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For 1990-2009 cars only

SHOCK GROAN ON 25MM NON-GAS CHARGED REAR SHOCKS

SUBJECT: SHOCK GROAN ON 25MM NON-GAS CHARGED REAR SHOCKS (REPLACE SHOCK ASSEMBLIES)

VEHICLES AFFECTED: 1991-93 "J, L, N" MODELS

APPLICATION:

----------- 1991-93 "J" Series with FE1 or FE2 Suspension

1991-93 "L" Series with FE1-B19 Suspension

1991-93 "N" Series with FE1 or FE2 Suspension

CONDITION:

--------- Some rear shocks may exhibit a groaning noise after the vehicle has been sifting stationary for an extended period of time. Shock groan usually disappears after driving the vehicle a short distance. This shock groan condition is sensitive to temperature and humidity.

CAUSE:

----- As the vehicle sits stationary for an extended period of time, the oil film on the shock rod dries. When this occurs, the shock rod and seal interface is dry during the first several compressions/extensions. As the shock begins to become lubricated, this condition disappears.

CORRECTION:

---------- Replace shock assemblies with gas charged shocks (P/N 22064490). These shocks contain pre-lubricated seals which will not exhibit shock groan

Allow vehicle to sit idle overnight. Before driving or moving the vehicle, press down on the rear bumper. If a groan is detected, install two shock absorber assemblies.

For vehicles repaired under warranty use:

Labor Operation: E-5807

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.