Tire difference..

[Husker6.5]

That is Old School!

That's because some of us are old people!

 

[Stoney]

Growing old is mandatory... growing up is optional.

 

[THEFERMANATOR]

To answer your question, if your truck had 245/75/16 and you went to 235/85/16, then you need to add roughly 6% to your miles if memory serves me correctly. So if your odometer says you went 100 miles, you've actually gone closer to 106 miles.