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.
•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.
•Cold inflation pressure:The tire pressure when the vehicle has
been stationary and out of direct sunlight for an hour or more and
prior to the vehicle being driven for 1 mile (1.6 km).
•Recommended inflation pressure:The cold inflation pressure found
on the Safety Compliance Certification Label located on the B-Pillar or
the edge of the driver’s door.
•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.
INSPECTING AND INFLATING YOUR TIRES
Safe operation of your vehicle requires that your tires are properly
inflated. Remember that a tire can lose up to half of its air pressure
without appearing flat.
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Every day before you drive, check
your tires. If one looks lower than
the others, use a tire gauge to check
pressure of all tires and adjust if
required.
At least once a month and before
long trips, inspect each tire and
check the tire pressure with a tire
gauge (including spare, if equipped).
Inflate all tires to the inflation
pressure recommended by Ford
Motor Company.
Inspecting your tires
Periodically inspect the tire treads for uneven or excessive wear and
remove stones, nails, glass or other objects that may be wedged in the
tread grooves. Check for holes or cuts that may permit air leakage from
the tire and make necessary repairs.
Also inspect the tire sidewalls for cuts, bruises and other damage. If
internal damage to the tire is suspected, have the tire demounted and
inspected in case it needs to be repaired or replaced. For your safety,
tires that are damaged should not be used because they are more likely
to blow out or fail. Tires can be damaged during off-road use, so
inspection after off-road use is also recommended.
Inflating your tires
Use a tire gauge to check the tire inflation pressure, including the spare
(if equipped), at least monthly and before long trips. You are strongly
urged to buy a reliable tire pressure gauge, as automatic service station
gauges may be inaccurate. Ford recommends the use of a digital or dial
type tire pressure gauge rather than a stick type tire pressure gauge.
Use the recommended cold inflation pressure for optimum tire
performance and wear. Under-inflation or over-inflation may cause
uneven treadwear patterns.
Under-inflation is the most common cause of tire failures and
may result in severe tire cracking, tread separation orblowout,
with unexpected loss of vehicle control and increased risk of injury.
Under-inflation increases sidewall flexing and rolling resistance,
resulting in heat buildup and internal damage to the tire. It also may
result in unnecessary tire stress, irregular wear, loss of vehicle control
and accidents. A tire can lose up to half of its air pressure and not
appear to be flat!
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Always inflate your tires to the Ford recommended inflation pressure
even if it is less than the maximum inflation pressure information found
on the tire. The Ford recommended tire inflation pressure is found on
the Safety Compliance Certification Label which is located on the B-Pillar
or the edge of the driver’s door. Failure to follow the tire pressure
recommendations can cause uneven treadwear patterns and adversely
affect the way your vehicle handles.
Maximum Permissible Inflation Pressureis the tire manufactures’
maximum permissible pressure and/or the pressure at which the
maximum load can be carried by the tire. This pressure is normally
higher than the manufacturer’s recommended cold inflation pressure
which can be found on the Safety Compliance Certification Label which
is located on the B-Pillar or the edge of the driver’s door. The cold
inflation pressure should never be set lower than the recommended
pressure on the Safety Compliance Certification Label.
When weather temperature changes occur, tire inflation pressures also
change. A 10° F (6° C) temperature drop can cause a corresponding
drop of 1 psi (7 kPa) in inflation pressure. Check your tire pressures
frequently and adjust them to the proper pressure which can be found
on the Safety Compliance Certification Label.
If you are checking tire pressure when the tire is hot, (i.e. driven more
than 1 mile [1.6 km]), never “bleed” or reduce air pressure. The tires are
hot from driving and it is normal for pressures to increase above
recommended cold pressures. A hot tire at or below recommended cold
inflation pressure could be significantly under-inflated.
To check the pressure in your tire(s):
1. Make sure the tires are cool, meaning they are not hot from driving
even a mile.
Note:If you have to drive a distance to get air for your tire(s), check
and record the tire pressure first and add the appropriate air pressure
when you get to the pump. It is normal for tires to heat up and the air
pressure inside to go up as you drive. Never “bleed” or reduce air
pressure when tires are hot.
2. Remove the cap from the valve on one tire, then firmly press the tire
gauge onto the valve and measure the pressure.
3. Add enough air to reach the recommended air pressure
Note:If you overfill the tire, release air by pushing on the metal stem in
the center of the valve. Then recheck the pressure with your tire gauge.
4. Replace the valve cap.
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5. Repeat this procedure for each tire, including the spare.
Note:Some spare tires operate at a higher inflation pressure than the
other tires. For T-type/mini-spare tires (seeT-Type/Mini-Spare Tire
Informationsection for description): Store and maintain at 60psi (4.15
bars). For Full Size and Dissimilar spare tires (seeDissimilar Spare
Tire/Wheel Informationsection for description): Store and maintain at
the higher of the front and rear inflation pressure as shown on the Safety
Compliance Certification Label.
