'96 F150 starts then sputters and dies

[sunjc1]

I have a 1996 F150 with 5.8L V8. When I got the truck I was told that the front fuel pump was out. When I would fill the back tank it would dump into the front while the truck was running. 2 days ago I was on my way to work with the cruise on and it just started slowing down and lost all power. parked it in a store parking lot and got a ride to work. When I picked it up a few hours later it started right up and ran fine for about 3 miles and did the same thing(without the cruise on). Pulled it into another parking lot and switched to the front tank and it ran fine(before if I switched to the front it would die right away). Ran fine all the way to work another 5 miles. Left work that night and it did the same thing after about 5 miles on the front tank. Now it will start right up but shutter and die on front or back tank. thinking its the switching valve for the tanks since when it started acting up the front tank started working again. Any clues?

[rhandwor]

I think the switching valve is a good place to start checking.