Hey dascst;
Welcome to the forum, I'm new my self, few days ago. U'll find the site very helpful and interesting at the some times. :? Anyway congrats on the new rig, very nice. I had a new 06' DMAX until 08' when the fuel prices went through the roof ($5.25gal here in CA.). Biggest and dumbest mistake I've ever done traded it, (don't ask please). Anyway I just acquired In Oct. my current truck a 07' Silverado 2500HD 4x2 6.0 Std bed. I'm a happy man again.

As for your MPG remember your far from being broke in yet, as is loosens up you should pick a little not much though. I'm currently right at 12.9MPG and that's pretty much where it locked into. My best to date is 13.1 returning from Reno to Cali.
Did you pick up any MPG after you installed the K&N? I myself haven't done any modes yet except to install a soft tounou cover and stainless steps. My plans are the CAI,TBS, and a 50 series BB Flowmaster muffler.
I miss my DMAX terribly I was getting 14.8MPG right out of the box 15.6 after the Flowmaster install. You can see and hear it on there web site in the street muffler section under the 50 series HD. Anyway keep it touch and enjoy your new rig, I know I am :mrgreen: Rich...