18" factory rim.
I've researched for a few hours now. I've seen all kinds of answers.
Company that the leveling kit came from says it will allow up to a 35" inch tire. I just dont know if that is on factory rim offset.
This is probably just as big an issue as the diameter. With the factory rims I would guess you might be limited on the width just a little bit more than a lot of aftermarket rims. I may have to figure this out myself before too long. I'm looking at Ford and Ram 3/4 tons and I want bigger tires than factory but prefer the factory rims.