Duramax Lifetime Supporter
Join Date: Feb 2011
Location: Fvcktopia, il
By 300 miles it should b shifting ok. U might b feeling the defuel. On the extreme tune it's quite drastic. Don't try the crazy larry on the DMAX, it doesnt like it. I ran the extreme tune for a long time, even towed with it. It's a good starter programmer. Not sure if it has a relearn like ppe though. Or quick learn whatever it's called. My truck made 400hp and 750lbs ft with a bully dog, CIA, shim kit and exhaust. Ppe was much better than bully dog and efi live is better than sliced bread.
Jeremiah-Red Devil Racing.
-2006 Chevy cc/sb 0% over turbo, 0% over injectors/cp3, 10% over exhaust, 45% over toons.
12.87 @ 105.2
-2011 Harley dyna super glide, Vance & Hines.
-1977 Chevy vega, 6pt roll bar, 5.3/glide and 80mm Ching chong turbo in the works.