I picked up about a MPG in going from 37's to 35's. It only affects in town driving, though. I got 15-16 on the interstate with both set ups. 13-14 with 37's in town and 14-15 with 35's in town. I have had stock 3.73's the whole time also. I believe that weight has the biggest effect, closely followed by width.
My 37 Toyo wheel and tire combo cleared 100lbs easily. Sure it killed the MPG, but it really killed my back and legs rotating tires.
My 37 Toyo wheel and tire combo cleared 100lbs easily. Sure it killed the MPG, but it really killed my back and legs rotating tires.