6. Visually inspect the tires to make sure there are no nails or other
objects embedded that could poke a hole in the tire and cause an air
leak.
7. Check the sidewalls to make sure there are no gouges, cuts or bulges.
TIRE REPLACEMENT REQUIREMENTS
Your vehicle is equipped with tires designed to provide a safe ride and
handling capability.
Only use replacement tires and wheels that are the same size
and type (such as P-metric versus LT-metric or all-season versus
all-terrain) as those originally provided by Ford Motor Company. Use of
any tire or wheel not recommended by Ford Motor Company can affect
the safety and performance of your vehicle, which could result in an
increased risk of loss of vehicle control, vehicle rollover, personal injury
and death. Additionally the use of non-recommended tires and wheels
could cause steering, suspension, axle or transfer case/power transfer
unit failure. If you have questions regarding tire replacement, see an
authorized dealer.
Make sure all tires and wheels on the vehicle are of the same size, type,
tread design, brand, load-carrying capacity and speed rating because it
can affect the safety and performance of your vehicle, which could result
in an increased risk of loss of vehicle control, vehicle rollover, personal
injury and death.
The tire pressure monitoring sensors mounted in the wheels (originally
installed on your vehicle) are not designed to be used in after-market
wheels.
The installation of replacement tires with steel cord body plies in the tire
sidewall may cause malfunction of the Tire Pressure Monitoring System
(TPMS), and is not recommended (cord material information is molded
on the tire sidewall). Additionally, if your vehicle was originally equipped
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with run-flat tires, replacing them with tires that are not identical to
those originally fitted may cause malfunction of the TPMS, and is not
recommended. Run-flat tires should not be used to replace regular tires.
Always check your TPMS indicator immediately after replacing one or
more tires on your vehicle. If the TPMS indicator is on, your TPMS is
malfunctioning. Your replacement tire might be incompatible with your
TPMS system, or some component of the TPMS system may be damaged.
Important:Remember to replace the spare tire when you replace the
road tires on your vehicle. Even if it has never been used, the spare tire
should be replaced because tires degrade over time.
Important:Remember to replace the wheel air valves when the road
tires are replaced on your vehicle.
INFORMATION CONTAINED ON THE TIRE SIDEWALL
Federal law requires 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.
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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.
Letter rating Speed rating - mph (km/h)
M 81 mph (130 km/h)
N 87 mph (140 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)
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Letter rating Speed rating - mph (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.
8.U.S. DOT Tire Identification Number (TIN):This begins with the
letters “DOT” and indicates that the tire meets all federal standards. The
next two numbers or letters are the plant code designating where it was
manufactured, the next two are the tire size code and the last four
numbers represent the week and year the tire was built. For example,
the numbers 317 mean the 31st week of 1997. After 2000 the numbers
go to four digits. For example, 2501 means the 25th week of 2001. The
numbers in between are identification codes used for traceability. This
information is used to contact customers if a tire defect requires a recall.
9.M+S or M/S:Mud and Snow, or
AT:All Terrain, or
AS:All Season.
10.Tire Ply Composition and Material Used:Indicates the number of
plies or the number of layers of rubber-coated fabric in the tire tread and
sidewall. Tire manufacturers also must indicate the ply materials in the
tire and the sidewall, which include steel, nylon, polyester, and others.
11.Maximum Load:Indicates the maximum load in kilograms and
pounds that can be carried by the tire. Refer to the Safety Compliance
Certification Label, which is located on the B-Pillar or the edge of the
driver’s door, for the correct tire pressure for your vehicle.
12.Treadwear, Traction and Temperature Grades
•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.
•Traction: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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•Temperature: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.
13.Maximum Permissible Inflation Pressure:Indicates the tire
manufacturers’ maximum permissible pressure and/or the pressure at
which the maximum load can be carried by the tire. This pressure is
normally higher than the manufacturer’s recommended cold inflation
pressure which can be found on the Safety Compliance Certification
Label which is located on the B-Pillar or the edge of the driver’s door.
The cold inflation pressure should never be set lower than the
recommended pressure on the vehicle label.
The tire suppliers may have additional markings, notes or warnings such
as standard load, radial tubeless, etc.
Additional information contained on the tire sidewall for “LT” type
tires
“LT” type tires have some additional
information beyond those of “P”
type tires; these differences are
described below:
1.LT:Indicates a tire, designated by
the Tire and Rim Association
(T&RA), that is intended for service
on light trucks.
2.Load Range/Load Inflation
Limits:Indicates the tire’s
load-carrying capabilities and its
inflation limits.
3.Maximum Load Dual lb. (kg)
at psi (kPa) cold:Indicates the
maximum load and tire pressure
when the tire is used as a dual; defined as four tires on the rear axle (a
total of six or more tires on the vehicle).
4.Maximum Load Single lb. (kg) at psi (kPa) cold:Indicates the
maximum load and tire pressure when the tire is used as a single;
defined as two tires (total) on the rear axle.
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