After receiving some 300 complaints, the National Highway Traffic Safety Administration (NHTSA) has officially expanded its investigation of 1997-2001 Ford F-150 pickups from 1.4 million trucks to 2.73 million.

The issue is whether or not the straps that hold the fuel tank can corrode and break down, which is a potential fire risk. According to the NHTSA website, “The straps that support the fuel tank can rust and break, possibly dropping the tank and causing a fuel leak. Leaking gasoline presents a fire hazard.”

Overall, there have been two reports of fire breaking out due to leaking fuel. One fire quickly put itself out. The other fire burned and destroyed the vehicle. An investigator found the cause of the fire was that the gas tank fell off the vehicle. No injuries were reported in either case.

According to the The Detroit News, Ford is working with NHTSA and will continue to cooperate with the investigation. An investigation is a necessary step to preclude a recall.

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