I have a weird on going issue that after I get fuel, I go to start the truck and it just cranks and cranks. Then after five or so minutes it starts up.. Im stumped?? Im not sure if the pump is kicking on or not?? I take the fuel pump relay out and put it back it, and that usually is the trick..but other then after I get fuel it always starts right up..

 

The fuel is causing your problem. I know, Duuuh! Now for more: 1. It could be a loose connection of the fuel pump in the tank. Buying fuel moves it enough so it doesn't make contact. Possible, but unlikely.
2. The weight of the fuel causes a part of your vehicle to contact the fuel pump electrical wiring. It may open up the wire - like flipping an off switch to the fuel pump. Moving around in the truck may cause contact of the wires again. The fuel weight may also cause a short circuit in which the fuel pump is involved. I can't tell you exactly how this might occur because there are several possibilities. One would cause the fuel pump fuse to blow. Since you didn't mention that happening, I would eliminate a short from power to ground in the fuel pump circuit and concentrate on a short from one power wire to another. What else is in the fuel pump wiring harness? Look at that and see if there is a problem with anything else within that harness. If so, that is what you need to fix. Hope this isn't too generic to help. Good luck.