I lost count....
First off my speedo is off cause of the new tires, so it looks like I travel less than I really do cause I haven't calibrated it yet! So know way for any body to really know what they get with 35's. I just go till 1/4 tank and hit up a Costsco cause there gas is always so tastefully cheap. Yummy! All I know is that its not as good as having stock tires on it! Also, learn to love the truck and cruise in it more not thromping the pedal all the time. On the freeway try to keep it on or just above the 2 RPM mark the sweet spot for the freeway you will be getting the best gas mileage.