2011 FORD F550 warning

Power is supplied to all four wheels through a transfer case or power
transfer unit. 4WD vehicles allow you to select different drive modes as
necessary. Information on transfer case operation and shifting procedures
can be found in the Driving chapter. Information on transfer case
maintenance can be found in the Maintenance and Specifications
chapter. You should become thoroughly familiar with this information
before you operate your vehicle.
On some 4WD models, the initial shift from two-wheel drive to 4WD
while the vehicle is moving can cause a momentary clunk and ratcheting
sound. These sounds are normal as the front drivetrain comes up to
speed and is not cause for concern.
WARNING: Do not become overconfident in the ability of 4WD
vehicles. Although a 4WD vehicle may accelerate better than
two-wheel drive vehicle in low traction situations, it won’t stop any
faster than two-wheel drive vehicles. Always drive at a safe speed.
How your vehicle differs from other vehicles
SUVs and trucks can differ from
some other vehicles in a few
noticeable ways. Your vehicle may
be:
• Higher – to allow higher load
carrying capacity and to allow it
to travel over rough terrain
without getting hung up or
damaging underbody components.
• Shorter – to give it the capability
to approach inclines and drive
over the crest of a hill without
getting hung up or damaging
underbody components. All other
things held equal, a shorter
wheelbase may make your vehicle
quicker to respond to steering inputs than a vehicle with a longer
wheelbase. Tires, Wheels and Loading
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USA (fus)

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.
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, Wheels and Loading
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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.
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 Tires, Wheels and Loading
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Owners Guide, 4th Printing
USA (fus)

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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2011 F-250/350/450/550 (f23)
Owners Guide, 4th Printing
USA (fus)

WARNING: Stay out of the trajectory (1) as indicated in the
illustration.
TIRE CARE
Inspecting your tires and wheel valve stems
Periodically inspect the tire treads for uneven or excessive wear and
remove objects such as stones, nails or glass that may be wedged in the
tread grooves. Check the tire and valve stems for holes, cracks, or cuts
that may permit air leakage and repair or replace the tire and replace
the valve stem. Inspect the tire sidewalls for cracking, cuts, bruises and
other signs of damage or excessive wear. 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 or show
signs of excessive wear should not be used because they are more likely
to blow out or fail.Tires, Wheels and Loading
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USA (fus)

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.
WARNING: 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 six 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 six years due to aging even if it has not been used. Tires, Wheels and Loading
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USA (fus)

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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Owners Guide, 4th Printing
USA (fus)

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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2011 F-250/350/450/550 (f23)
Owners Guide, 4th Printing
USA (fus)