I also own a 2001 Chevy Duramax. Yes I have had injector problems and other things. I have 155,000 miles and the problems started around 100,000. So far Chevy has said that none of the problems were a warranty issue. 3 injectors have failed at different times. When one goes it sounds like you through a rod and major black smoke comes out. Don't panic, the truck will not quit running. I drove mine several miles the the next stop. Chevy told me I could drive it home, but I decided to just tow it. Chevy charged me $1000 to replace the one injector. So I did some research and found that O'Reilly's auto parts sells them for around $300.00 and the gasket kit for $71.00. It is not that bad of a job to change a injector. I am working on coming up with a special tool kit to remove the injectors.
A few other problems to watch out for. Head gaskets , front wheel hubs, and water pump. Good luck and watch secondary fuel filters. They can cause pumps to go out because of lack of flow. Chevy designed the fuel filter to flow at a specific amount. If a better filter is installed it might restrict the flow under load. What I mean is, your engine could be starving for fuel when you step on it. So be careful and just change the filter every 10,000. I have just done some research on this and I am going to start this on my truck.