2005 6.0 liter fuel tank leak - Diesel Forum

wogdiml · 08-04-2009, 05:32 PM

On my 2005 F350 crew cab the fuel tank developed a leak at the front end, leaks down the sides to the skid plate and drips from there. This just happened after I fueled up and really topped it off slowly the last 4 gallons. I was also parked backward in my driveway so the truck was pointing downhill slightly. Once I turned the truck around, pointed back uphill, the leak stopped and everything is almost dried out after dripping on the driveway a few hours last night. The leak looks like it comes out of the top of the tank, but it is in a spot that is hidden behind the frame right underneath the bed. It is at the opposite end of the tank from the fill tube. What is at the front end of the fuel tanks at the top that could have developed a leak. Any thoughts to fix other than not filling the tank so full (which I've done the past couple of years to haul a travel trailer - to get the extra few gallons in - no leaks before). Ford is going to look on Thursday at it.

SRB · 08-05-2009, 12:00 AM

If memory serves me right ( it's been 4 years since I swapped my tank out of my 05 ) there are 2 rollover vents on top of the tank. One in front and one in the rear section. They have a hose on them that runs over to the frame. Should be able to see them with a mirror and flashlight. Sounds like a bad vent, or the rubber gasket that seals it to the tank.

69cj · 08-05-2009, 09:40 AM

If you overfill the tank it will leak out of the vent. I have to work at it but it has happened to me twice with the truck at the right angle and me trying to get the last ounce to top it off. I don't think you have a problem.

wogdiml · 08-11-2009, 12:47 PM

UPDATE -
As mentioned by 69cj the Ford mechanic said everything checked out. They said it was probably from a combination of 1) overfilled tank 2) parked at a downhill angle 3) 100+ degree day expanded fuel in an already full tank. They think all factors above led to leaking fuel out of the front tank vent. I don't know anything more to argue. I know I put an extra 3-4 gallons of diesel in the tank after the first click. The mechanic emphasized that the first click at the pump means full tank. I have not had any more leaks but have also parked the truck pointing uphill ever since. Kind of stinks to pay Ford $50 to tell me nothing is wrong.