One problem related to fuel injector has been reported for the 2004 Chevrolet 2500. The most recently reported issues are listed below.
I had my fuel injectors replaced in June of 2010 under an extended warranty from gm with no out of pocket cost. 18 months later I am having the same problem, fuel injector failure as diagnosed by a local cheverolet dealer, but being told that I am now out of warranty and it will cost $3500+ to repair. If there is a defect in the injectors, previously covered for 7 years/200,000 miles, why are the "new improved" injectors only coming with 12 months/12,000 miles. Gm has a fuel injector problem with their duramax diesels that need to be addressed. I have read hundreds of post from people with the same problems. And Chevrolet is not offering any help with any of them. I am dealing with gm now, and so far have gotten nowhere with the issue.