Looking for some advice. I own a 1996 F350 Crew Cab dually with the 460/7.5 liter gasoline engine. I purchased the truck about 9 months ago and it has 140,000 miles on the ODO. For the most part it has been a reliable, great running truck. When I purchased it the seller disclosed that the fuel pump for the front tank was weak and it will usually not start when switched to that tank. He told me that his work-around was to fill the rear tank and avoid using the front. What I have found is that the truck seems to transfer fuel from the rear tank to the front. When I first fueled up both tanks read E and I only filled the rear tank. After driving about 80 miles the fuel gauge was around 1/2. When I switched to the front tank it read almost 1/4 tank. This condition has repeated itself every time I fuel up. It seems that gas is somehow transferring from the rear tank to the front. How is this happening? The truck will usually start when switched to the front tank but it hesitates and sputters.

Any input that an owner has had with this type of condition would be appreciated.

 

There is a valve that stops the fuel from doing just that. Its not closing right and thus allowing fuel to pass into the front tank. I would also think that the it would be robbing valueable pressure from the rear tank.