Ford F-150 2011 Owner's Manual page 239

Tires, Wheels and Loading
Note: If your tire size does not begin with a letter this may mean it is
designated by either ETRTO (European Tire and Rim Technical
Organization) or JATMA (Japan Tire Manufacturing Association).
2. 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.
3. 65: Indicates the aspect ratio which gives the tire's ratio of height to
width.
4. R: Indicates a "radial" type tire.
5. 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.
6. 95: Indicates the tire's load index. It is an index that relates to how
much weight a tire can carry. You may find this information in your
owner's guide. If not, contact a local tire dealer.
Note: You may not find this information on all tires because it is not
required by federal law.
7. H: Indicates the tire's speed rating. The speed rating denotes the
speed at which a tire is designed to be driven for extended periods of
time under a standard condition of load and inflation pressure. The tires
on your vehicle may operate at different conditions for load and inflation
pressure. These speed ratings may need to be adjusted for the difference
in conditions. The ratings range from 81 mph (130 km/h) to 186 mph
(299 km/h). These ratings are listed in the following chart.
Note: You may not find this information on all tires because it is not
required by federal law.
239
2011 F-150 (f12)
Owners Guide, 1st Printing
USA (fus)