2008 FORD SUPER DUTY inflation pressure

government test course. For example, a tire graded 150 would wear one
and one-half (112) 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.
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.
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•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. Also referred
to as DOT code.
•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 Tire Label or 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.
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.
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.
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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.
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!
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 or Tire 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 manufacturer’s
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 or Tire
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 or
Tire 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 or the Tire Label.
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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.
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.
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.
2. Remove the cap from the valve on one tire, then firmly press the tire
gauge onto the valve and measure the pressure with the tire gauge.
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.
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 (seeDissimilar Spare
Tire/Wheel Informationsection for description): Store and maintain at
60 psi (4.15 bars). For Dissimilar spare tires and Full-size matching spare
tires (see theDissimilar Spare Tire/Wheel InformationandFull-size
Matching Spare Tire/Wheel Informationsections for descriptions):
Store and maintain at the higher of the front and rear inflation pressure
as shown on the or Safety Compliance Certification Label or the Tire
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.
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Tire inflation information
All tires with Steel Carcass Plies (if equipped):
This type of tire utilizes steel cords in the sidewalls. As such, they
cannot be treated like normal light truck tires. Tire service, including
adjusting the air pressure, must be performed by personnel trained,
supervised and equipped according to Federal Occupational Safety and
Health Administration (OSHA) regulations. For example, during any
procedure involving tire inflation, the technician or individual must
utilize a remote inflation device, and ensure that all persons are clear of
the trajectory area.
WARNINGAn inflated tire and rim can be very dangerous if
improperly used, serviced or maintained. To avoid serious injury,
never attempt to re-inflate a tire which has been run flat or seriously
under-inflated without first removing the tire from the wheel assembly
for inspection. Do not attempt to add air to tires or replace tires or
wheels without first taking precautions to protect persons and
property.
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Improper or inadequate vehicle maintenance can cause tires to wear
abnormally. Inspect all your tires, including the spare, frequently, and
replace them if one or more of the following conditions exist:
Tire wear
When the tread is worn down to
1/16th of an inch (2 mm), tires must
be replaced to help prevent your
vehicle from skidding and
hydroplaning. Built-in treadwear
indicators, or “wear bars”, which
look like narrow strips of smooth
rubber across the tread will appear
on the tire when the tread is worn
down to 1/16th of an inch (2 mm).
When the tire tread wears down to
the same height as these “wear bars”, the tire is worn out and must be
replaced.
Damage
Periodically inspect the tire treads and sidewalls for damage (such as
bulges in the tread or sidewalls, cracks in the tread groove and
separation in the tread or sidewall). If damage is observed or suspected
have the tire inspected by a tire professional. Tires can be damaged
during off-road use, so inspection after off-road use is also
recommended.
Age
Tires degrade over time depending on many factors such as
weather, storage conditions, and conditions of use (load, speed,
inflation pressure, etc.) the tires experience throughout their lives.
In general, tires should be replaced after 6 years regardless of tread
wear. However, heat caused by hot climates or frequent high loading
conditions can accelerate the aging process and may require tires to be
replaced more frequently.
You should replace your spare tire when you replace the road tires or
after 6 years due to aging even if it has not been used.
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•Rear Wheel Drive (RWD)
vehicles/Four Wheel Drive (4WD)
(front tires at top of diagram)
Sometimes irregular tire wear can be corrected by rotating the tires.
Note:If your tires show uneven wear ask your authorized dealer to
check for and correct any wheel misalignment, tire imbalance or
mechanical problem involved before tire rotation.
Note:Your vehicle may be equipped with a dissimilar spare tire/wheel. A
dissimilar spare tire/wheel is defined as a spare tire and/or wheel that is
different in brand, size or appearance from the road tires and wheels. If
you have a dissimilar spare tire/wheel it is intended for temporary use
only and should not be used in a tire rotation.
Note:After having your tires rotated, inflation pressure must be checked
and adjusted to the vehicle requirements.
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•DRW – Six tire rotation
If your vehicle is equipped with dual
rear wheels it is recommended that
the front and rear tires (in pairs) be
rotated only side to side. We do not
recommend splitting up the dual
rear wheels. Rotate them side to
side as a set/pair. After tire rotation,
inflation pressures must be adjusted
for the tires new positions in
accordance with vehicle
requirements.
Sometimes irregular tire wear can be corrected by rotating the tires.
Note:If your tires show uneven wear ask your authorized dealer to
check for and correct any wheel misalignment, tire imbalance or
mechanical problem involved before tire rotation.
Note:Your vehicle may be equipped with a dissimilar spare tire/wheel. A
dissimilar spare tire/wheel is defined as a spare tire and/or wheel that is
different in brand, size or appearance from the road tires and wheels. If
you have a dissimilar spare tire/wheel it is intended for temporary use
only and should not be used in a tire rotation.
Note:After having your tires rotated, inflation pressure must be checked
and adjusted to the vehicle requirements.
INFORMATION CONTAINED ON THE TIRE SIDEWALL
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.
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