Thanks for the join. Just bought a 2003 C3500 Duramax three weeks ago. Smokes a little while Idling but not bad. One week ago a injector cup went bad, started dumping water on the #6 piston. Just about got it back together now. All cups redone with one replaced and all injectors rebuilt. Not bad for around $500 doing it myself. Better than the $3000 everybody wanted to do it.