CAMPAIGN: OUTER TIE ROD END NUTS LOOSE AND NOT CRIMPED

Model and Year: 1988 C/K 10-20 MODEL TRUCKS BUILT AT FT. WAYNE ONLY

The National Traffic and Motor Vehicle Sa'ety Act, as amended, provides that each vehicle which is subject to a recall campaign of this type must be adequately repaired within a reasonable time after the owner has tendered it for repair. A failure to adequately repair within 60 days after tender of a vehicle is prima facie evidence of failure to repair within a reasonable time.

If the condition is not adequately repaired within a reasonable time, the owners may be entitled to an identical or reasonably equivalent vehicle at no charge or to a refund of the purchase price less a reasonable allowance for depreciation.

To avoid having to provide these burdensome solutions, every effort must be made to promptly schedule an appointment with each owner and to repair their vehicle as soon as possible. As you will see in reading the attached copy of the letter which is being sent to owners, the owners are being instructed to contact the nearest Chevrolet Branch Office if their dealer does not remedy the condition within five days of the mutually agreed upon service date. If the condition is not remedied within a reasonable time, they are instructed on how to contact the National Highway Traffic Safety Administration.

DEFECT INVOLVED

General Motors has determined that a defect which relates to motor vehicle safety exists in some 1988 C/K 10-20 model trucks built at Ft. Wayne. One or both of the outer tie rod nuts may be loose and not crimped. A loss of one or both of these nuts could lead to the outer tie rod(s) disengaging from the steering knuckle resulting in a possible loss of steering control which could lead to a vehicle crash without prior warning.

To prevent this condition from occurring it will be necessary to inspect the outer tie rod nuts for crimping on all involved vehicles. If a non-crimped nut is found, the tie rod and knuckle are to be replaced and the toe-in set.

VEHICLES INVOLVED

Involved are certain 1988 C/K 10-20 model trucks built at Ft. Wayne within the following VIN breakpoints:

MODEL ASSEMBLY YEAR PLANT FROM THROUGH ---- ----- ---- ------- 1988 Ft. Wayne JZ100903 JZ103781

Involved vehicles have been identified by Vehicle Identification Number Computer Listings. Computer listings contain the complete Vehicle Identification Number, owner name and address data, and are furnished to the involved dealers with the campaign bulletin. Owner name and address data furnished will enable dealers to follow-up with owners involved in this campaign.

These listings may contain owner names and addresses obtained from State Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other purpose is a violation of law in several states. Accordingly, you are urged to limit the use of this listing to the follow-up necessary to complete this campaign. Any dealer not receiving a computer listing with the campaign bulletin has no involved vehicles currently assigned.

OWNER NOTIFICATION

Owners will be notified of this campaign on their vehicles by Chevrolet Motor Division (see copy of Owner Letter included with this bulletin).

DEALER CAMPAIGN RESPONSIBILITY

Dealers are to service all vehicles subject to this campaign at no charge to owners, regardless of mileage, age of vehicle, or ownership, from this time forward.

Whenever a vehicle subject to this campaign is taken into new or used vehicle inventory, or it is in your dealership for service in the future, you should take the steps necessary to be sure the campaign correction has been made before reselling or releasing the vehicle.

Owners of vehicles recently sold from your new vehicle inventory are to be contacted by the dealer, and arrangements made to make the required correction according to instructions contained in this bulletin.

PARTS INFORMATION

Parts required to complete this correction are to be obtained from General Motors Service Parts Operations (GMSPO). To ensure these parts will be obtained as soon as possible, they should be ordered from GMSPO on a C.I.O. order with no special instruction code, but on an advise code (2).

