ALL UTILITY VEHICLES WITH ROOF RACK (RPO V54 & V55)

SUBJECT: ROOF RACK HOWL/WIND NOISE

MODELS: ALL S/T UTILITY VEHICLES (JIMMY) WITH (RPO V54 OR V55) ROOF RACK

Some S/T Utility Vehicles (Jimmy) with options (RPO V54 or V55) roof racks may experience a roof rack howl. This howl has been determined to be caused by the height difference between the roof rack cross rails and the rubber strip within the rail. This condition results in a howl/wind noise as air flows across the rail, much like a reed in a wind instrument.

To eliminate this condition a new rubber cross rail cap (part # 15659287) should be installed. This new cap will repair the condition because it sits closer to the cross rail. See Figure 1 for the view of cross rail with installed rubber cap.

SERVICE PROCEDURE

1. Check cross rails for proper installation.

2. Remove and install cross rail, wide side forward (if required).

3. Mark old rubber cap to distinguish from new part (the new part is same as the old part, except for an increased width which is not detectable).

4. Remove old rubber cap.

5. Lube the new cross rail cap with mild soap and water or equivalent.

6. Slide in new rubber cap, wide side forward. (Cross rail does not need to be removed as the new part can be worked into place by hand.)

7. Test vehicle for howl condition.

In most cases only the front cross rail cap will be needed to eliminate the howl condition. However, if appropriate, this procedure may be applied to the rear cross rail cap as well.

NOTE: Install cross rail and cross rail cap with wide side forward as shown in Figure 1. Do not cut cross rail cap to fit, work into cross rail until all slack has been removed.

SERVICE PARTS INFORMATION Part Number Description Quantity 15659287 Rubber cross 1 per rail rail cap (as needed)

Parts are currently available through GMSPO.

WARRANTY INFORMATION

For vehicles repaired under warranty use:

Labor Operation: R2380 Labor Time: 0.4 hr.

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.