CAMPAIGN: POTENTIAL MACHINING METAL CHIPS IN ENGINE. GMC Truck Jimmy

CUSTOMER SATISFACTION CAMPAIGN

SUBJECT: 96-C-37 - POTENTIAL MACHINING METAL CHIPS IN ENGINE ---------------------------------------------------

MODELS: 1996 BLAZERS/JIMMYS/BRAVADAS EQUIPPED WITH 4.3L ENGINE (L35) BUILT AT MORAINE ASSEMBLY PLANT ------------------------------------------------------

This Bulletin Was Sent Out Via DCS To All Light Duty Dealers On June 21, 1996.

General Motors has decided that certain 1996 Blazer/Jimmy/Bravada model vehicles equipped with 4.3L engine (L35), built at the Moraine Assembly plant, may exhibit a condition in which an excessive amount of metal machining chips in the engine may cause degradation of the main bearings, resulting in bearing failures.

To correct this condition, dealers are to run an engine operation road test to determine whether excessive machining chips exist and replace the engine, if necessary, on vehicles in dealer inventory.

VEHICLES INVOLVED

NOTICE: It is anticipated that approximately five (5) percent of involved units will require enyyine replacement. Please follow the inspection procedure before notifying the Romulus Engine Plant that a replacement engine is required.

Involved are certain 1996 Blazer/Jimmy/Bravada model vehicles equipped with 4.3L engine (L35) and built within the following VIN breakpoints:

PLANT YEAR DIVISION MODEL PLANT CODE FROM THROUGH ---- -------- ----- ----- ----- ---- -------

1996 GMC S/T Moraine "2" T2567772 T2569919 1996 Chevrolet S/T Moraine "2" T2283888 T2289017 1996 Oldsmobile T Moraine "2" T2705580 T2706533

NOTICE: Dealers should confirm vehicle eligibility through VISS (Vehicle Information Service System) or ServiceNet (GMC only) prior to beginning campaign 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 have been prepared and are being furnished to involved dealers with the campaign bulletin. Any dealer not receiving a computer listing with the campaign bulletin has no involved vehicles currently assigned.

PARTS INFORMATION

Part Quantity/ Number Description Vehicle ------ ----------- ---------

N/A 4.3L Engine 1

Engines required for this campaign are to be obtained at no charge directly from the Romulus Engine Plant by calling 1-800-844-1082. Removed engine assemblies are to be returned to the Romulus Engine Plant. Failure to return the concerned engine will result in the dealership being billed the dealer net cost of the exchanged engine. DO NOT ORDER REPLACEMENT ENGINE FROM GMSPO.

NOTICE: It is anticipated that approximately five (5) percent of involved units will require engine replacement. Please follow the inspection procedure before notifying the Romulus Engine Plant that a replacement engine is required.

CUSTOMER NOTIFICATION

Customers who have already taken delivery of an involved unit will not be notified since operating the vehicle completes the testing operation.

DEALER CAMPAIGN RESPONSIBILITY

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

SERVICE PROCEDURE

1. Warm up the engine at idle speed until it reaches normal operating temperature (thermostat opens), approx. 13 minutes (more or less depending on ambient and engine temperature).

2. Manually select the lowest forward gear (1) and drive the vehicle with moderate acceleration until the vehicle shifts into 2nd gear (approx. 32 MPH).

CAUTION:

Always operate the vehicle in a safe manner.

3. Manually select 2nd gear and drive the vehicle for 10 minutes not exceeding 40 MPH.

The intention is to drive the vehicle at approx. 3000 engine RPM, realizing traffic conditions may vary greatly.

4. Park the vehicle, with the hood open and the engine running, listen for any ABNORMAL engine sound such as a bearing chirp, knock or squeal.

Verify that any noise heard is not "whoop noise" or accessory drive related. This campaign does not cover those or any other concerns.

"Whoop noise" occurs after an extended hot idle and is generally not audible above 1500 engine RPM.

5. If the engine is judged to emit no abnormal engine sounds, of the type described in step #4, no further action is required. Go to step #7.

