You need to remember to re-calculate for larger circumference of the tire. If you don't, you get bad numbers. When you move to a bigger tire you're clocking less miles on the odometer than what you're actually travelling. Plus, they are calculated wrong from factory with the original tire size(205/75/15) clocking more miles than what was actually travelled and displaying a higher speed. I found with the help of a GPS, that a 235/75/15 tire is bang on for speed and distance. I averaged about 27mpg then, and even now with a 31x10.5.
Dave
a couple years ago 30mpg in a tracker was unheard of
you were lucky to be getting 25
weird to see everyones report
you sure you calculating right?
Nah. My '96, 5-sp on stock tires gave me 30mpg day in, day out. 27.x mpg on 29" tires.