2008 Mercury Grand Marquis tire pressure

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.
Maximum Permissible Inflation Pressureis the tire manufacturer’s
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 the Safety Compliance Certification Label 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 10°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.
If you are checking tire pressure when the tire is hot, (i.e. driven more
than 1 mile [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
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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 pushing 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.
Note:Some spare tires operate at a higher inflation pressure than the
other tires. For T-type/mini-spare tires (seeDissimilar Spare
Tire/Wheel Informationsection for description): Store and maintain at
60psi (4.15 bar). For Full Size and Dissimilar spare tires (seeDissimilar
Spare Tire/Wheel Informationsection 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 CARE
Inspecting your tires
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 for holes or cuts that may permit air leakage from
the tire and make necessary repairs. Also 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:
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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.
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.
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
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
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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 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 feet away from the tire wheel assembly.
4. Use both eye and ear protection.
For a mounting pressure more than 20 psi 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. 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 (originally installed on
your vehicle) 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
•Do not run over curbs or hit the tire against a curb when parking
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•Rear Wheel Drive (RWD)
vehicles/Four Wheel Drive
(4WD)/ All Wheel Drive (AWD)
vehicles (front tires at top of
diagram)
Sometimes irregular tire wear can be corrected by rotating the tires.
Note:If your tires show uneven wear ask an authorized dealer to check
for and correct any wheel misalignment, tire imbalance or mechanical
problem involved before tire rotation.
Note:Your vehicle may be equipped with a dissimilar spare tire/wheel. A
dissimilar spare tire/wheel is defined as a spare tire and/or wheel that is
different in brand, size or appearance from the road tires and wheels. If
you have a dissimilar spare tire/wheel it is intended for temporary use
only and should not be used in a tire rotation.
Note:After having your tires rotated, inflation pressure must be checked
and adjusted to the vehicle requirements.
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 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.)
1.P:Indicates a tire, designated by
the Tire and Rim Association
(T&RA), that may be used for
service on cars, SUVs, minivans and
light trucks.
Note:If your tire size does not
begin with a letter this may mean it
is designated by either ETRTO
(European Tire and Rim Technical Organization) or JATMA (Japan Tire
Manufacturing Association).
2.215: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.
3.65:Indicates the aspect ratio which gives the tire’s ratio of height to
width.
4.R:Indicates a “radial” type tire.
5.15: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.
6.95: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 Guide.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.
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.
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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.
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 Safety Compliance
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.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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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 the Safety Compliance Certification
Label 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, radial tubeless, etc.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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