Note, however, that every tire manufacturer specifies an 8.5" rim width as minimum acceptable rim width for a 255/40/17 tire. Will a 255 mount on an 8" rim? Of course. Is it optimal? Clearly not. I know of three people who blew out their sidewalls (of 255's on 8" rims) at club driving events. The 8" rim pinches the sidewall in more than the tire designer intended; I think it's somewhat of a safety issue. As always, YMMV.