superj

i recently got some 31s and used to have 215/75s. can someone who happens to know how to figure the difference in circumference tell me how to figure it? i was getting about 14mpg before and i want to see how much a difference i am getting now.

prior to the new tires, my odometer was dead on what the gps on my phone read on the highway. now, my my phone reads about 3mph higher then what the odometer says at 65.

i have the auto tranny and 3.55 diffs.

i used to get 220 to 240 on a tank.

thanks guys and ladies.