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Power is supplied to all four wheels through a transfer case or power
transfer unit. Four-wheel drive vehicles allow you to select different drive
modes as necessary. You can find information on transfer case operation
and shifting procedures in theTransmissionchapter. You can find
information on transfer case maintenance in the Maintenancechapter.
You should become thoroughly familiar with this information before you
operate your vehicle.
On some four-wheel drive models, the initial shift from two-wheel drive
to four-wheel drive 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 are not cause for concern.
How Your Vehicle Differs from Other Vehicles
Sport-utility vehicles, vans 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.
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•Narrower – to provide greater
maneuverability in tight spaces,
particularly in off-road use.
As a result of the above dimensional
differences, sport-utility vehicles,
vans and trucks often will 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.
TIRE CARE
Information About Uniform Tire Quality Grading Tire Quality Grades apply to new
pneumatic passenger car tires. The Tire
Quality Grades can be found where
applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
• Treadwear 200 Traction AA Temperature A
These Tire Quality Grades are determined by standards that the United
States Department of Transportation has set.
Tire Quality Grades apply to new pneumatic passenger car tires. They do
not apply to deep tread, winter-type snow tires, space-saver or
temporary use spare tires, light truck or LT type tires, tires with nominal
rim diameters of 10 to 12 inches or limited production tires as defined in
Title 49 Code of Federal Regulations Part 575.104(c)(2).
U.S. Department of Transportation-Tire quality grades: The U.S.
Department of Transportation requires Ford Motor Company to give you
the following information about tire grades exactly as the government
has written it.
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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 1
1 2times 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
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.
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 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 set pressure. For example: For P-metric tires 35 psi
(2.4 bar) or 36 (2.5 bar) depending on tire size and for Metric tires
36 psi (2.5 bar). Increasing the inflation pressure beyond this pressure
will not increase the tire 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.
• 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 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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Information on P Type TiresP215/65R15 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.)
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.
H
I
J
KL
M
A
B
CDEFG
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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.
Letter rating Speed rating - mph (km/h)
M 81 (130)
N 87 (140)
Q 99 (159)
R 106 (171)
S 112 (180)
T 118 (190)
U 124 (200)
H 130 (210)
V 149 (240)
W 168 (270)
Y 186 (299 )
Note: For tires with a maximum speed capability over 149 mph
(240 km/h), tire manufacturers sometimes use the letters ZR. For
those with a maximum speed capability over 186 mph (299 km/h), tire
manufacturers always use the letters ZR.
H. U.S. DOT Tire Identification Number (TIN): 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.
I. M+S or M/S: Mud and Snow, or
AT: All Terrain, or
AS: All Season.
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J.Tire Ply Composition and Material Used: Indicates the number of
plies or the number of layers of rubber-coated fabric in the tire tread and
sidewall. Tire manufacturers also must indicate the ply materials in the
tire and the sidewall, which include steel, nylon, polyester, and others.
K. Maximum Load: Indicates the maximum load in kilograms and
pounds that can be carried by the tire. See 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), for the correct tire pressure for your vehicle.
L. Treadwear, Traction and Temperature Grades
• 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.
• Traction: 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: 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.
M. Maximum Inflation Pressure: Indicates the tire manufacturer’s
maximum permissible pressure or the pressure at which the maximum
load can be carried by the tire. This pressure is normally higher than the
vehicle manufacturer’s recommended cold inflation pressure, which can
be 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 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 vehicle label.
The tire suppliers may have additional markings, notes or warnings, such
as standard load or radial tubeless.
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Additional Information Contained on the Tire Sidewall for LT Type
TiresLT type tires have some additional
information beyond those of P type
tires. These differences are
described below.
Note:Tire Quality Grades do not
apply to this type of tire.
A. LT: Indicates a tire, designated
by the Tire and Rim Association,
that is intended for service on light
trucks.
B. Load Range/Load Inflation
Limits: Indicates the tire’s
load-carrying capabilities and its
inflation limits.
C. Maximum Load Dual lb (kg) at psi (kPa) cold: Indicates the
maximum load and tire pressure when the tire is used as a dual, defined
as four tires on the rear axle (a total of six or more tires on the vehicle).
D. Maximum Load Single lb (kg) at psi (kPa) cold: Indicates the
maximum load and tire pressure when the tire is used as a single,
defined as two tires (total) on the rear axle.
A
BC
BD
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