Duramax Upgrades???

[quadzilla499]

I just purchased a 2002 GMC Duramax 4door 4X4 with 87K on it. It has an Allison tranny also. I was looking at putting a programmer, cold air intake and a 4" exhaust on it. What brand or combo's do yall recommend. Looking for fuel mileage but also want some major performance. Will very seldom be pulling a trailer.

[Valsport]

Can't go wrong with the big three, banks, bully dog, edge. you can get intakes, tuners and exhausts from banks and bully dog. I installed a bully dog pcm program on my father's '06 lbz and I was pretty impressed.