2018 FORD GT Owners Manual

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. Speed rating
Letter
rating
81 mph (130 km/h)
M
87 mph (140 km/h)
N
93 mph (150 km/h)
P
99 mph (160 km/h)
Q
106 mph (170 km/h)
R
112 mph (180 km/h)
S
118 mph (190 km/h)
T
124 mph (200 km/h)
U
130 mph (210 km/h)
H
149 mph (240 km/h)
V
168 mph (270 km/h)
W Speed rating
Letter
rating
186 mph (300 km/h)
Y
>
186 mph
(300 km/h)
ZR
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
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
manufacturers' 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.
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The tire suppliers may have
additional markings, notes or
warnings such as standard load
or radial tubeless.
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 driver
’s
side door opening.
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
(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
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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.
Maximum Inflation Pressure is
the tire manufacturer's maximum
permissible pressure and 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
(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 Safety
Compliance Certification Label or
Tire Label.
When weather temperature
changes occur, tire inflation
pressures also change. A
43°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.
Note: If you are checking tire
pressure when the tire is hot, (for
example, driven more than
1 mi
(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 pressing 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.
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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.
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.
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
one sixteenth 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 one
sixteenth 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.
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Age
WARNINGS
Tires degrade over time
depending on many factors
such as weather, storage
conditions, and conditions of use
(load, speed, inflation pressure)
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. U.S. DOT Tire Identification
Number
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. 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, 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.
WARNINGS
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
(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 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
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WARNINGS
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. The use of
non-recommended tires and
wheels could cause steering,
suspension, axle, transfer case or
power transfer unit failure. If you
have questions regarding tire
replacement, contact your
authorized dealer as soon as
possible. To reduce the risk of serious
injury, 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 (1.38 bar) greater than the
maximum pressure on the tire
sidewall, the following
precautions must be taken to
protect the person mounting the
tire: •
Make sure that you have the
correct tire and wheel size.
• Lubricate the tire bead and
wheel bead seat area again.
• Stand at a minimum of
12 ft
(3.66 m) away from the wheel
and tire assembly.
• Use both eye and ear
protection. WARNINGS
For a mounting pressure
more than
20 psi (1.38 bar)
greater than the maximum
pressure, a Ford 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 wheel and tire 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 (originally installed
on your vehicle) are not designed
to be used in aftermarket wheels.
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The use of wheels or tires not
recommended by Ford Motor
Company may affect the
operation of your tire pressure
monitoring system.
If the tire pressure monitoring
system indicator is flashing, your
system is malfunctioning. Your
replacement tire might be
incompatible with your tire
pressure monitoring system, or
some component of the system
may be damaged.
Safety Practices
WARNINGS
If your vehicle is stuck in
snow, mud or sand, do not
rapidly spin the tires; spinning the
tires can tear the tire and cause
an explosion. A tire can explode in
as little as three to five seconds. Do not spin the wheels at
over 34 mph (55 km/h). The
tires may fail and injure a
passenger or bystander. 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.
*Do not run over curbs or hit the
tire against a curb when parking. Highway Hazards
No matter how carefully you drive
there
’s always the possibility that
you may eventually have a flat tire
on the highway. Drive slowly to the
closest safe area out of traffic.
This may further damage the flat
tire, but your safety is more
important.
If you feel a sudden vibration or
ride disturbance while driving, or
you suspect your tire or vehicle
has been damaged, immediately
reduce your speed. Drive with
caution until you can safely pull
off the road. Stop and inspect the
tires for damage. If a tire is
under-inflated or damaged, see
the instructions on use of the tire
sealant and inflater kit at the
beginning of this section. If the kit
cannot provide a temporary tire
inflation, contact an authorized
dealer.
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 an authorized
dealer check the wheel alignment
periodically.
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