Right now my tires are 235-75-15R. My current stock rim is 15x7J. I was wondering if these tires would fit on 15x8 rims?

Thanks

Most tires in that size will fit up to an 8.5" wheel. 8" should be no problem.

On my old 85 Chevy Scottsdale it came orignally with factory 15x7's and I later bought a set of 15x8 rallye wheels which the 235's on the 7s fit even better on. Not only that the tires looked beefier too.