I notice a bit of decrease when I go from my winter set(A/T's) to my summer set(M/T's). The M/T's weigh 3 lbs more on aftermarket alloys and both sets are the same size. I lose about 15-20 miles per tank. It could just be the winter gas though too. I have the M/T's on now and the gas is still the winter blend and the per tank miles has decreased so I say its the tires.Goldentaco said:Anyone notice any mpg change when moving from stock tire to more aggressive tire tread design (keeping within same tire size) or vice versa...?