Ford F-150 Heritage (2004 year). Manual — part 53

INFORMATION ABOUT UNIFORM TIRE QUALITY GRADING

New vehicles are fitted with tires
that have a rating on them called
Tire Quality Grades. The Quality
grades can be found where
applicable on the tire sidewall
between tread shoulder and
maximum section width. For
example:

• Treadwear 200 Traction AA Temperature A
These Tire Quality Grades are determined by standards that the United
States Department of Transportation has set.

Tire Quality Grades apply to new pneumatic tires for use on passenger
cars. They do not apply to deep tread, winter-type snow tires,
space-saver or temporary use spare tires, tires with nominal rim
diameters of 10 to 12 inches or limited production tires as defined in
Title 49 Code of Federal Regulations Part 575.104(c)(2).

U.S. Department of Transportation-Tire quality grades: The U.S.
Department of Transportation requires Ford to give you the following
information about tire grades exactly as the government has written it.

Treadwear

The treadwear grade is a comparative rating based on the wear rate of
the tire when tested under controlled conditions on a specified
government test course. For example, a tire graded 150 would wear one
and one-half (1 1/2) times as well on the government course as a tire
graded 100. The relative performance of tires depends upon the actual
conditions of their use, however, and may depart significantly from the
norm due to variations in driving habits, service practices, and
differences in road characteristics and climate.

Traction AA A B C

The traction grades, from highest to lowest are AA, A, B, and C. The
grades represent the tire’s ability to stop on wet pavement as measured
under controlled conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor traction
performance.

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214

The traction grade assigned to this tire is based on
straight-ahead braking traction tests, and does not include

acceleration, cornering, hydroplaning or peak traction characteristics.

Temperature A B C

The temperature grades are A (the highest), B and C, representing the
tire’s resistance to the generation of heat and its ability to dissipate heat
when tested under controlled conditions on a specified indoor laboratory
test wheel. Sustained high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to a level of performance
which all passenger car tires must meet under the Federal Motor Vehicle
Safety Standard No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the minimum required by
law.

The temperature grade for this tire is established for a tire that
is properly inflated and not overloaded. Excessive speed,

underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.

TIRES

Tires are designed to give many thousands of miles of service, but they
must be maintained in order to get the maximum benefit from them.

Glossary of tire terminology
• Tire label: A label showing the OE (Original Equipment) tire sizes,

recommended inflation pressure and the maximum weight the vehicle
can carry.

• Tire Identification Number (TIN): A number on the sidewall of

each tire providing information about the tire brand and
manufacturing plant, tire size and date of manufacture.

• Inflation pressure: A measure of the amount of air in a tire.
• Standard load: A class of P-metric or Metric tires designed to carry a

maximum load at 35 psi [37 psi (2.5 bar) for Metric tires]. Increasing
the inflation pressure beyond this pressure will not increase the tire’s
load carrying capability.

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215

• Extra load: A class of P-metric or Metric tires designed to carry a

heavier maximum load at 41 psi [43 psi (2.9 bar) for Metric tires].
Increasing the inflation pressure beyond this pressure will not increase
the tire’s load carrying capability.

• kPa: Kilopascal, a metric unit of air pressure.
• PSI: Pounds per square inch, a standard unit of air pressure.
• B-pillar: The structural member at the side of the vehicle behind the

front door.

• Bead area of the tire: Area of the tire next to the rim.
• Sidewall of the tire: Area between the bead area and the tread.
• Tread area of the tire: Area of the perimeter of the tire that

contacts the road when mounted on the vehicle.

• Rim: The metal support (wheel) for a tire or a tire and tube assembly

upon which the tire beads are seated.

INFORMATION CONTAINED ON THE TIRE SIDEWALL

Federal law requires tire manufacturer’s 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).

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216

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.

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217