You can do a quick check of the fuel pump, by turning the truck on(obviously, w/o the start), adn finding the pressure fitting ont he fuel rail. You can either get a gauge to fit the fitting(at least a 60 psi gauge), OR (at your own risk), push in the stem, adn see if fuel sprays out.. make a note how it comes out, if it is a nice strong spray, try the fuel filter first, and if that doesnt salve it, get an actuall pressure reading, adn then start looking into your injectors(though, I think its a pump my self).. if the flow seems weak, or not at all.... well, your fix is gonna be VERY obvious....

HTH
Chase