6. If abnormal engine noise (of the type described in step #4 is detected), the engine should be exchanged with a new assembly. Refer to the 1996 S/T Service Manual, Book 1 of 2, Page 6A3-29.

Request an exchange engine by calling 1-800-844-1082.

IMPORTANT: Engines removed must be returned in compliance with standard engine exchange policies.

7. Install the GM Campaign Identification Label.

Engine Return Procedures

The removed engine must be returned to the Romulus Engine Plant immediately (not later than 7 days after the receipt of the replacement unit).

FAILURE TO RETURN THE CONCERNED ENGINE WILL RESULT IN THE DEALERSHIP BEING BILLED THE DEALER NET COST OF THE EXCHANGED ENGINE.

The removed engine must be returned as complete as the replacement engine that was provided in the exchange engine shipping container.

The exchange unit will be shipped with a quantity of oil; check oil level before starting engine.

Included with the exchange unit will be return shipping instructions, including a return shipping label (freight collect at destination) and a partially completed Bill of Lading.

Shipping Preparation

DRAIN ALL FLUIDS FROM THE REMOVED ENGINE AND INSTALL ANY PLUGS TAKEN OFF THE EXCHANGE ENGINE.

Remove the engine assembly as outlined in the applicable service manual. Remove any plastic shipping plugs and covers from the exchange unit and install them on the removed unit.

Recrate the removed engine into the original shipping container. Place a copy of the repair order and the completed identification card in an envelope and attach the envelope to the engine being returned.

Shipping Instructions

Remove the original shipping tag and attach the return shipping label to the container. The Bill of Lading and Custom Papers (Canada only) provided with the exchange engine are the only documents required to return the removed engine.

Important: The carrier, whose name and phone number appear on the Bill of Lading, should be used for the return engine shipment. USE GROUND FREIGHT ONLY!! Please refer to detailed instructions provided in the information packet accompanying the exchange engine.

After the Bill of Lading has been dated and signed by the carrier, retain the last copy with your repair order and provide the other copies to the carrier. Your copy of the Bill of Lading, signed by the carrier, is your proof of returning the engine.

The removed engine is to be shipped by Truck Freight Collect to the Romulus Engine Plant (again, refer to the detailed instructions provided in the information packet accompanying the exchange engine).

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 campaign number and the five (5) digit dealer code of the dealer performing the campaign service. This information may be inserted with a typewriter or a ball point 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 by the customer for periodic servicing. When installing the Campaign Identification Label, be sure to install the clear protective covering. Additional Campaign Identification Labels can be obtained from VISPAC Incorporated by calling 1-800-269-5100 (Monday-Friday, 8:00 a.m. to 4:30 p.m. EST). Ask for Item Number S-1015 when ordering.

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

CLAIM INFORMATION

Submit a Product Campaign Claim with the information indicated below:

REPAIR PART FAILED PARTS LABOR LABOR NET PERFORMED COUNT PART NO. ALLOW CC-FC 0P HOURS ITEM

Inspection Test Only - - - MA-96 V9948 0.6 (A)

a) Inspection and Engine Replacement- - - - MA-96 V9949 7.8 (B) S 2WD w/Auto Trans (includes A/C)

b) Inspection and Engine Replacement - 9.4 T 4WD/All WD w/Auto Trans (includes A/C)

* For Campaign Administrative Allowance, add 0.1 hours to the "Labor Hours". For Engine Exchange Administrative Allowance, add 0.2 hours to the "Labor Hours". Total Administrative Allowance not to exceed 0.3 hours.

** The amount identified in the "Net Item" column should represent (A) the sum of the gasoline needed to perform the required inspection (not to exceed $5.00). and (B) the dealer allowance of $332 for an engine assertibly, based on previously established Formal Engine Exchange Program allowance, miscellaneous items such as engine oil and coolant needed lo top off fluid levels when an engine is replaced as well as gasoline needed to perform the required inspection.

Refer to the General Motors Corporation Claims Processing Manual for details on Product Campaign Claim Submission.

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.