2010 FORD F550 wheel size

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.
WARNING: 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. 139. Grades B and A represent higher levels of
performance on the laboratory test wheel than the minimum required by
law.
WARNING: 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.Tires, Wheels and Loading
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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 Safety Compliance Certification Label or Tire 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. Tires, Wheels and Loading
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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.
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.
WARNING: Under-inflation is the most common cause of tire
failures and may result in severe tire cracking, tread separation
or  blowout  , 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.
Note: Do not reduce tire pressure to change the ride characteristics of
the vehicle. If you do not maintain the inflation pressure at the levels
specified by Ford, your vehicle may experience a condition known as
 shimmy  . Shimmy is a severe vibration and oscillation in the steering
wheel after the vehicle travels over a bump or dip in the road that does
not dampen out by itself. Shimmy may result from significant
under-inflation of the tires, improper tires (load range, size, or type), or
vehicle modifications such as lift-kits. In the event that your vehicle
experiences shimmy, you should slowly reduce speed by either lifting off
the accelerator pedal or lightly applying the brakes. The shimmy will
cease as the vehicle speed decreases.
Maximum Permissible Inflation Pressure is 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 normallyTires, Wheels and Loading
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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 Tire Label.
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.
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 (see the Dissimilar spare
tire/wheel information section for description): Store and maintain at
60 psi (4.15 bar). For Full Size and Dissimilar spare tires (see the
Dissimilar spare tire/wheel information section for description): Store
and maintain at the higher of the front and rear inflation pressure as
shown on 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. Tires, Wheels and Loading
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U.S. DOT Tire Identification Number (TIN)
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.
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.
Tire Replacement Requirements
Your vehicle is equipped with tires designed to provide a safe ride and
handling capability.
WARNING: Only use replacement tires and wheels that are the
same size, load index, speed rating and type (such as P-metric
versus LT-metric or all-season versus all-terrain) as those originally
provided by Ford. The recommended tire and wheel size may be found
on either the Safety Compliance Certification Label or the Tire Label
which is located on the B-Pillar or edge of the driver’s door. If this
information is not found on these labels then you should contact your
authorized dealer as soon as possible. Use of any tire or wheel not
recommended by Ford 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, contact your authorized
dealer as soon as possible. Tires, Wheels and Loading
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WARNING: When mounting replacement tires and wheels, you
should not exceed the maximum pressure indicated on the
sidewall of the tire to set the beads without additional precautions
listed below. If the beads do not seat at the maximum pressure
indicated, re-lubricate and try again.
When inflating the tire for mounting pressures up to 20 psi (138 kPa)
greater than the maximum pressure on the tire sidewall, the following
precautions must be taken to protect the person mounting the tire:
1. Make sure that you have the correct tire and wheel size.
2. Lubricate the tire bead and wheel bead seat area again.
3. Stand at a minimum of 12 ft. (3.66 m) away from the tire wheel
assembly.
4. Use both eye and ear protection.
For a mounting pressure more than 20 psi (138 kPa) greater than the
maximum pressure, a Ford Dealer or other tire service professional
should do the mounting.
Always inflate steel carcass tires with a remote air fill with the person
inflating standing at a minimum of 12 ft. (3.66 m) away from the tire
wheel assembly.
Important: Remember to replace the wheel valve stems when the road
tires are replaced on your vehicle.
It is recommended that the two front tires or two rear tires generally be
replaced as a pair.
The tire pressure sensors mounted in the wheels are not designed to be
used in aftermarket wheels.
The use of wheels or tires not recommended by Ford Motor Company
may affect the operation of your Tire Pressure Monitoring System (if
equipped).
If the TPMS indicator is flashing, your TPMS is malfunctioning. Your
replacement tire might be incompatible with your TPMS, or some
component of the TPMS may be damaged (if equipped).
Safety practices
Driving habits have a great deal to do with your tire mileage and safety.
• Observe posted speed limits
• Avoid fast starts, stops and turns
• Avoid potholes and objects on the roadTires, Wheels and Loading
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• Rear Wheel Drive (RWD)
vehicles/Four Wheel Drive
(4WD)/All Wheel Drive (AWD)
vehicles (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 an 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.
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.Tires, Wheels and Loading
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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
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. Tires, Wheels and Loading
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