PART NUMBER DESCRIPTION QUANTITY ------ ----------- -------- 11514337 Cotter Pin - Ball Joint 2(Each side to Knuckle as required) 26000150 Tie Rod Asm-Outer (Left & Right) 1(Each side as required) 1052535 Brake Fluid (16 oz) 1

C10 15589409 Steering Knuckle Asm-L.H. 1 15589410 Steering Knuckle Asm-R.H. 1 3965092 Seal - Front Wheel 1(Each side as required)

C20 15589433 Steering Knuckle Asm-L.H. 1 15589434 Steering Knuckle Asm-R.H. 1 3965092 Seal - Front Wheel 1(Each side as required)

K10-20 15608671 Steering Knuckle Asm-L.H. 1 15608672 Steering Knuckle Asm-R.H. 1

SERVICE PROCEDURE

Inspect tie rod outer ball joint nuts, Figure No. 1 & 3 Item 1, for crimp marks. A properly torqued nut will have small indentations on the flat sides of the nut. Check both sides of the vehicle.

If there are crimp marks in the nuts no further action is required. The nuts were properly torqued in production. If there are no crimp marks in the nuts, the nuts are loose. In this case the outer tie rods and steering knuckles must be replaced. The service procedure for replacement of these parts is listed below.

2-WHEEL DRIVE

Refer to Figure No. 1 & 2 and Section 3, steering, suspension, wheels and tires, and 5, brakes of the 1988 C/K Pick-Up Truck Service Manual (ST-375-88).

1. Siphon 2/3 of the brake fluid from the master cylinder. 2. Lift and support vehicle. 3. Remove the tire and wheel assembly. 4. Remove the brake caliper from the hub/disc. Suspend the caliper assembly with a wire hook away from the work area. 5. Remove the wheel bearing cap, nut, and washer from the spindle. 6. Remove the hub/disc. Care should be used so that the outer bearing is not damaged. Save the inner and outer bearing cone and rollers. 7. Remove the splash shield and gasket. 8. Remove tie rod ball stud from the knuckle using tool J24319-01. 9. Remove the other end of the tie rod from the adjuster tube. Save the clamp and nut. 10. Remove the inner wheel bearing seal. 11. Remove the upper and lower ball studs from knuckle. Use tool J36607.

FLOOR JACK MUST REMAIN UNDER CONTROL ARM SPRING SEAT DURING REMOVAL AND INSTALLATION TO RETAIN THE SPRING AND CONTROL ARM IN POSITION.

12. Position a floor jack under the lower control arm near the spring seat. Raise the jack until it just supports the lower control am. 13. Remove the knuckle. 14. Install new knuckle. Torque upper ball joint nut to 90 Nm (66 lb.ft), and the lower ball joint nut to 128 Nm (94 lb.ft). Tighten the nuts to align the cotter pins. Do not tighten more than 1/6 turn. Install new cotter pins. 15. Reinstall splash shield gasket. 16. Reinstall splash shield. Torque bolts to 16 Nm (12 lb.ft). 17. Install new outer tie rod to the adjuster tube. The number of threads on both the inner and outer rod ends must be within three threads. The clamp and bolt should be positioned as shown in Figure No. 1. 18. Seat the tie rod ball stud in the knuckle using tool J29193. Torque bolts to 54 Nm (40 lb.ft). 19. Reinstall hub disc to the spindle using a new inner wheel bearing seal. Refer to hub, bearing & seal replacement, section 3C-11 of the service manual. 20. Apply grease to the outboard side of the outer bearig. Reinstall nut and washer to the spindle. Tighten nut to 16 Nm 12 lb.ft) while turning the hub/disc forward by hand. Adjust the nut to a 'Just loose' position by hand, then back the nut off until the hole in the spindle aligns with a slot in the nut. Do not back the nut off more than 1/2 flat. Install new cotter pin. 21. Reinstall cap to the hub/disc. 22. Reinstall brake caliper. Torque caliper mounting bolts to 38 Nm (28 lb.ft). 23. Reinstall wheel and tire assembly. Torque nuts to 123 Nm (90 lb.ft). 24. Repeat required steps to replace outer tie rod and knuckle on opposite side of truck, if required. 25. Lube tie rod ball studs with chassis lubricant P/N 1052497 or equivalent. 26. Lower vehicle. 27. Refill master cylinder with Delco Supreme II, P/N 1052535, or Dot 3 brake fluid and bleed brake system if required. 28. Readjust the toe-in. The Service Manual specifications are incorrect. The correct specifications are listed in Figure 5 page 10. Torque clamp nut at rod adjuster tube to 20 Nm (15 lb.ft.) 29. Install Campaign Identification Label.

