INFO. ON NEW EXTENDED LIFE ENGINE COOLANT. GMC Truck GMC MD P Bus Chassis 1995

SUBJECT: INFORMATION ON NEW EXTENDED LIFE ENGINE COOLANT KNOWN AS DEX-COOL(TM)

MODELS: 1995 PASSENGER CARS AND TRUCKS

A NEW EXTENDED LIFE ENGINE COOLANT KNOWN AS "DEX-COOL(TM)" WILL BE USED IN ALL GENERAL MOTORS VEHICLES. SOME TRUCKS WILL BE FILLED WITH DEX-COOL(TM) BEGINNING IN LATE MAY; MOST VEHICLES WILL CONVERT IN JULY, 1995 WITH THE REMAINING VEHICLES TO CONVERT BY JANUARY, 1996. MOST OF THESE VEHICLES WILL BE 1995 MODELS. ALL PRODUCTION FOR 1996 MODELS WILL UTILIZE DEX-COOL(TM). IT IS IMPERATIVE TO NOTE THE FOLLOWING ABOUT DEX-COOL(TM) ENGINE COOLANT:

- **IT IS ORANGE IN COLOR TO DISTINGUISH IT FROM CONVENTIONAL COOLANT.**

- **THE SERVICE CHANGE INTERVAL ON VEHICLES WHICH ARE BUILT WITH DEX-COOL(TM) IS 5 YEARS/100,000 MILES, WHICHEVER OCCURS FIRST.**

- **TO MAINTAIN FULL CORROSION PROTECTION DURABILITY, DEX-COOL(TM) MUST NOT BE MIXED WITH CONVENTIONAL (CONTAINING SILICATE) ENGINE COOLANTS.**

- **DEX-COOL(TM) IS AN ETHYLENE GYLCOL BASED PRODUCT, THEREFORE, BOIL AND FREEZE PROTECTION ARE MEASURED IN THE SAME FASHION AS CONVENTIONAL COOLANTS.**

**TO FULLY REALIZE ITS MANY ADVANTAGES, DEX-COOL(TM) MUST NEVER BE MIXED WITH CONVENTIONAL COOLANTS**.

IT IS PARTICULARLY IMPORTANT TO TOP-OFF NEW VEHICLES WITH DEX-COOL(TM). DEX-COOL(TM) FORMS A PROTECTIVE FILM ON ALUMINUM SURFACES, HOWEVER, IF A VEHICLE WITH LESS THAN 3,000 MILES IS TOPPED-OFF WITH CONVENTIONAL COOLANT, ALUMINUM CORROSION MAY OCCUR.

**DEX-COOL(TM) CAN BECOME CONTAMINATED BY INADVERTENTLY TOPPING-OFF WITH CONVENTIONAL COOLANT, ADDING CONVENTIONAL COOLANT TO THE RADIATOR, OR EVEN IF FILL/DRAIN CONTAINERS ARE SHARED BETWEEN COOLANTS.**

IF CONTAMINATION OCCURS ON A NEW VEHICLE (I.E. DURING VEHICLE PREP), THE COOLING SYSTEM MUST BE IMMEDIATELY DRAINED AND REFILLED WITH DEX-COOL(TM). IF CONTAMINATION WITH CONVENTIONAL COOLANT OCCURS AFTER THE VEHICLE HAS BEEN DRIVEN FOR AT LEAST 3,000 MILES, NO SHORT-TERM PROBLEMS WILL OCCUR; HOWEVER, THE SERVICE CHANGE INTERVAL WILL BE REDUCED FROM 5 YEARS/100,000 MILES TO 2 YEARS/30,000 MILES. MORE INFORMATION ON DEX-COOL(TM) ENGINE COOLANT SERVICE PROCEDURES CAN BE FOUND IN THE 1996 SERVICE MANUALS AND A VIDEO TAPE WHICH WILL BE ISSUED BY STG.

VEHICLES WHICH CONTAIN DEX-COOL(TM) CAN BE IDENTIFIED BY A SPECIAL UNDERHOOD LABEL WHICH STATES "USE DEX-COOL(TM) COOLANT ONLY. . . MEETING SPEC. 6277M". THEY MAY ALSO BE IDENTIFIED BY THE COOLANT'S ORANGE COLOR AND THE INFORMATION CONTAINED IN THE OWNER'S MANUAL.

REGARDING COOLANT RECYCLING:

ENGINE COOLANT RECYCLING IS AFFECTED BY DEX-COOL(TM) AS FOLLOWS. USED DEX-COOL(TM) CAN BE MIXED INTO YOUR "USED" CONVENTIONAL COOLANT STORAGE VESSEL AND THE MIXTURE RECYCLED IN THE SAME MANNER AS YOU ARE ACCUSTOMED TO. THIS RECYCLED MIXTURE OF CONVENTIONAL AND DEX-COOL(TM) COOLANT MUST BE USED AS A 2 YEAR/30,000 MILE CONVENTIONAL COOLANT AND SHOULD NOT BE USED IN VEHICLES ORIGINALLY EQUIPPED WITH DEX-COOL(TM). WHEN SERVICING VEHICLES ORIGINALLY EQUIPPED WITH DEX-COOL(TM), USE ONLY GOODWRENCH-DEX-COOL(TM). ADDITIONAL RESEARCH WILL BE CONDUCTED TO EVALUATE THE FEASIBILITY OF RECYCLING DEX-COOL(TM) TO DEX-COOL(TM) IN THE NEAR FUTURE.

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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.