I would run used in the rear for off-road only (for rock crawling, not desert racing and the like) but not on the street. Front really doesn't matter much, so sure. But it's too hard to get a good setup when they are already worn in. Doubt you would ever match them again. We (well, Brian) had a heck of a time getting my front 4.56s resetup on my Detroit and I would hate to run that on the street in the rear...