I honestly don't know about wheels. However, consider that some states don't even have safety inspections, and other states have emissions inspections (very good) but only check gasses and equipment, not fluids, so a car with a massive oil leak (that pollutes the environment!) is "OK" and so on. DOT do get involved with lighting, rubber, belts, and so on at least, so that's something. I hope they get involved with wheels too, I find it necessary.