Hey there Jason. While I don't have a diesel myself, yet, lol, from what I've read on here, a couple names that come to mind for diesel programmers are Edge and BullyDog (BullyDog is also a vendor on this site, BTW). Unfortunately, I really can't offer much advice on this subject, but if you check out the diesel specific section, several people have debated this. Here's one thread I found, just to give you a start: http://www.ramforumz.com/showthread.php?t=40904&page=2.
Hope this helps and good luck! If you need any more help, feel free to ask!
hello i live in texas and this is my first diesel.i have an 08 mega cab 2500 w/ the 6.7 and want a programmer but dont want to touch the emission crap due to warranty issues what is the best programmer for power and fuel mileage i can put on and wont mess with the dpf any suggestion.