For 1990-2009 cars

# DRIVE AXLE 'WOBBLE' VIBRATION S-PLAN SPIDERS/BEARING BLOCKS

#### SUBJECT: DRIVE AXLE "WOBBLE" VIBRATION BETWEEN 30-55 km/h (INSTALL S-PLAN SPIDERS AND BEARING BLOCKS)

#### VEHICLES AFFECTED: 1988-92 "C, E AND K" MODELS

#### CONDITION:

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Some 1988-91 C/E/K models and 1992 C/E/K models before the following VIN breakpoints may experience an intermittent vibration with a light engine load between 30-55 Km/h. This "wobble" condition is often described as a side-to-side motion of the front of the vehicle, similar to when a belt is damaged in a radial tire.

1992 C/E/K VIN BREAKPOINTS ---------- --------------- Cadillac DeVille/Fleetwood N4331214

Cadillac Eldorado NU627469

Cadillac Seville NU835777

Oldsmobile E NU306007

Buick E NU410740

#### CAUSE:

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This condition is caused by an intermittent binding condition of the S-plan inboard drive axle joints. This binding condition only occurs while the joint is rotating at vehicle speed with an engine load. The S-plan joint will not cause a vibration on a closed throttle coastdown.

#### CORRECTION:

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This condition may be repaired by installing revised S-plan spiders and bearing blocks in both drive axles. The spider service kit, P/N 26039083, includes one spider, three bearing blocks, and two retaining clips. Two kits are required per vehicle. The revised spider incorporates polished surfaces and the bearing blocks have been enlarged. These changes went into production at the above breakpoints and will be incorporated in 1993 models as well.

Use the following service procedure:

1. Verify that the condition is not caused by tire imbalance. Refer to Section 3 of the appropriate Service Information Manual for tire balance diagnosis and repair.

2. Install two service spider kits (one per axle), P/N 26039083, following the service procedures in Section 4D of the appropriate Service Information Manual.

3. During joint disassembly, it is NOT necessary to remove the grease from the joint housing. The grease can be reused during reassembly with the new spider and bearing blocks.

For vehicles repaired under warranty use:

#### Models Cad-C Cad-E Cad-K Olds-E Buick-E

Labour Time: 1.8 1.7 1.7 1.6 1.6

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.