problem
 

i have 93 f-150 with 5.0 my problem is i filled the front tank up and my rear tank half full i drove it for awile on the rear tank i returned from my destination and fuel was coming out of my front tank i tighten the cap and it stopped later i went to check on it and thier was fuel still at the top and just pours out when i take the cap off and my gauge reads over full on my front tank what might be my problem

RE: problem
 

you overfilled the tank and due to a pressure change the area that the fuel has taken up has incre3ased and the tank's not big enough to accomodate for it. did you fill up elsewhere? likee... on a mountain or somehting? differnt climate? Extreme Temperature change? As the characteristics of Gas change depending on the enviroment in which you are in. Will become more or less dense.

RE: problem
 

These older ford sometime do not have check valves, so when you run your back tank with a full front tank i will overflow. best suggestion is to get a check valve put on your fuel pump or to run off the front tank, then the back then the front to used what ever flowed into the front tank. I had this problem in my 1990 5.0 but fixed it when i put a new fuel pump in