2013 Ford F350 Super Duty Super Cab Owner Manual Printing 3 - Page 349

348 Wheels and Tires INFORMATION CONTAINED ON THE TIRE SIDEWALL Both U.S. and Canada Federal regulations require tire manufacturers to place standardized information on the sidewall of all tires. This information identifies and describes the fundamental characteristics of the tire and also provides a U.S. DOT Tire Identification Number for safety standard certification and in case of a recall. Information on P Type Tires P215/65R15 95H is an example of a tire size, load index and speed rating. The definitions of these items are listed below. (Note that the tire size, load index and speed rating for your vehicle may be different from this example.) C D B A E F G H I M J L K A. P: Indicates a tire, designated by the Tire and Rim Association, that may be used for service on cars, sport utility vehicles, minivans and light trucks. Note: If your tire size does not begin with a letter, this may mean it is designated by either the European Tire and Rim Technical Organization or the Japan Tire Manufacturing Association. B. 215: Indicates the nominal width of the tire in millimeters from sidewall edge to sidewall edge. In general, the larger the number, the wider the tire. C. 65: Indicates the aspect ratio which gives the tire's ratio of height to width. D. R: Indicates a radial type tire. E. 15: Indicates the wheel or rim diameter in inches. If you change your wheel size, you will have to purchase new tires to match the new wheel diameter. 2013 F-250/350/450/550 (f23) Owners Guide gf, 3rd Printing, December 2012 USA (fus)