Ford 2010 F-150 Owner's Manual page 233

WARNING: If the tire label shows different tire pressures for
the front and rear tires and the vehicle is equipped with TPMS
(tire pressure monitoring system), then the settings for the TPMS
sensors need to be updated. Always perform the TPMS reset procedure
after tire rotation. If the system is not reset, it may not provide a low
tire pressure warning when necessary. See the TPMS reset procedure
in this chapter.
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.)
1. P: Indicates a tire, designated by
the Tire and Rim Association
(T&RA), that may be used for
service on cars, SUVs, minivans and
light trucks.
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.
2010 F-150 (f12)
Owners Guide, 1st Printing
USA (fus)
Tires, Wheels and Loading
233