2008 GMC Sierra Fuel System Problems

The contact owns a 2008 GMC Sierra 1500. The contact stated that while the vehicle was parked in the garage, diesel fuel started leaking onto the garage floor. The contact recently purchased the vehicle, inspected the source of the leak, and discovered that the fuel lines were completely rusted. Additionally, the contact stated that after refueling the vehicle, the fuel level lowered to half a tank the following day, creating a hazard. The vehicle was towed to a dealer but had not yet been diagnosed. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 163,000.

TL* THE CONTACT OWNS A 2008 GMC SIERRA 1500. THE CONTACT STATED THAT A MONTH AFTER HAVING THE VEHICLE TOWED TO AN INDEPENDENT MECHANIC TO HAVE THE FUEL PUMP WAS REPLACED, THE CONTACT WAS UNABLE TO START THE VEHICLE. THE CONTACT WAS INFORMED THAT THE FUEL CONTROL MODULE NEED TO BE REPROGRAMMED AND THAT ONLY AN AUTHORIZED DEALER HAD THE NECESSARY EQUIPMENT TO PERFORM THE REPROGRAMMING. THE VEHICLE WAS TAKEN TO MOLYE CHEVROLET LOCATED AT (115 W MAIN ST, HONEOYE FALLS, NY 14472), AND WAS DIAGNOSED AND REPAIRED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE APPROXIMATE FAILURE MILEAGE WAS 168,000.

BEGAN TO SMELL FAINT RAW GAS FUMES AROUND THE VEHICLE IN THE SUMMER. IN THE AUTUMN MONTHS THE RAW GAS ODOR SMELL INTENSIFIED AND WAS VERY STRONG WITH AN OVERCOMING PRESENCE IN THE CABIN WHILE DRIVING. I BROUGHT THE VEHICLE TO MY SHOP FOR DIAGNOSTIC. THE MECHANIC (NON GMC GARAGE) CALLED BACK SEVERAL HOURS LATER AND SAID I HAD BEEN DRIVING A POTENTIALLY DISASTER. HE ASKED ME TO SEE FOR MYSELF. I WAS ABLE TO VIEW THIS FIRST HAND AFTER HE HAD REMOVED THE FUEL TANK FROM THE VEHICLE. THE FUEL PUMP IS MOUNTED INTO A DEEP SUMP ON THE TOP OF THE GAS TANK. THE SUMP WELL IS RATHER DEEP AND COLLECTS MUD, SILT, DEBRIS AND WATER WHILE DRIVING AND THAT COLLECTS AND BUILD UP OVER TIME INTO THE SUMP AND THAT STAYS MOIST AT ALL TIMES. OVER THE COURSE OF 6 YEARS THE FUEL PUMP HOUSING AND MOUNT RING RUSTED, ROTTED OUT AND STARTED LEAKING RAW GAS THAT WAS SPILLING ONTO THE HOT EXHAUST PIPE ALONGSIDE THE FUEL TANK. I DO NOT GO OFF ROAD WITH THE VEHICLE NOR DO I PLOW SNOW WITH IT. THE VEHICLE IS USED PRINCIPALLY IN HIGHWAY DRIVING. A FEW WEEKS LATER I WAS TALKING TO A FRIEND WHO OWNS A 2010 GMC SUBURBAN AND HE HAD THE EXACT SAME PROBLEM. I SUBSEQUENTLY WENT ON LINE, SEARCHED ON GOOGLE, AND DISCOVERED A NUMBER OF OTHER OWNERS THAT HAD THE SAME PROBLEM WITH THEIR VEHICLES. THIS IS A DESIGN FLAW IN WHICH THE TANK IS DESIGNED WITH THE DEEP CIRCULAR DEPRESSION (A PERFECT SUMP CONDITION) FOR THE MOUNTING OF THE FUEL PUMP AND WITH NORMAL ROAD DRIVING (MOST NOTABLY IN THE NORTHEAST OR NORTHWEST WHERE RAIN AND SNOW IS PREVALENT) THE SUMP WILL STAY MOIST WITH MUD AND DEBRIS COLLECTING CAUSING RUST IN THE FUEL PUMP HOUSING/MOUNTING RING. *TR

2008 GMC SIERRA DENALI HAS INTERMITTENT FUEL GAUGE OPERATION. AFTER FILLING UP THE VEHICLE WHILE DRIVING THE FUEL GAUGE NEEDLE WILL DROP FROM FULL TANK INDICATION TO EMPTY TANK INDICATION EVEN THOUGHT THE TANK IS FUEL OF FUEL. THE DEALER HAS REMOVED THE TANK AND REPLACED THE FUEL SENDING UNIT, BUT HAS NOT RESULTED IN A FIX JUST AN EDUCATED GUESS. ALSO IN THE MORNINGS THE VEHICLE EXPERIENCES A VERY LOUD KNOCKING NOISE WHICH WHEN CONFRONTED AT THE DEALER WAS TOLD THAT THIS WAS A NORMAL NOISE. OCCURS EVERYDAY IN THE MORNING AND WHEN LEAVING WORK IN THE AFTERNOON. *TR