I only used it for one day because the truck is in the middle of an oil consumption test that still has 1,000 miles left. It did as advertised keeping the vehicle in V8 mode. On side effect that was unexpected was the transmission that has shifted erratically since new was shifting smooth? Coming up to stop sign the truck would act like I still had my foot on the gas. That went away also. Can't wait till I leave the device in permanently. Well worth the money.
Good power and Mpg
I order the hypertech max tunner for my 03 chevy avalanche 2500 with the 8.1 litter, just to get a little bit more power and mpg, and I was surprised with the results I haven't gone to a Dyno but I definitely feel increase in acceleration and my mpg went up 3mpg more witch is great for the price.