I have not put but maybe 20 miles on it. Been in company car all week . But I can tell you that it is a different truck. With the 8 speed it is not a dog when taking off and the truck has a firm, planted stance when driving. My computer is saying that I avg 14.6 mpg since putting these on. I will be taking it on a little road trip this weekend and will try to report back on mpg's. If I had a do over I would not change a thing so far.