wheel size FORD F-550 2021 Owners Manual

Note:
4x4 low mode is not intended for use
on dry pavement.
1. Bring the vehicle to a speed of 3 mph
(5 km/h) or less.
2. Place the transmission in neutral (N).
3. Move the 4WD control to the preferred
position.
The information display will display a
message indicating a 4X4 shift is in
progress. The information display will then
display the system mode selected. If any
of the above shift conditions are not met,
the shift will not occur and the information
display will display information guiding the
driver through the proper shifting
procedures.
If a message in the information display
shows a Shift Delayed Pull Forward
message, a transfer case gear tooth
blockage is present. To alleviate this
condition, place the transmission in a
forward gear, move the vehicle forward
approximately
5 ft (1.5 m), and shift the
transmission back to neutral to allow the
transfer case to complete the range shift.
Entering and Exiting Rock Crawl
Mode with Tremor Package
(If
Equipped) •
To enter rock crawl, your vehicle must
be in 4x4 low.
• Press the drive mode button on the
shifter column to bring up the
information display and select rock
crawl mode.
• With the switch in 4x4 low position,
press rock crawl mode again to
deactivate it. •
You can now perform a shift out of 4x4
low.
• Refer to Shifting to or from 4L (4x4
low) as described previously for proper
operation of 4x4 low in this procedure.
Operating 4WD Vehicles with
Spare or Mismatched Tires
On four-wheel drive vehicles, the size of
the spare tire can affect the 4X4 system.
If there is a significant difference between
the size of the spare tire and the remaining
tires, you may have limited four-wheel
drive functionality.
When driving with the full-size, dissimilar
spare wheel and tire assembly, we
recommend that you do not:
• Exceed
50 mph (80 km/h) with a 4WD
mode turned on.
• Turn on a 4WD mode unless the
vehicle is stationary.
• Use a 4WD mode on dry pavement.
When driving with the full-size, dissimilar
spare wheel and tire assembly, you may
have limited 4WD functionality, especially
when driving in a mechanically locked 4WD
mode. You may experience the following:
• Additional noise from the transfer case
or other drive components.
• Difficulty shifting out of a mechanically
locked 4WD mode.
Use of a dissimilar spare wheel and tire
assembly may lead to impairment of the
following:
• Comfort and noise.
• Winter weather driving capability.
• Wet driving capability.
• Four-wheel drive capability.
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(If Equipped)E225315

For 4WD vehicles
Pull the 4WD control knob toward you.
For 2WD vehicles
Turn the control to ON.
Once the indicator light
illuminates in the information
display, both rear wheel axle
shafts will be locked together providing
added traction.
If the indicator does not come on, or the
indicator turns off while driving, one of the
following has occurred:
• The vehicle speed is too high.
• The left and right rear wheel speed
difference is too high during an
engagement attempt. •
The system has malfunctioned and is
accompanied by a message in the
information display. See your
authorized Ford dealer for assistance.
• The vehicle is experiencing an anti-lock
brake activation.
Operating ELD With a Spare or
Mismatched Tires
On vehicles with an ELD, the size of the
spare tire can affect performance of the
system. If there is a significant difference
between the two rear tires, you may have
limited ELD functionality. If the electronic
locking differential has difficulty
disengaging, release the accelerator pedal
and turn the steering wheel in the opposite
direction when rolling. We recommend
engaging and disengaging the ELD at a
stop when you mount a spare on the rear
axle.
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PRINCIPLE OF OPERATION
WARNING: Vehicle modifications
involving braking system, aftermarket
roof racks, suspension, steering system,
tire construction and wheel and tire size
may change the handling characteristics
of your vehicle and may adversely affect
the performance of the electronic
stability control system. In addition,
installing any stereo loudspeakers may
interfere with and adversely affect the
electronic stability control system. Install
any aftermarket stereo loudspeaker as
far as possible from the front center
console, the tunnel, and the front seats
in order to minimize the risk of interfering
with the electronic stability control
sensors. Reducing the effectiveness of
the electronic stability control system
could lead to an increased risk of loss of
vehicle control, vehicle rollover, personal
injury and death. WARNING:
Remember that even
advanced technology cannot defy the
laws of physics. It’ s always possible to
lose control of a vehicle due to
inappropriate driver input for the
conditions. Aggressive driving on any
road condition can cause you to lose
control of your vehicle increasing the risk
of personal injury or property damage.
