[ksa8907]

Originally Posted by Baltothewolf

Well, when I went from my 185/65R14 to 165/65R14 I went up 8mpg on the low side, and 15 on the high side. Tires make a huge, huge difference in mileage. Weight and RR I think play the biggest role, more so then actual tire size.

Edit: An example today, round trip going to work, on a good day when I hit all green lights I used get 51mpg max. Today, I got 54.7 and I wasn't even trying, hit most red lights and stopped to get something to eat.

Are you correcting for the size difference? 10.8% reduction in actual miles driven.