One problem related to tank mounting has been reported for the 2008 Ford F-150. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Ford F-150 based on all problems reported for the 2008 F-150.
Smelled odor of gasoline while driving. Drove approximately 3 miles and when exited vehicle, strong odor of gasoline. Walked to rear of vehicle and saw a trail of gasoline splatters behind 2008 Ford f150. Looked under vehicle and saw a pool of gasoline with gasoline dripping from all around fuel tank and surrounding area. Immediately got assistance and determined that gasoline was coming from area at top of fuel tank-area of fuel pump (by turning key on a 1-2 seconds while assistant watched under pickup). We removed the fuse to fuel pump relay and towed vehicle (100 ft) to area where we could wash gasoline off with water hose and pushed vehicle into shop and removed pickup bed to get a visual at leak area. Vent hose to filler cap was broken at top of tank (this is not a hose that normally has gasoline or pressure. Reinstalled fuse and rapidly turned key on and off with 2 persons watching. A huge amount of gasoline was sprayed out when the pump was energized. When assistant touched the hose at source of leakage to pull hose off, the plastic connection on the pump broke off (no force was applied). Called Ford dealer and were informed it was under warranty--informed them of observations and action we took. When Ford got the vehicle they basically said this was an owner abuse and was not a defect. Vehicle has not been subject to any rough treatment. If I had driven this vehicle enough to get exhaust hot or had any source of ignition the vehicle would have basically exploded and burned, it probably lost 5-6 gallon of gas in 3 miles(5 minutes). There was a split in plastic connection that broke off and appearance of other cracks in area. In most cases the first evidence of a problem would be when the vehicle ignited. Enough gasoline dripped off tank area on asphalt to Mar area. Ford dealer has vehicle and parts, indicated it would be 4-10 days to get replacement parts. This has serious fire potential and I have no explanation for break except defective.