GM Service Manual Online
For 1990-2009 cars only

CAMPAIGN:PCV VALVE FREEZE-UP (ALASKA ONLY)

SUBJECT: PCV VALVE SYSTEM HOSES FREEZE-UP

Models: 1992-94 Chevrolet/GMC S/T Trucks and M/L Vans with 4.3L Engines

TO: ALL GENERAL MOTORS DEALERS

General Motors of Canada Limited has determined that certain 1992-94 Chevrolet/GMC S/T Trucks and Astro/Safari Vans equipped with 4.3L engines (RPO L35) may experience a condition, if operated below -30 degrees Celsius (-22 degrees Fahrenheit), in which the positive crankcase ventilation (PCV) system hoses freeze-up. This condition can cause engine oil leaks through the dipstick tube and/or rear main seal. Engine failure may result if the vehicle is driven with this condition.

To prevent this condition from occurring, dealers are to replace the PCV valve with a valve calibrated for a higher flow rate. Also, an information sticker is being sent to owners for insertion in their Owner's Manual. This sticker corrects the PCV valve part number so that the proper valve can be ordered in the future.

VEHICLES INVOLVED:

Involved are certain 1992-94 Chevrolet/GMC S/T Trucks and Astro/Safari Vans equipped with 4.3L engines built within the following VIN breakpoints:

Year Model Plant Plant Code From Through ---- ----- ----- ---------- ---- ------- 1992 Chev. S/T Truck Pontiac West "0" SOP EOP 1992 GMC S/T Truck Pontiac West "0" SOP EOP 1992 Chev. S/T Truck Moraine "2" SOP EOP 1992 GMC S/T Truck Moraine "2" SOP EOP 1992 Chev. S/T Truck Shreveport "8" SOP EOP 1992 GMC S/T Truck Shreveport "8" SOP EOP 1993 Chev. S/T Truck Pontiac West "0" SOP EOP 1993 GMC S/T Truck Pontiac West "0" SOP EOP 1993 Chev. S/T Truck Moraine "2" SOP EOP 1993 GMC S/T Truck Moraine "2" SOP EOP 1993 Chev. S/T Truck Shreveport "8" SOP EOP 1993 GMC S/T Truck Shreveport "8" SOP EOP 1994 Chev. S/T Truck Pontiac West "0" SOP R0101984 1994 GMC S/T Truck Pontiac West "0" SOP R0500572 1994 Chev. S/T Truck Moraine "2" SOP R2107894 1994 GMC S/T Truck Moraine "2" SOP R2502544 1994 Chev. S/T Truck Shreveport "8" SOP R8108651 1994 GMC S/T Truck Shreveport "8" SOP R8501910 1994 Chev. S/T Truck Linden "K" SOP RK103094 1994 GMC S/T Truck Linden "K" SOP RK501073 1992 Chev. M/L Van Baltimore "B" SOP EOP 1992 GMC M/L Van Baltimore "B" SOP EOP 1993 Chev. M/L Van Baltimore "B" SOP EOP 1993 GMC M/L Van Baltimore "B" SOP EOP 1994 Chev. M/L Van Baltimore "B" SOP RB108398 1994 GMC M/L Van Baltimore "B" SOP RB503076

NOTE: PLEASE CHECK DCS SCREEN 45 OR YOUR V.I.N. LISTING BEFORE PERFORMING CAMPAIGN TO ENSURE THAT THE VEHICLE IS AFFECTED. ONLY AFFECTED VIN'S WILL BE PAID.

All affected vehicles have been identified by the VIN listing provided to involved dealers with this bulletin. Any dealer not receiving a listing was not shipped any of the affected vehicles.

DEALER CAMPAIGN RESPONSIBILITY:

All unsold new vehicles in dealer's possession and subject to this campaign MUST be held and inspected/repaired per the Service Procedure of this Campaign Bulletin before owners take possession of these vehicles.

Dealers are to perform this campaign on all involved vehicles at no charge to owners, regardless of kilometers traveled, age of vehicle, or ownership, from this time forward.