4-WHEEL DRIVE

Refer to Figure No. 3 & 4 and 1988 C/K Pick-Up Truck Service Manual (ST-375-88), Sections 3 & 5.

1. Siphon 2/3 of the brake fluid from the master cylinder. 2. Lift and support vehicle. 3. Remove the tire and wheel assembly. 4. Remove the brake caliper from the disc. Suspend the caliper assembly with a wire hook away from the work area. 5. Remove the brake disc. 6. Remove the nut and washer from the axle shaft. 7. Remove the six bolts attaching the axle shaft to the differential. 8. Using an appropriate puller push the axle shaft back into the hub to free the shaft. 9. Remove the hub and bearing assembly. 10. Remove the splash shield and gasket from the knuckle. 11. Remove tie rod ball stud from the knuckle. Use tool J24319-01. 12. Remove the other end of the tie rod from the adjuster tube. Save the clamp and nut. 13. Remove and retain the knuckle seal. 14. Remove the upper and lower ball studs from the knuckle. Use tool J36607.

FLOOR JACK MUST REMAIN UNDER THE LOWER CONTROL ARM DURING REMOVAL AND INSTALLATION OF THE KNUCKLE.

15. Position a floor jack under the lower control arm. Raise the jack until it just supports the lower control arm. 16. Remove the knuckle. 17. Install new knuckle. Torque upper ball joint nut to 90 Nm (66 lb.ft) and the lower ball joint nut to 128 Nm (94 lb.ft). Tighten the nuts to align the cotter pins. Do not tighten more than 1/6 turn. Install new cotter pins. 18. Reinstall axle shaft bolts to the differential. Torque bolts to 80 Nm (59 lb.ft). 19. Reinstall knuckle seal. 20. Reinstall splash shield. Torque bolts to 16 Nm (12 lb.ft). 21. Install new outer tie rod to the adjuster tube. The number of threads on both the inner and outer rod ends must be within three threads. The clamp and bolt should be positioned as shown in Figure No. 3. 22. Seat the tie rod ball stud in the knuckle using tool J29193. Torque nut to 54 Nm (40 lb.ft). 23. Reinstall hub and bearing assembly. Tighten bolts to 90 Nm (66 lb.ft). 24. Install washer and nut on axle shaft. Tighten nut to 235 Nm (173 lb.ft). 25. Reinstall brake disc and caliper. Tighten caliper mounting bracket bolts to 38 Nm (28 lb.ft). 26. Reinstall wheel and tire assembly. Torque nuts to 123 Nm (90 lb.ft). 27. Repeat required steps to replace outer tie rod and knuckle on opposite side of truck, if required. 28. Lube tie rod ball studs with chassis lube P/N 1052497 or equivalent. 29. Lower vehicle. 30. Refill master cylinder with Delco Supreme II, P/N 1052535, or Dot 3 brake fluid and bleed brake system if required. 31. Readjust the toe-in alignment. The Service Manual specifications are incorrect. The correct specifications are listed in Figure 5 page 10. Torque clamp nut at tie rod adjuster tube to 20 Nm (15 lb. ft). 32. Install Campaign Identification Label.

CAMPAIGN IDENTIFICATION LABEL

Each vehicle corrected in accordance with the instructions outlined in this Product Campaign Bulletin will require a "Campaign Identification Label." Each label provides a space to include the five digit dealer code of the dealer perfoming the campaign service. This information may be inserted with a typewriter or ballpoint pen.

