If you don't do an air intake, be careful with the stock air box. They don't seal properly and need a coat of grease run around the lip on the filter. Dodge is aware of it but isn't doing anything about it. Blaming dusted engines on owners due to lack of service, etc. Mine dusted at 20k with oem filters and the dealership checking them at each oil change. I saw 2 others in dealership dusted needing motors and dodge wouldn't warranty. Decided to get rid of mine and buy '07 5.9 before problems surfaced with higher mileage. Didn't want to look at rings, valves, etc. out of my pocket. Best fuel mileage of any truck I owned though. Guess dust broke everything in. Sorry for the long post, but everyone needs to be aware of this problem.