2011 FORD F550 wheel size

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. 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.Tires, Wheels and Loading
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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 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 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.Tires, Wheels and Loading
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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.
7. Check the sidewalls to make sure there are no gouges, cuts or bulges.
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 tire 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.
WARNING: An inflated tire and rim can be very dangerous if
improperly used, serviced or maintained. To reduce the risk of
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. 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, an authorized 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 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.
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 road Tires, Wheels and Loading
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Tire rotation
Rotating your tires at the recommended interval (as indicated in the
Scheduled Maintenance chapter) will help your tires wear more evenly,
providing better tire performance and longer tire life.
• Rear-wheel drive (RWD)
vehicles/Four-wheel drive (4WD)
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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• Dual rear wheel (DRW) vehicles –
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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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.
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. Tires, Wheels and Loading
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