Each "Campaign Identification Label" is to be located on the radiator core support in an area which will be visible when the vehicle is brought in for periodic servicing by the owner.

Apply "Campaign Identification Label" only on a clean dry surface.

CLAIM INFORMATION

Submit a Product Campaign Claim with the information indicated below:

* Failed Parts Labor Lab Oth Repair Performed PC Part No. Allow FC OP Hrs Hrs ---------------- -- -------- ----- -- ----- --- ---

Inspect outer tie ** 00 V4170 0.2 0.1 rod nuts - both sides. No further action required

Inspect outer tie 6 11514337 ** 00 V4171 1.4 0.1 rod nuts. Replace tie rod end & knuckle & set toe-in - (C model) one side

Inspect outer tie 11 11514337 ** 00 V4172 2.2 0.1 rod nuts. Replace tie rod end & knuckle & set toe-in (C model) both sides

Inspect outer tie 5 11514337 ** 00 V4173 1.9 0.1 rod nuts. Replace tie rod end & knuckle & set toe-in (K model) one side

Inspect outer tie 9 11514337 ** 00 V4174 3.2 0.1 rod nuts. Replace tie rod end & knuckle & set toe-in (K model) both sides

*Campaign Administrative Allowance

**The "Parts Allowance" should be the sum total of the current GMSPO Dealer, Net price plus 30% of all parts required for the repair.

Dealers will automatically receive the correct labor and material allowance based on the labor operation performed.

Refer, to the Chevrolet Claims Processing Manual for details on Product Campaign Claim submission.

Dear Chevrolet Owner:

This notice is being sent to you in accordance with the requirements of the National Traffic and Motor Vehicle Safety Act.

REASON FOR THIS RECALL

General Motors has detemined that a defect which relates to motor vehicle safety exists in some 1988 C/K 10-20 model trucks built at Ft. Wayne. One or both of the outer tie rod nuts may be loose and not crimped. A loss of one or both of these nuts could lead to the outer tie rod(s) disengaging from the steering knuckle resulting in a possible loss of steering control which could lead to a vehicle crash without prior warning.

WHAT WE WILL DO

To prevent this condition from occurring it will be necessary to inspect the outer tie rod nuts for crimping. If a non-crimped nut is found, the tie rod and knuckle are to be replaced and the toe-in set. This service will be completed for you at no charge.

WHAT YOU SHOULD DO

Please contact your Chevrolet dealer as soon as possible to arrange a service date. Instructions for perfoming this service have been sent to your dealer. It is estimated that parts will be available to your dealer on September 1, 1987. The inspection will take approximately 15 minutes and an additional 1-1/2 to 3 hours may also be needed if tie rod and knuckle replacement is required. Please ask your dealer if you wish to know how much additional time is needed to process your vehicle.

Your Chevrolet dealer is best equipped to obtain parts and provide service to ensure your vehicle is inspected and/or corrected as promptly as possible. However, if you take your vehicle to your dealer on the agreed service date and they do not service this condition on that date or within five days, we recommend you contact your nearest Chevrolet Branch Office by telephone. The Branch Office will assist you and your dealer in getting your vehicle serviced. The telephone numbers of the Branch Offices are listed in your Owner's Manual.

After contacting your dealer and the Branch Office, if you are still not satisfied that we have done our best to remedy this condition without charge within a reasonable time, you may wish to write the Administrator, National Highway Traffic Safety Administration, 400 Seventh Street, S.W., Washington, D.C. 20590, or call 800-424-9393 (Washington, D.C. residents use 426-0123).

The enclosed owner reply card identifies your vehicle. Presentation of this card to your dealer will assist in making the necessary correction to your vehicle in the shortest possible time. If you have sold or traded your vehicle, please let us know by completing the postage paid owner reply card and returning it to us.

We are sorry to cause you this inconvenience; however, we have taken this action in the interest of your safety and continued satisfaction with our products.

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.