Activation of the electronic stability
control system is an indication that at
least some of the tires have exceeded
their ability to grip the road; this could
reduce the operator ’s ability to control
the vehicle potentially resulting in a loss
of vehicle control, vehicle rollover,
personal injury and death. If your
electronic stability control system
activates, SLOW DOWN.
The system automatically turns on each
time you switch the ignition on. If a fault occurs in either the stability
control or the traction control system, you
may experience the following conditions:
•
The stability and traction control light
illuminates steadily.
• The stability control and traction
control systems do not enhance your
vehicle's ability to maintain traction of
the wheels.
• The Adaptive Steering system (if
equipped) automatically changes the
steering function to a fixed steering
ratio. See
Adjusting the Steering
Wheel (page 81).
If a driving condition activates either the
stability control or the traction control
system you may experience the following
conditions:
• The stability and traction control light
flashes.
• Your vehicle slows down.
• Reduced engine power.
• A vibration in the brake pedal.
• The brake pedal is stiffer than usual.
• If the driving condition is severe and
your foot is not on the brake, the brake
pedal may move as the system applies
higher brake force.
The stability control system has several
features built into it to help you maintain
control of your vehicle:
Electronic Stability Control
The system enhances your vehicle ’s ability
to prevent skids or lateral slides by
applying brakes to one or more of the
wheels individually and, if necessary,
reducing engine power.
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•
Allow more distance for stopping with
a trailer attached. Anticipate stops and
brake gradually.
• Avoid parking on a grade. However, if
you must park on a grade:
1. Turn the steering wheel to point your vehicle tires away from traffic flow.
2. Set your vehicle parking brake.
3. Place the transmission in park (P).
4. Place wheel chocks in front and back of the trailer wheels. (Chocks not
included with vehicle.)
Your vehicle may be equipped with a
temporary or conventional spare tire. A
"temporary" spare tire is different in size
(diameter or width), tread-type
(All-Season or All Terrain) or is from a
different manufacturer than the road tires
on your vehicle. Consult information on the
tire label or Safety Compliance label for
limitations when using.
Launching or Retrieving a Boat or
Personal Watercraft (PWC)
Note: Disconnect the wiring to the trailer
before backing the trailer into the water.
Note: Reconnect the wiring to the trailer
after
you remove the trailer from the water.
When backing down a ramp during boat
launching or retrieval:
• Do not allow the static water level to
rise above the bottom edge of the rear
bumper.
• Do not allow waves to break higher
than
6 in (15 cm) above the bottom
edge of the rear bumper.
Exceeding these limits may allow water to
enter vehicle components:
• Causing internal damage to the
components.
• Affecting driveability, emissions, and
reliability. Replace the rear axle lubricant anytime
the rear axle has been submerged in water.
Water may have contaminated the rear
axle lubricant, which is not normally
checked or changed unless a leak is
suspected or other axle repair is required.
TOWING THE VEHICLE ON
FOUR WHEELS
WARNING:
If your vehicle has a
steering wheel lock make sure the
ignition is in the accessory or on position
when being towed.
Emergency Towing
If your vehicle becomes inoperable
(without access to wheel dollies,
car-hauling trailer, or flatbed transport
vehicle), it can be flat-towed (all wheels
on the ground, regardless of the powertrain
and transmission configuration) under the
following conditions:
• Your vehicle is facing forward for
towing in a forward direction.
• Place the transmission in neutral (N).
If you cannot move the transmission
into neutral (N), you may need to
override it. See
Transmission (page
207).
• Maximum speed is 35 mph (56 km/h).
• Maximum distance is
50 mi (80 km).
Recreational Towing
Note: Put your climate control system in
recirculated air mode to prevent exhaust
fumes from entering your vehicle.
