REAR SUSPENSION THUD NOISE (REPLACE STRUT ASSEMBLIES)

Models Affected: 1988 GRAND PRIX

This bulletin cancels and replaces bulletin 88-3-30 issued 3/88. This bulletin has been revised to clarify the requirement that both struts must be replaced and also to clarify the use of Rear Suspension Auxiliary Spring Compressor tool.

Some 1988 Grand Prixs may exhibit a squeak or clunk noise during normal driving conditions or a thud type noise when turning onto an up ramp of a parking ramp/driveway or driving over a deep chuck-hole in the road.

The thud noise may be the result of the rear strut(s) extending to their maximum travel. Although not detrimental to the strut(s), the associated noise condition may be a cause of annoyance to some vehicle owners.

Vehicles exhibiting this condition may be repaired by installation of new rear struts and spring retention plates. These new strut assemblies provide additional rear suspension travel and are the only type now available for service. As a result, if strut replacement is required, both struts will have to be replaced. In addition to the above indicated part replacement, vehicle curb trim height ("K" dimension) should be checked to insure vehicle is at the correct curb trim height. Part replacement and trim height check should be performed following applicable service manual procedures.

Parts that are required for this installation are noted below:

Suspension Level Description P/N Quantity Required ---------------- ----------- ---- ----------------- Base Strut Unit 22064154 2

Up Level Strut Unit 22064155 2

All Spring Plate 10130115 2

Parts are currently available through GMSPO.

IMPORTANT: In order to replace rear strut assemblies, it is necessary to remove the rear auxiliary springs. Tool number J37956. Rear Suspension Auxiliary Spring Compressor must be used to compress the auxiliary spring. Do NOT use tool number J37098. Kent Moore has shipped J37956 to all dealers, and J37098 can be returned for full credit.

Warranty Information

Labor Operation Number: T1430

Labor Time : 1.3 Hours

Add : 1.0 Align Rear Suspension

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.