Owners of vehicles recently sold from your new vehicle inventory with no owner information indicated on the dealer listing, are to be contacted by the dealer, and arrangements made to make the required correction according to instructions contained in this bulletin. This could be done by mailing to such owners a copy of the owner letter accompanying this bulletin. Campaign follow-up cards should not be used for this purpose, since the owner may not as yet have received the notification letter.

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

CAMPAIGN PROCEDURE

Refer to Section 4 of the Service Policies and Procedures Manual for the detailed procedure on handling Product Campaigns. Dealers are requested to complete the campaign on all transfers as soon as possible.

OWNER NOTIFICATION

All owners of record at the time of campaign release are shown on the attached computer listing and have been notified by first class mail from General Motors (see copy of owner letter included with this bulletin). The listings provided are for campaign activity only and should not be used for any other purpose.

PARTS INFORMATION:

Parts required to complete this campaign should be ordered through regular channels, as follows:

Part Number Description Quantity/Vehicle ----------- ----------- ---------------- 6487532 Valve, PCV (1992-93 Model Vehicles) 1

6487779 Valve, PCV (1994 Model Vehicles) 1

PARTS AND LABOUR CLAIM PROCEDURE:

Credit for the campaign work performed will be paid upon receipt of a properly completed campaign claim card or DCS transmission in accordance with the following:

Repair Code Description Time Allowance ----------- ----------- -------------- 2A Install New PCV Valve - 1992-93 M/L Vans .6

3A Install New PCV Valve - 1994 M/L Vans .6

4A Install New PCV Valve - 1992-93 S/T Trucks .3

5A Install New PCV Valve - 1994 S/T Trucks .3

Time allowance includes 0.1 hour for dealer administrative detail associated with this campaign. Parts credit will be based on dealer net plus 30% for 1992-1993 model vehicles and 40% for 1994 model vehicles to cover parts handling.

SERVICE PROCEDURE:

1. For S/T Trucks, raise hood. For M/L Vans, remove engine cover.

2. Remove PCV valve from valve cover.

3. Remove PCV valve from ventilation hose

4. Install new PCV valve to ventilation hose.

5. Install new PCV valve to valve cover.

6. For S/T Trucks, close hood. For M/L Vans, install engine cover.

7. Install information label (shipped with bulletin for in-stock units). Label is to be inserted in Section 6 of the Owner's Manual on the "Service Replacement Part and Filter Recommendations" page.

8. Install Campaign Identification Label.

INSTALLATION OF CAMPAIGN IDENTIFICATION LABEL

Clean surface of radiator upper mounting panel and apply a Campaign Identification Label. Make sure the correct campaign number is inserted on the label. This will indicate that the campaign has been completed.

Dear General Motors Customer.

General Motors of Canada Limited has determined that certain 1992-94 Chevrolet/GMC S/T Trucks and Astro/Safari Vans equipped with 4.3L engines may experience a condition, if operated below -30 degrees Celsius (-22 degrees Fahrenheit), in which the positive crankcase ventilation (PCV) system hoses freeze-up. This condition can cause engine oil leaks through the dipstick tube and/or rear main seal. Engine failure may result if the vehicle is driven with this condition.

To prevent this condition from occurring, dealers are to replace the PCV valve with a valve calibrated for a higher flow rate.

Also, enclosed is an information sticker for your vehicle's Owner's Manual. This sticker should be installed in Section 6, "Service and Appearance Care," on the page titled "Service Replacement Part and Filter Recommendations." This sticker has a corrected part number and will help to avoid improper PCV usage in the future.

This service will be provided for you at no charge.

Please contact your GM dealer as soon as possible to arrange a service date.

If parts are required, ask your dealer for details regarding their availability. If parts are not in stock, they can be ordered before scheduling your service date.

This letter identifies your vehicle. Presentation of this letter to your dealer will assist their Service personnel in completing the necessary correction to your vehicle in the shortest possible time.

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

Customer Support Department General Motors of Canada Limited

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.