Product Safety Recall - Rear Axle Anchor Plate Fracture

General Motors has decided that a defect which relates to motor vehicle safety exists in certain 2003 Chevrolet and GMC C4500 medium duty trucks equipped with an 11,000# rear axle (GL4). Some of these vehicles have a condition where the rear axle anchor plate may fracture. As the anchor plate fractures, there is an audible "bang." If this indication of a condition requiring the driver's attention went unnoticed or was ignored, and if the vehicle was subjected to certain rebound, braking, or cornering maneuvers, the rear axle would be free to move fore and aft and provide unexpected steering inputs to the vehicle. If this happens while the vehicle is moving, and the driver is unable to react to these inputs, a crash could result.

Dealers are to install a new rear axle anchor plate and spacer.

Important: Some of the vehicles involved in this recall are also involved in Customer Satisfaction Program 02033. Incorrect Axle Pinion Angle. Both repairs are addressed in the service procedure contained in this bulletin.

Involved are certain 2003 Chevrolet and GMC C4500 medium duty trucks equipped with an 11,000# rear axle (GL4) and built within these VIN breakpoints:

Important: Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) or GM Access Screen (Canada only) before beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]

Involved vehicles have been identified by Vehicle Identification Number. Computer listings containing the complete Vehicle Identification Number, customer name and address data have been prepared, and are being furnished to involved dealers with the recall bulletin. The customer name and address data furnished will enable dealers to follow-up with customers involved in this recall. Any dealer not receiving a computer listing with the recall bulletin has no involved vehicles currently assigned.

These dealer listings may contain customer names and addresses obtained from Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other purpose is a violation of law in several states/provinces/countries. Accordingly, you are urged to limit the use of this listing to the follow-up necessary to complete this recall.

Important: Parts listed below are for this recall 02028 (Rear Axle Anchor Plate Fracture) and Customer Satisfaction Program 02033 (Incorrect Axle Pinion Angle).

Parts required to complete this recall are to be obtained from General Motors Service Parts Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal orders should be placed on a DRO=Daily Replenishment Order. In an emergency situation, parts should be ordered on a CSO= Customer Special Order.

The following service procedure covers the replacing of both rear suspension anchor plates and adding a new spacer. In addition, this service procedure includes changing the pinion angle of the rear differential for vehicles involved in Customer Satisfaction Program 02033 (Incorrect Axle Pinion Angle).

Caution: If using a hoist when performing this procedure, use suitable jack stands or equivalent to support the rear axle assembly prior to removal of any fasteners.

1. If equipped with a rear stabilizer bar, from underneath the vehicle, remove the nuts and bolts that attach it to the left and right side rear suspension anchor plates. (6).

Caution: When removing the nuts and washer in the next step, do not allow the anchor plate to drop.

2. On the right side of the vehicle, remove the four nuts and washers that attach the two U-bolts (1) to the right anchor plate (6). Do not reuse the nuts and washers.

Important: For a vehicle involved in Customer Satisfaction Program 02033 (Incorrect Pinion Angle), make note of the orientation or how the lower spring seat is positioned prior to removal in the next step.

3. Remove the anchor plate (6) and the lower spring seat (5). Do not reuse the anchor plate.

•	If the vehicle is involved in Customer Satisfaction Program 02033 (Incorrect Pinion Angle), do not reuse the lower spring seat.

•	If the vehicle is NOT involved in Customer Satisfaction Program 02033, the lower spring seat will be reused.

4. Remove both U-bolts (1). Do not reuse.

•	If the vehicle is involved in Customer Satisfaction Program 02033 (Incorrect Pinion Angle), proceed to Step 5.

•	If the vehicle is NOT involved in Customer Satisfaction Program 02033. proceed to Step 9.

5. Using a suitable floor jack placed under the right frame rail, raise and support the frame so that the upper spring seat (3) located between the top of the axle tube and the bottom of the leaf spring can be removed. If using a hoist, it will be necessary to either raise the frame or lower the rear axle.
6. Make note of the orientation or how the upper spring seat (3) is positioned and then remove. Do not reuse.
7. Properly position the install the new upper spring seat between the leaf spring and axle tube.
8. Lower the frame or raise the axle onto the new upper spring seat.
9. Install the new U-bolts over the leaf spring.

Important: For vehicles involved in Customer Satisfaction Program 02033 (Incorrect Pinion Angle), install a NEW lower spring seat in the next step. If the vehicle is NOT involved in Customer Satisfaction Program 02033, reuse the original lower spring seat.

10. Properly position and install the lower spring seat (5).
11. Install the new spacer (7) and new anchor plate (6).
12. Install new washers and nuts on the U-bolts and tighten. Do NOT tighten the nuts until instructed to later in this procedure.
13. Repeat Steps 2-12 on the left side of the vehicle.
14. Using a "cross" or "X" pattern, progressively tighten the nuts on all 4 U-bolts in 3 steps.

14.1.

First, tighten each nut to 100 N·m (74 lb ft).

14.2.

