2000 Chevrolet W3500

THE PRELIMINARY EVAULATION IS BEING UPGRADED.DURING THE EA ODI WILL LIMITITS INVESTIGATION TO ONLY THOSE VEHICLES EQUIPPED WITH A HYDRO-BOOST SYSTEM, WHICH PROVIDES POWER ASSIST TO THE BRAKING AND STEERING SYTEMS.VACCUUM BRAKE BOOSTER VEHICLES ARE EXCLUDED.ODI HASEXPANDED THE SCOPE OF THE EA TO INCLUDE MODEL YEARS2003 AND 2004, ASDURING THE PE, ODI LEARNED THAT THE HYDROBOAST PUMPS WERE MODIFIED IN FEBRAURY 2004.THEREFORE,ODI HAS EXPANDED THE SCOPE TO INCLUDE THE ADDITIONAL MODEL YEARS.ODI'S IS CONCERNED BECAUSE THISISA SUDDEN FAILURE THAT AFFECTS TWO CRITICAL SYSTEMS OF THE VEHICLE, BRAKES AND STEERING, AT THE SAME TIME.THE ABILITY OF THE OPERATOR TO HANDLE THE DUAL FAILURES IS A CONCERN. FURTHER, THESE VEHICLES TEND TO BE WORK VEHICLES, WITH SOME OVER 10,000 POUNDS GVWR AND MANY EQUIPPED TO PULL LARGE TRAILERS.DUAL FAILURES OF HEAVILY LOADED VEHICLES AND VEHICLES PULLING TRAILERS FURTHER INCREASES THE SAFETY RISK.ODI PLANS TO CONDUCT TESTING TO QUANTIFY THE BRAKING AND STEERING PERFORMANCE DEGRADATION AND THE IMPACT ON SAFE VEHICLE CONTROL, WHEN A HYDROBOAST PUMP FAILS.

Vehicle Wide Programming (VWP) is a new process to update software on GM Vehicles. It provides the ability via a single selection within Techline Connect to first identify which modules need updating and then proceed to updating affected modules (with some exceptions). The updating of modules is completed in parallel instead of the technician needing to update one module at a time. This allows a more streamlined approach for dealers and customers.

GM is receiving damaged (cracked or broken) transmission cores returned to the reman facilities. The damage is being caused either in the removal process by the technician, or inadequate packaging or shipping. This bulletin advises the dealers to be more careful not to damage the transmissions during removal and to package the core properly for return.

This service bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.

This bulletin provides information for use on a Product Assistance Claim (PAC), which is formerly known as a Product Allegation Resolution (PAR) claim.

This technical bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.

This service bulletin provides service information to technicians on guidelines to replace Oil Cooler, Oil Cooler Lines and Oil Tank if the engine was replaced where large amounts of debris has flowed throughout the oiling system.