See
Climate Control (page 143).
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ECONOMICAL DRIVING
Your fuel economy is affected by several
things, such as how you drive, the
conditions you drive under, and how you
maintain your vehicle.
You may improve your fuel economy by
keeping these things in mind:
•
Accelerate and slow down in a smooth,
moderate fashion.
• Drive at steady speeds without
stopping.
• Anticipate stops; slowing down may
eliminate the need to stop.
• Combine errands and minimize
stop-and-go driving.
• Close the windows for high-speed
driving.
• Drive at reasonable speeds (traveling
at 55 mph [88 km/h] uses 15% less
fuel than traveling at 65 mph [105
km/h]).
• Keep the tires properly inflated and use
only the recommended size.
• Use the recommended engine oil.
• Perform all regularly scheduled
maintenance.
Avoid these actions; they reduce your fuel
economy:
• Sudden accelerations or hard
accelerations.
• Revving the engine before turning it off.
• Idle for periods longer than one minute.
• Warm up your vehicle on cold
mornings.
• Use the air conditioner or front
defroster.
• Use the speed control in hilly terrain.
• Rest your foot on the brake pedal while
driving. •
Drive a heavily loaded vehicle or tow a
trailer.
• Carry unnecessary weight
(approximately 1 mpg [0.4 km/L] is
lost for every 400 lb [180 kilogram] of
weight carried).
• Driving with the wheels out of
alignment.
Conditions
• Heavily loading a vehicle or towing a
trailer may reduce fuel economy at any
speed.
• Adding certain accessories to your
vehicle (for example bug deflectors,
rollbars, light bars, running boards, ski
racks or luggage racks) may reduce
fuel economy.
• To maximize the fuel economy, drive
with the tonneau cover installed (if
equipped).
• Using fuel blended with alcohol may
lower fuel economy.
• Fuel economy may decrease with lower
temperatures during the first 5–10 mi
(12 –16 km) of driving.
• Driving on flat terrain offers improved
fuel economy as compared to driving
on hilly terrain.
• Transmissions give their best fuel
economy when operated in the top
cruise gear and with steady pressure
on the gas pedal.
• Four-wheel-drive operation (if
equipped) is less fuel efficient than
two-wheel-drive operation.
OFF-ROAD DRIVING
Note: The following off-road driving
information applies to Tremor package
equipped vehicles only.
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GENERAL INFORMATION
Use only approved wheel and tire sizes,
using other sizes could damage your
vehicle. If you change the diameter of the
tires from that fitted at the factory, the
speedometer may not display the correct
speed. If you intend to change the size of
the wheels from that fitted by the
manufacturer, you can check the suitability
with an authorized dealer.
Additional information related to the
functionality and maintenance of your tires
can be found later in this chapter. See Tire
Care (page 404).
You can find the recommended tire
inflation pressures can on the Tire Label,
which is on the B-pillar or the edge of the
driver door. You can also find this
information on the Safety Compliance
Certification Label, affixed to either the
door hinge pillar, door-latch post, or the
door edge that meets the door latch post;
next to the driver seating position.
We strongly recommend maintaining these
tire pressures at all times. Failure to follow
the tire pressure recommendations can
cause uneven treadwear patterns, reduced
fuel economy, and adversely affect the
way your vehicle handles.
Note: Check and set the tire pressure at the
ambient temperature in which you are
intending to drive your vehicle and when the
tires are cold.
Note: Check your tire pressures at least
once per month.
If your vehicle has a spare tire, set the
pressure to the highest value given for your
vehicle and tire size combination. Notice to utility vehicle and truck
owners WARNING:
Utility vehicles have a
significantly higher rollover rate than
other types of vehicles. WARNING:
Vehicles with a higher
center of gravity (utility and four-wheel
drive vehicles) handle differently than
vehicles with a lower center of gravity
(passenger cars). Avoid sharp turns,
excessive speed and abrupt steering in
these vehicles. Failure to drive cautiously
increases the risk of losing control of your
vehicle, vehicle rollover, personal injury
and death. WARNING:
In a rollover crash, an
unbelted person is significantly more
likely to die than a person wearing a
seatbelt. WARNING:
Do not become
overconfident in the ability of four-wheel
drive vehicles. Although a four-wheel
drive vehicle may accelerate better than
a 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.
