FORD 2004 F-550 v.3 - Manual (Page 271)

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 99 mph (159 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.
Letter rating Speed rating - mph (km/h)
Q 99 mph (159 km/h)
R 106 mph (171 km/h)
S 112 mph (180 km/h)
T 118 mph (190 km/h)
U 124 mph (200 km/h)
H 130 mph (210 km/h)
V 149 mph (240 km/h)
W 168 mph (270 km/h)
Y 186 mph (299 km/h)
Note: For tires with a maximum speed capability over 149 mph (240 km/h),
tire manufacturers sometimes use the letters ZR. For those with a maximum
speed capability over 186 mph (299 km/h), tire manufacturers always use the
letters ZR.
2004 F250/350/450/550 (f23)
Owners Guide (post-2002-fmt)
USA English (fus)
Maintenance and Specifications
271