2006 FORD GT Owners Manual

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.
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 mph (130 km/h)N 87 mph (140 km/h)
Q 99 mph (159 km/h)R 106 mph (171 km/h) S 112 mph (180 km/h)
T 118 mph (190 km/h)
U 124 mph (200 km/h)
H 130 mph (210 km/h) V 149 mph (240 km/h)
W 168 mph (270 km/h) Y 186 mph (299 km/h)
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.
8. 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.
9. M+S or M/S: Mud and Snow, or
AT: All Terrain, or
AS: All Season.
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10.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.
11. Maximum Load: Indicates the maximum load in kilograms and
pounds that can be carried by the tire. Refer to the tire label or the
safety certification label, which is located on the B-Pillar or the edge of
the driver’s door, for the correct tire pressure for your vehicle.
12. 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
12) 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.
13. Maximum Permissible Inflation Pressure: Indicates the tire
manufacturers’ 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 either the tire label or certification 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, radial tubeless, etc.
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Additional information contained on the tire sidewall for “LT” type
tires
“LT” type tires have some additional
information beyond those of “P”
type tires; these differences are
described below:
1.LT: Indicates a tire, designated by
the Tire and Rim Association
(T&RA), that is intended for service
on light trucks.
2. Load Range/Load Inflation
Limits: Indicates the tire’s
load-carrying capabilities and its
inflation limits.
3. 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).
4. 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.
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Information on “T” type tires
“T” type tires have some additional
information beyond those of “P”
type tires; these differences are
described below:
T145/80D16 is an example of a tire
size.
Note:The temporary tire size for
your vehicle may be different from
this example.
1. T: Indicates a type of tire,
designated by the Tire and Rim
Association (T&RA), that is
intended for temporary service on
cars, SUVs, minivans and light
trucks.
2. 145: 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. 80: Indicates the aspect ratio which gives the tire’s ratio of height to
width. Numbers of 70 or lower indicate a short sidewall.
4. D: Indicates a “diagonal” type tire.
R: Indicates a “radial” type tire.
5. 16: 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.
Location of the tire label
You will find a tire label containing tire inflation pressure by tire size and
other important information located on the B-Pillar or the edge of the
driver’s door.
TIRE CARE
Improper or inadequate vehicle maintenance can also cause tires to wear
abnormally. Here are some of the important maintenance items:
Tire wear
Measure and inspect the tire tread on all your tires periodically.
Advanced and unusual tire wear can reduce the ability of tread to grip
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the road in adverse (wet, snowy, etc.) conditions. Visually check your
tires for uneven wear, looking for high and low areas or unusually
smooth areas. Also check for signs of tire damage.
When the tread is worn down to
1/16th of an inch (2 mm), tires must
be replaced to 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 should be replaced.
Inspect your tires frequently for any
of the following conditions and
replace them if one or more of the
following conditions exist:
•Fabric showing through the tire
rubber
• Bulges in the tread or sidewalls
• Cracks or cuts on the sidewalls
• Cracks in the tread groove
• Impact damage resulting from use
• Separation in the tread
• Separation in the sidewall
• Severe abrasion on the sidewall
If your vehicle has a leak in the exhaust system, a road tire or the spare
tire may be exposed to hot exhaust temperatures requiring the tire to be
replaced.
Tire tips
Your Ford GT is equipped with unique wheels and tires designed to
enhance performance and appearance. To continue providing this
performance, extra care must be taken when operating and maintaining
your vehicle.
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Tires
Your Ford GT is equipped with low profile, high performance tires that
are designed to optimize handling, steering and braking. These tires are
not designed for off-road or winter performance, and their ride, noise
and wear characteristics are different than other tires. Also, because of
their lower profile, the tires are more susceptible to damage due to
potholes and rough or unpaved roads. To ensure that your tires perform
as designed, it is important that you maintain your tires properly:
•Always maintain your tire pressures according to the tire information
label on the B-Pillar or the edge of the driver’s door using an accurate
gauge.
