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Problems with 1999 GMC Sierra 1500 FUEL SYSTEM, GASOLINE

On average, the 1999 GMC Sierra 1500 starts to “feel” problems with the FUEL SYSTEM, GASOLINE and its various aspects after 184 895 miles.

Recently reported FUEL SYSTEM, GASOLINE problems on 1999 GMC Sierra 1500

Tl* the contact owns a 1999 gmc sierra 1500. the contact stated that while driving 35 mph, he heard an abnormal noise in the drive shaft. the vehicle was taken to an independent mechanic for diagnosis where the contact was informed that the fuel tank straps were fractured. both straps were replaced. the dealer and manufacturer were notified but offered no assistance. the failure and current mileage was 101,000. updated 1/17/13 *cn the consumer stated the rear fuel strap had broken and was rubbing against the drive shaft. the front strap was rusted, but not broken. both were replaced at his expense. updated 01/24/13

I noticed a strong odor of gas coming from under the truck. i only noticed the fuel leaking when the truck was on a downhill grade. i climbed under the truck to see where it was coming from. it turns out that the fuel leak is coming from the return line on the frame under where the fuel filter is attached. that section of the fuel line is totally corroded and fuel is slowly dripping from it. i am taking it to my mechanic tomorrow for repair. the brake line right above the fuel line is also severely corroded. gm really needs to recall and fix these issues due to these corroded fuel and brake lines. i will never buy another gm product again. *tr

Severe corrosion of the brake lines became apparent during a sudden application of the brakes which caused multiple brake lines to rupture and leave the vehicle with no brakes since a line from the master cylinder to the abs unit front left input and the abs to the rear t line blew simultaneously. when removing the damaged brake lines they literally crumbled to pieces due to corrosion. during the repair to the brake lines severe corrosion was noted on the fuel lines also.

The fuel gauge and low fuel warning system on my 1999 gmc sierra pickup has not worked for many months. i have been told by a service facility i trust, that this is a common problem, is costly to fix and most likely will fail again soon. they thought that this should be a recall issue. *nm

The first time i bought the vehicle it overflowed fuel when i filled the fuel tank to it's capacity. i assumed a vent line was loose, but knew it would be a big job to drop the fuel tank and check, so i just limited the amount of fuel i would fill the tank with. on jan 5, 2007, the fuel pump quit working and after dropping the tank no vent line was found to be loose. upon further investigation, i determined the fuel pump mounting flange on the tank was about half connected, thus where the fuel would leak from when the tank was filled to capacity. it appeared the mounting flange is fused on and there was not an adequate bon made. it was on about 1/32" wide for 180 degrees and only about 1/16" wide the other 180 degrees. i have since repaired the tank using a product called jb weld and also installing (4) #10 machines screws with washers and locking nuts holding the flange to the tank. *jb

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