Can anyone tell me how far I actually traveled? My speedo hasnt been recalibrated, but stock was 265/75/16, and now I have 315/75/16 tires. So like from 31's to 35's. I went 215 miles on the rear tank, so I'm guessing I probably actually went about 20 miles further than that. I think you just have to figure out how much of a % bigger the tires are, then take that % and add it to the miles driven.