• Tire pressures are specified “cold” and should be checked after the
vehicle has been parked for at least 3 hours. Do not reduce pressure
of warm tires.
• Check your tire pressure often to maintain it properly. Tire pressure
can diminish over time and fluctuate with temperature.
• Do not overload your vehicle. Maximum vehicle and axle weights are
listed on the tire information placard.
• Extra caution should be taken when operating the vehicle near its
maximum load, including assuring proper tire pressure and reducing
speeds.
• Extra caution should be taken when operating on rough roads to avoid
impacts that could cause tire damage.
• In the event that you encounter an abnormally harsh impact, inspect
you tires for damage.
• Inspect your tires for damage on a regular basis. If a tire is damaged,
replace it immediately.
• Proper suspension alignment is critical for maximum performance and
optimal tire wear. If you notice uneven tire wear, have you alignment
checked.
• Rotate tires as recommended in this section of the Owner Guide.
• When replacing tires, the only way to assure original performance is to
use the original equipment tire.
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Wheels
Your Ford GT is equipped with unique wheels matched to the tires.
These wheels are more susceptible to damage due to their diameter,
width and low profile tires. To avoid damage to your wheels:
•Maintain proper tire pressure (see “Tires” previously listed).
• When installing wheels, always torque lug nuts to specification with a
torque wrench.
• Inspect your wheels for damage on a regular basis. If a wheel is
damaged, replace it immediately.
• In the event that you encounter an abnormally harsh impact, inspect
the outer diameter of your wheels, both inside and out, for damage
Operating a performance vehicle at higher than normal speeds
Your Ford GT is capable of operating at higher than normal speeds and is
equipped with tires rated for the vehicles’ maximum speed. However, it
is important to remember to always drive safely, obey all traffic laws and
only operate your Ford GT at higher than normal speeds at locations and
under conditions where such can be done safely. Also, before operating
your vehicle at higher than normal speeds:
• Maintain your tire pressures according to the tire information and high
speed warning labels located on the B-pillar or the edge of the driver’s
door.
• Inspect wheels and tires for wear and damage. Replace any damaged
wheels or tires.
Winter driving
The original equipment tires on your Ford GT are designed for maximum
performance in dry and wet conditions. They are not designed for winter
use on ice or snow and cannot be used with snow chains or other tire
mounted traction aids.
Tire and wheel alignment
A bad jolt from hitting a curb or pothole can cause the front end of your
vehicle to become misaligned or cause damage to your tires. If your
vehicle seems to pull to one side when you’re driving, the wheels may be
out of alignment. Have a qualified technician at a Ford or
Lincoln/Mercury dealer check the wheel alignment periodically.
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Wheel misalignment in the front or the rear can cause uneven and rapid
treadwear of your tires and should be corrected by a qualified technician
at a Ford or Lincoln/Mercury dealer. Front wheel drive (FWD) vehicles
and those with an independent rear suspension (if equipped) may
require alignment of all four wheels.
The tires should also be balanced periodically. An unbalanced tire and
wheel assembly may result in irregular tire wear.
Tire rotation
Because your vehicle is equipped with unique larger tires on the rear
wheels, you can only rotate tires side to side. You must not rotate tire in
a crisscross pattern or front to rear. If you notice that the tires wear
unevenly, have them checked.
Rotating your tires at the recommended interval (as indicated in the
Scheduled Maintenancechapter) will help your tires wear more evenly,
providing better tire performance and longer tire life. Unless otherwise
specified, rotate the tires approximately every 5,000 miles (8,000 km).
• Tire rotation
Sometimes irregular tire wear can be corrected by rotating the tires.
Note: If your tires show uneven wear ask a qualified technician at a
Ford or Lincoln/Mercury dealership to check for and correct any wheel
misalignment, tire imbalance or mechanical problem involved before tire
rotation.
Note: After having your tires rotated, inflation pressure must be checked
and adjusted to the vehicle requirements.
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