpoint 502420 must be serviced with the old brake booster and brake master cylinder part numbers listed in this bulletin. Mixing the new booster and master cylinder parts with old parts on vehicles built prior to the VIN breakpoint may result in a brake application requiring increased pedal travel to stop the car.

Parts Identification

The new brake booster part number listed in this bulletin can be identified by the code letters "NT" printed on the bar code label which is attached to the part, refer to Figure 1, View A. The new master cylinder part number listed in this bulletin can be identified by the code letters "NT" stamped on the aluminum housing, refer to Figure 1, View C. The code letters "NT" are also printed on the bar code label attached to the rear of the brake fluid reservoir, refer to Figure 1, View B. The brake booster, master cylinder, and brake fluid reservoir must all have code letters "NT" on all vehicles built beginning with the VTN breakpoint listed in this bulletin.

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.