I have a friend who has the same truck as i do (well to tell you the truth i have 3 duramax trucks and one old faithful 94 6.5) and he purchased a Gale banks cat back system and i just about fell when i heard how much he paid for it, little over 900.00, oh i'm sure there are some of you who paid alot less but thats what he paid for his and to tell you the truth, mind out pulls his, out runs his and when we hook up the toy haulers to go off roading in the desert, i still out pull him. No theres nothing wrong with his truck, i own a trucking co. and an RV shop, i have a dyno here to tune the semi's and we run a truck or 2 per week, his is running fine however like i said, all i did was run a stock 3" pipe in place of the muffler and that made her run real nice.
Just my thoughts and not trying to change anyone's mind on what to do but i see so many trucks go through my diesel shop with so much stuff on them and ,well from my point of view i love it because theres alway something breaking down and i get to repair there mess ups, however i don't see much problem with the duramax as much as i see with the Power Stroke's and Dodge cummin's that have mods done to them
Thanks for your time
Magoo