Taylor102905

Im havin trouble figuring this code out. The truck can drive fine for days on short trips but as soon as i drive for 2 or more hours the engine starts cuttin out like its havin a loss of fuel. When i press the gas during the fit it tries to die. Ive changed the filter, put a new fps in it and no change. I dont know if its the lift pump or fuel pump or what. Any help is appreciated. Thanks