Originally Posted by jbell36
24 is impressive, but i would have to see it to believe it...i know my 6.4 will never get anywhere close to that, unfortunately, even tuned...before the tuner i was getting 11.5
what year and engine is your duramax?
your 6.4 can get that. mine can. do a cold air intake, and egr/dpf delete. and buy a tuner that has emissions control and turn off regen. it will give you around 10mpg better.
It has nearly doubled my fuel mileage since I did that and it has a ton more power.