2005 Mercury Grand Marquis Owner's Manuals

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.
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Owners Guide (post-2002-fmt)
USA(fus)
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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 either the Safety Compliance
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.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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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.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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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 Safety Compliance Certification Label
You will find a Safety Compliance Certification 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. Refer to the payload
description and graphic in theVehicle loading — with and without a
trailersection.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
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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
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.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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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
If your vehicle is stuck in snow, mud, sand, etc.,do notrapidly
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.
Never spin the tires in excess of the 35 mph (55 km/h) point
indicated on the speedometer.
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,
deflate it, remove wheel and replace it with your spare tire and wheel. If
you cannot detect a cause, have the vehicle towed to the nearest repair
facility or tire dealer to have the vehicle inspected.
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.
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.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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The tires should also be balanced periodically. An unbalanced tire and
wheel assembly may result in irregular tire wear.
Tire rotation
Rotating your tires at the recommended interval (as indicated in the
scheduled maintenance informationthat comes with your vehicle) 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).
•Front Wheel Drive (FWD)
vehicles (front tires at top of
diagram)
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
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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 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: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.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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