i've got a 2003 3500 5.9 with 116000 miles on the clock. a few days a go noticed it was sputtering when i let the clutch out and while giving it gas when already travelling. when i say sputter i mean it miss for a second or two and then will run fine. right after it started doing this i first replaced me fuel filter, one because of the problems and two because it was time at 115000 and that seemed to helped it for a hundred miles or so and now it's doing it still. i should mention that i have no performance mods other than a fass pump which i did to save my injector pump after purchasing the truck. I kinda think it is fuel so filled it up with some stuff from a popular truck stop and put some diesel additive in the tank but those things do not seem to help. thanks