Need your thoughts on this. My brother and I were talking the other day about the crappy MPG my truck gets (for the record, about 16 MPG driving nice and easy, and low RPM shifts), and we were discussing the possibility that MPG may actually INCREASE by running larger tires such as 33's. The theory being that since Xterra's are geared so low, yet have ample power for their size, so switching to a larger tire would enable you to roll along at a lower RPM to maintain the same speed. The question is: Would the extra weight and rolling resistance of a larger tire negate any potential gains you may achieve with running at the lower RPM???

I am very curious about this; anyone who switched to a larger tire, let me know what your MPG difference was before and after. The only experience I have with this is in my last truck, a 94 4Runner. It was only a 4 cyl, so it got half decent mileage anyways with 31's, but when I switched to 33's my mileage dropped substantially because the 4 banger had to work double time to turn the big tires (ie. 5th gear on the highway was a pipe dream unless you were going downhill in a tailwind.)