'STAR-BREAK' TYPE OF CRACKING SPORT SIDE REAR FENDER PAINT

SUBJECT: "STAR-BREAK" CRACKING OF SPORTSIDE REAR FENDER PAINT

MODELS: 1988-89 C/K

THIS BULLETIN CANCELS AND REPLACES GMC TRUCK SERVICE BULLETIN 89-T-07, DATED JANUARY 1989 (CORPORATE NUMBER 861004) TO REVISE PARTS INFORMATION. ALL COPIES OF 89-T-07 SHOULD BE DISCARDED.

Some 1988-89 C/K Sportside trucks have experienced star-break type cracking of the rear fender paint due to the impact of stones thrown from the tires.

To address this condition, a water borne inner fender impact protectant spray (P/N 9984226PS) and a Kent-Moore spray gun (J38337) are now available.

Perform the following service procedure when applying the water borne inner fender impact protectant to vehicles that exhibit this cracking paint condition on rear Sportside fenders.

PREPARATION

1. Raise the vehicle on a hoist and remove the rear wheels.

2. Clean inner fender wells using a coarse brush, water, prep sol (DuPont P/N 39295 or equivalent) and mineral spirits as needed to assure a clean inner fender surface (figure 1).

3. Shake the water borne protectant well before using.

SPRAY PROCESS

1. Attach the spray gun directly to the protectant container.

2. Hold the spray gun (J38337) with the nozzle at a 45 degree angle and 10 to 12 inches from the surface.

3. Spray at a 60 to 80 psi, and spray only the horizontal surface area above the tire (figure 1). Pressures above 80 psi will cause an excessive splatter pattern.

4. Apply one quart of protectant on each fender; allow the fender to set for one hour. Apply another half quart on each fender. (The protectant should have a thickness of 2mm-3mm when dry).

5. Clean the equipment and any over-spray with water.

It is important that the truck be allowed to sit for 36 hours in a warm, dry place to allow proper curing of protectant, prior to returning it to customer use.

NOTICE: You may accelerate dry time with air flow (fan). DO NOT use heat lamp to accelerate the curing process. Use of heat lamps may result in blistering or peeling of the protectant.

PAINT REPAIR

1. If a vehicle requires fender/paint repair, it may be processed for painting within eight hours of application of protectant spray. However, total cure time of the protectant must still be 36 hours before returning the vehicle to customer use.

2. Use standard procedure for repairing/painting SMC fenders.

PARTS INFORMATION

Water borne inner fender impact protectant spray (P/N 9984226PS) can only be ordered through Corrosion Consultants Incorporated at 1-800-999-7583 between 8:30 am-6:00 pm EST.

The inner fender protectant spray will be shipped to the dealer C.O.D. at a cost of $21.00 per case. Each case contains three quarts of protectant spray.

*IMPORTANT

This protectant spray is specifically designed for this application and must not be substituted.

Kent-Moore spray gun (J38337) should be ordered through Kent-Moore's order department 1-800-821-3036 or (313) 774-9500.

*IMPORTANT

The Kent-Moore spray gun (J38337) has been specifically designed for use with the water borne inner fender impact protectant spray. Due to the viscosity of the chemical spray involved, a special orifice is required to achieve the correct vacuum and siphon effect necessary for proper spray application. Other spray guns that may appear to be equivalent are not recommended.

VIN BREAKPOINTS

This condition was corrected in production beginning with the following VIN breakpoints:

GMC 1GTDC14H9KZ514166

WARRANTY INFORMATION

For vehicles under warranty use the following labor ops.

Labor Op. Description Time --------- ----------- ---- T7825 Application of Inner Fender 0.9 hrs. Protectant Spray

If vehicle required fender repair, use appropriate labor operation.

A9480 Fender Rear-Repair (Right) 0.5 hrs A9481 Fender Rear-Repair (Left) 0.5 hrs.

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.