A lot depends on several factors. One being the rim in question. It is the Premium rim or one of the other OEM offerings? Also, the tire in consideration. Tire makers rate tires different ways. Anticipating Bob's reply, yes I know there is an industry standard, but like most other companies, there is a built in safety net, so recommended rim width may actually be increased as a preventive measure. For example, I believe the published OEM rim width for the Premium rim on my Mustang is 8.00. It measures between 8.50 and 9.00. So, speaking from personal experience, I have a 2003 GT Mustang, Premium Edition and the Cooper Zeon 275/40/17 fit nicely without any problems. No bulging, warping, or change in ride. Furthermore, it has a great tread design and Cooper is a good, old, solid name in the tire industry unlike many now popular tire comapnies flooding the market. Ultimately, the choice, or choices, are yours to make. Good luck and let me know what conclusions you reach.