Utility vehicles and trucks handle
differently than passenger cars in the
various driving conditions that are
encountered on streets, highways and
off-road. Utility vehicles and trucks are not
designed for cornering at speeds as high
as passenger cars any more than low-slung
sports cars are designed to perform
satisfactorily under off-road conditions.
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Study your owner's manual and any
supplements for specific information about
equipment features, instructions for safe
driving and additional precautions to
reduce the risk of an accident or serious
injury.
Four-wheel drive system (If Equipped)
WARNING:
Do not become
overconfident in the ability of four-wheel
drive vehicles. Although a four-wheel
drive vehicle may accelerate better than
a 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.
A vehicle equipped with four-wheel drive,
when selected, has the ability to use all
four wheels to power itself. This increases
traction which may enable you to safely
drive over terrain and road conditions that
a conventional two-wheel drive vehicle
cannot.
Power is supplied to all four wheels
through a transfer case or power transfer
unit. Four-wheel drive vehicles allow you
to select different modes as necessary. For
information on transfer case operation and
shifting procedures, See
Four-Wheel
Drive (page 213). For information on
transfer case maintenance, See
Maintenance (page 348). You should
become thoroughly familiar with this
information before you operate your
vehicle.
On some four-wheel drive vehicles, the
initial shift from two-wheel to four-wheel
drive when the vehicle is moving can cause
a momentary clunk and ratcheting sound.
These sounds are normal and are not
cause for concern. In four-wheel drive vehicles, the size of the
spare tire relative to the remaining tires can
have an effect on the 4x4 system. If there
is a significant difference between the size
of a spare and the remaining tires,
four-wheel drive functionality may be
limited.
See Using Four-Wheel Drive
(page 213).
How your vehicle differs from
other vehicles
Sport utility vehicles 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.
• Narrower - to provide greater
maneuverability in tight spaces,
particularly in off-road use.
As a result of the above dimensional
differences, Sport utility vehicles and
trucks often have a higher center of gravity
and a greater difference in center of gravity
between the loaded and unloaded
condition. These differences that make
your vehicle so versatile also make it
handle differently than an ordinary
passenger car.
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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.
Temperature A B C 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.
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.
Glossary of Tire Terminology
*
Tire label: A label showing the
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 set
pressure. For example: For
P-metric tires
35 psi (2.4 bar) and
for Metric tires 36 psi (2.5 bar).
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
42 psi
(2.9 bar). Increasing the inflation
pressure beyond this pressure will
not increase the tire ’s load
carrying capability.
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*kPa: Kilopascal, a metric unit of
air pressure.
*
PSI: Pounds per square inch, a
standard unit of air pressure.
*
Cold tire 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 kilometers).
*
Recommended inflation
pressure: The cold inflation
pressure found on the Safety
Compliance Certification Label
(affixed to either the door hinge
pillar, door-latch post, or the door
edge that meets the door-latch
post, next to the driver's seating
position), 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. Information Contained on the
Tire Sidewall
Both United States 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.
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).
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I
J
KL
M
A
B
CDEFGE142543

A.
P: Indicates a tire, designated
by the Tire and Rim Association,
that may be used for service on
cars, sport utility vehicles,
minivans and light trucks. Note:
If
your tire size does not begin with
a letter this may mean it is
designated by either the European
Tire and Rim Technical
Organization or the Japan Tire
Manufacturing Association.
B. 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.
C. 65:
Indicates the aspect ratio
which gives the tire's ratio of
height to width.
D. R:
Indicates a radial type tire.
E. 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.
F. 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 manual. 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. G.
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. mph ( km/h)
Letter
rating
81 (130)
M
87 (140)
N
99 (159)
Q
106 (171)
R
112 (180)
S
118 (190)
T
124 (200)
U
130 (210)
H
149 (240)
V
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