Mine just has the 60E. Thee 6speed auto is available on some though, Thanks for the welcome back fellas.

 

nothing wrong with the 4.8 in a crew.. it moves! lol.

 

I haven't done a whole lot to my 07 NNBS 4.8, but it moves pretty good. Just modded my stock airbox/filter/Airaid Intake Tube. The stock intake tubes on these new ones are crazy. 3" free flowing exhaust, Wheatley tuning, and a ported TB. The tuning was the biggest thing, although the ported TB seemed to make a noticable difference in the low end power. Which IMO is where the 4.8 needs the help. I would think doing different gears in yours would help a bunch. Mine came with 3.73's.

 

same here did the Air raid mit tube and you can feel it growl now..

 

I got the 08 NNBS crew cab 4x4 and It is a dog and a gas hog. I have an AFE stage2 CAI and a cat back Flow-Pro exhaust, which did make alot of difference with throttle response. I got EFI Live from black bear performance and haven't had a change to do any logging for him to build me a tune yet. I am new to the tuning so I won't have a clue on where to start. I would like to put long tubes and cat delete pipe on for somemore torque, but $$$. We got the truck to pull a trailer, but it will barely pull itself up a hill. I want a Duramax......

 

I dont know about gas hog. i usually get between 19 and 20mpg which is great for a truck esp the way i drive. blackbear will hook you up good and ill prob pick up 1-2 mpg as well as get rid of that dog feeling which may be the torque management kicking in. as far as dog goes also. what gears do you have? your truck prob weighs a good amount more then mine also.

 

I believe it has 342's but not 100%.