Customer Satisfaction - Low Engine Oil Light Inoperative

General Motors has decided that certain 2003-2004 model year Chevrolet and GMC W3500/4500 Series and Isuzu NPR/NPR-HD vehicles equipped with a 6.0L gas engine (LQ4) may have an insufficient ground to the oil pressure switch. This condition can prevent the engine oil pressure warning light from illuminating when the vehicle is started and when the engine oil pressure falls below normal during vehicle operation.

Dealers are to add an oil cooler ground harness.

Involved are certain 2003-2004 model year Chevrolet and GMC W3500/4500 Series vehicles and Isuzu NPR/NPR-HD vehicles equipped with a 6.0L gas engine (LQ4) and built within these VIN breakpoints:

Important: Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) prior to beginning program repairs. [Not all vehicles within the above breakpoints may be involved.]

For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete Vehicle Identification Number, customer name and address data has been prepared and will be loaded to the GM DealerWorld, Recall Information website. Dealers that have no involved vehicles currently assigned will not have a report available in GM DealerWorld.

The Campaign Initiation Detail Report 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 report to the follow-up necessary to complete this program.

For GM Models

Parts required to complete this program are to be obtained from General Motors Service Parts Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering requirements. 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.

For Isuzu Models

Parts required to complete this program are to be obtained from American Isuzu Parts Distribution Network (AIPDN). Please refer to your "involved vehicles listing" prior to ordering requirements.

1. Turn the vehicle off and set the parking brake.



2. Loosen the oil cooler mounting bolt (1).
3. Clean underneath the oil cooler mounting bolt head.
4. Clean the stud and nut (2) for the shift cable clamp.



5. Place the closed end of the ground harness (3) over the shift cable clamp mounting bolt end (2).
6. Secure the harness to the mounting bolt with the nut provided in the kit.

Tighten
Tighten to 22 N·m (16 lb ft).

7. Slip the open end of the harness under the oil cooler mounting bolt head (1).

Tighten
Tighten to 21 N·m (15 lb ft).

8. Insert the key into the ignition and turn the ignition to ON. Verify that the oil pressure warning light illuminates.

Submit a Product Program Claim with the information indicated below.

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

General Motors will notify customers of this program on their vehicle (see copy of customer letter included with this bulletin).

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

Dealers are to service all vehicles subject to this program 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. Program 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 program enters your vehicle inventory, or is in your dealership for service in the future, you must take the steps necessary to be sure the program correction has been made before selling or releasing the vehicle.

Dear Commercial Truck Customer:

This notice is sent to inform you that General Motors is conducting a customer satisfaction program that affects certain 2003 and 2004 model year Chevrolet and GMC W3500 and 4500 Series vehicles, and Isuzu NPR and NPR-HD vehicles equipped with a 6.0L gas engine.

We have learned that your vehicle may have been built with an insufficient ground to the oil pressure switch. This condition can prevent the engine oil pressure warning light from illuminating when the vehicle is started and when the engine oil pressure falls below normal during vehicle operation.

To prevent this condition from occurring, your dealer will install an oil cooler ground harness. This service will be performed for you at no charge .

We recommend that you contact your dealer to arrange a service date.

Presenting the enclosed form to your dealer will assist in making the necessary correction in the shortest possible time.

If you no longer own this vehicle, please check the appropriate box and provide new owner information, if available.

If you have any questions or need any assistance, just contact your dealer or the appropriate Customer Assistance Center between the hours of 8:00 AM and 11:00 PM EST, Monday through Friday. Their number is 1-800-862-4389.

We sincerely regret any inconvenience or concern this situation may cause you. We want you to know that we will continue to do our best, throughout your ownership experience, to ensure that your commercial truck provides you many miles of enjoyable driving.

General Motors Corporation

Enclosure

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