well we have a 1994 5.7 and when we first got it it ran great, got it licensed drove it a bit and not it smokes more that my cousnins cummins. but it is white smoke, its really bad it has the normal start up smoke but it comes out of that then if it idles for a min or 2 it stats smoking like a freight train. its not valve guide seals because we talked to the guy that we bought it off of and he put new ones in it like 6 weeks befire we bought it. the only thing is he say he never drove it enough to notice it. i think it needs re-ringed but not sure i was hoping you guys could help me. sorry for the novel