Yes, ‘how many revolutions the tire makes in a mile of driving’…. The smaller the differnfece the less the ‘differential’ needs to ‘accomodate’. More difference = heat and abuse.


When you look up a tire on, say, tirerack, for that tire in that size they will list ‘revs per mile’

You match those.

You can also just look at the ‘outer diameter’ of the tire, and match them

You dont ‘build’ a ‘revs/mile’ by choosing the numbers- say 275 and 40 or 265/45… it can be VERY tire specific. A Michelin in a 275/40-20 may have a very different t revs/mile compared to a Pirelli 275/40-20.