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For 1990-2009 cars only

POPPING NOISE WHEN ACCEL/BRAKE WORN FRAME INSULATOR

VEHICLES AFFECTED: 1986 ELDORADOS AND SEVILLES WITH STANDARD SUSPENSION

Some 1986 Eldorados and Sevilles built before VIN breakpoints 611311 and 809049, with standard suspension may experience a snapping or popping noise when accelerating from a stop or during braking due to a worn #2 mount lower insulator. This condition may be caused by an over stressed #2 mount. A new #3 mount has been released to reduce stress on the #2 mount, see Figure 1.

To repair this condition, use the following service procedure.

1. Raise vehicle.

2. Install jack stands to support frame.

3. Remove bolt, retainer and lower insulator at #2 mount.

4. Inspect area where the insulator contacts the lip of the retainer (refer to Figure 1). If the insulator is not cut in this area, go to step 7. If it is cut, go to the next step.

5. Install a new #2 mount using the following parts:

Description Part No.

Insulator 1640304 Retainer 1640188

6. Torque bolt to 100 N.m (74 ft. lbs.) 7. Remove bolt and spacer at #3 mount.

8. Install a new #3 mount (Figure 1) using the following parts:

Description Part No.

Spacer 1638908 Insulator 25525868 Retainer 1640188 Bolt 14032535

9. Torque bolt to 100 N.m (74 ft. lbs.).

10. Remove jack stands.

11. Lower vehicle.

Use the most applicable labour operation from the Canadian Labour Time Guide and claim 0.6 hours.


Object Number: 84745  Size: FS

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.