Max width tires on stock Rubicon Wheels?
I can't speak for anything larger than the 37x12.5x17 tires I have on mine but I can run 15psi offroad and 30psi on the highway and they do great both ways. As far as "looks" my tires look a little wide for the wheels but they seated very easy and I love the way the factory rims look and the fact that I can replace one for $40 off Craigslist if I kill one. I would hate to suggest you do something that won't work but I wouldn't be afraid to try a 13.5" wide tire.
I had a hard time finding someone to install 35x12.50's on the moab wheels, so I can only imagine something wider. Some places will do it while others wont, its even more difficult finding a good shop to even touch it, mainly for the fact wheel spacers are needed for the 35"s on stock moab wheels.