Second, tighten each nut to 184 N·m (136 lb ft).

14.3.

Third, tighten each nut to 300 N·m (221 lb ft).

15. If equipped, install the stabilizer bar to the right and left anchor plates and install the bolts and nuts.

Tighten
Tighten to 50 N·m (37 lb ft).

16. Install the GM Recall/Customer Satisfaction Identification Label(s), as required.

Place a Recall Identification Label on each vehicle corrected in accordance with the instructions outlined in this Product Recall Bulletin. Each label provides a space to include the recall number and the five (5) digit dealer code of the dealer performing the recall service. This information may be inserted with a typewriter or a ball point pen.

Put the Recall Identification Label on a clean and dry surface of the radiator core support in an area that will be visible to people servicing the vehicle. When installing the Recall Identification Label, be sure to pull the tab to allow the adhesion of the clear protective covering. Additional Recall Identification Labels for US dealers can be obtained from Dealer Support Materials by either ordering on the web from DWD Store, gm-dealerworld.com, or calling 1-866-700-0001 (Monday-Friday, 8:00 am to 5:00 pm EST). Request Item Number S-1015 when ordering.

Place a Recall Identification Label on each vehicle corrected in accordance with the instructions outlined in this Product Recall Bulletin. Each label provides a space to include the recall number and the five (5) digit dealer code of the dealer performing the recall service. This information may be inserted with a typewriter or a ball point pen.

Put the Recall Identification Label on a clean and dry surface of the radiator core support in an area that will be visible to people servicing the vehicle. Additional Recall Identification Labels for Canadian dealers can be obtained from DGN by calling 1-800-668-5539 (Monday-Friday, 8:00 am to 5:00 pm EST). Ask for Item Number GMP 91 when ordering.

Submit a Product Recall Claim with the information indicated below:

Refer to the General Motors WINS Claims Processing Manual for details on Product Recall Claim Submission.

Customers will be notified of this recall on their vehicles by General Motors (see copy of customer letter included with this bulletin).

The US National Traffic and Motor Vehicle Safety Act provides that each vehicle which is subject to a recall of this type must be adequately repaired within a reasonable time after the customer has tendered it for repair. A failure to repair within sixty 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 customer 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 remedies, every effort must be made to promptly schedule an appointment with each customer and to repair their vehicle as soon as possible. In the recall notification letters, customers are told how to contact the US National Highway Traffic Safety Administration if the recall is not completed within a reasonable time.

FOR ALL

All unsold new vehicles in dealers' possession and subject to this recall MUST be held and inspected/repaired per the service procedure of this recall bulletin BEFORE customers take possession of these vehicles.

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

Customers who have recently purchased vehicles sold from your vehicle inventory, and for which there is no customer information indicated on the dealer listing, are to be contacted by the dealer. Arrangements are to be made to make the required correction according to the instructions contained in this bulletin. This could be done by mailing to such customers a copy of the customer letter accompanying this bulletin. Recall follow-up cards should not be used for this purpose, since the customer may not as yet have received the notification letter.

In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your dealership for service in the future, please take the steps necessary to be sure the recall correction has been made before selling or releasing the vehicle.

Dear General Motors Customer:

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

General Motors has decided that a defect which relates to motor vehicle safety exists in certain 2003 Chevrolet and GMC C4500 medium duty trucks equipped with an 11,000# rear axle. Some of these vehicles have a condition where the rear axle anchor plate may fracture. As the anchor plate fractures, there is an audible "bang." If this indication of a condition requiring the driver's attention went unnoticed or was ignored, and if the vehicle was subjected to certain rebound, braking, or cornering maneuvers, the rear axle would be free to move fore and aft and provide unexpected steering inputs to the vehicle. If this happens while the vehicle is moving, and the driver is unable to react to these inputs, a crash could result.

Your dealer will install a new rear axle anchor plate and spacer. This service will be performed for you at no charge .

The length of time required to perform this service correction is approximately fifty-five minutes. Additional time may be required to schedule and process your vehicle. If you dealer has a large number of vehicles awaiting service, this additional time may be significant. Please ask your dealer if you wish to know how much additional time will be needed to schedule, process and repair your vehicle.

Please contact your dealer as soon as possible to arrange a service date. Instructions for making this correction have been sent to your dealer.

Your dealer is best equipped to obtain parts and provide services to correct your vehicle as promptly as possible. Should your dealer be unable to schedule a service date within a reasonable time, you should contact the GMICT Customer Assistance Center at 1-800-862-4389.

If, after contacting the GMICT, you are still not satisfied that we have done our best to remedy this condition without charge and within a reasonable time, you may wish to write the Administrator, National Highway Traffic Safety Administration, 400 Seventh Street SW, Washington, DC 20590 or call 1-888-327-4236.

The attached customer reply card identifies your vehicle. Presentation of this card to your dealer will assist in making the necessary correction in the shortest possible time. If you no longer own this vehicle, please let us know by completing the attached and mailing it in the postage paid envelope.

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 Isuzu Commercial Truck

Enclosure