2004 LINCOLN NAVIGATOR tires

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 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.
13. Maximum Permissible Inflation Pressure: Tire manufactures
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 structure by the trailing edge of the driver ’ s door or the
edge of the driver ’ s door. The cold inflation pressure should never be set
lower than the recommended pressure on the label.
Note: You may not find this information on all tires because it is not
required by federal law.
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 than 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 tires
load-carrying capabilities and its
inflation limits.
3. Maximum Load Dual kg (lbs.)
at kPa (psi) cold: Indicates the
maximum load and tire pressure
when the tire is used as a dual; a
dual is defined as when four tires are put on the rear axle (a total of six
or more tires on the vehicle).
4. Maximum Load Single kg (lbs.) at kPa (psi) cold: Indicates the
maximum load and tire pressure when the tire is used as a single; a
single is defined as when two tires (total) are put on the rear axle.
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Information on “ T ” type tires
T145/80D16 is an example of a tire
size.
Note: The temporary tire size for
your vehicle may be different than
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 tires 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 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 inflation pressure
Use a tire gauge to check the tire inflation pressure, including the spare,
at least monthly and before long trips. You are strongly urged to buy a
reliable tire pressure gauge, as automatic service station gauges may be
inaccurate. SPARETIRE
T
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M
P
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R
A
R
Y
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T
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T T145/80D16105M
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Use the recommended cold inflation pressure for optimum tire
performance and wear. Under-inflation or over-inflation may cause
uneven treadwear patterns.
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!
When weather temperature changes occur, tire inflation pressures also
change. A 10 degree temperature change causes a corresponding drop of
7 kPa (1 psi) in inflation pressure. Check your tire pressures frequently
and adjust them to the proper pressure which can be found on the tire
label or certification label.
If checking tire pressure when the tire is hot, (i.e. driven more than 1.6
km [1mile]), 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.
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 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. Never “ bleed ” or reduce air
pressure when tires are hot.
2. Remove the cap from the valve on one tire, then firmly press the tire
gauge onto the valve.
3. Add 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 require higher inflation pressure than the other
tires.
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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, bulges or
other irregularities.
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 damage to your tires. If your vehicle
seems to pull to one side, vibrate or shake when you ’ re driving, the
wheels may be out of alignment. Have a qualified technician at a
reputable repair facility 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 reputable repair facility. Front wheel drive (FWD) vehicles, and
those with independent front suspension 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
Rotating your tires at the recommended interval (as indicated in the
Service Maintenance Guide that 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
8,000 km (5,000 miles).
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• Front Wheel Drive (FWD)
vehicles (front tires at top of
diagram)
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• Rear Wheel Drive (RWD)
vehicles/Four Wheel Drive (4WD)
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
reputable repair facility to check for and correct any wheel misalignment,
tire imbalance or mechanical problem involved before tire rotation.
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 4
mm (1/16th of an inch), 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
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the tread is worn down to 4mm (1/16th of an inch). When you see 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.
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 you vehicle is stuck in snow, mud, sand, etc., 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.
Tire explosions can cause death, personal injury or property
damage. Do not allow anyone to stand near, or directly ahead or
behind the spinning tire.
Never spin the tires in excess of the 55 km/h (35 mph) 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
2004 Navigator (nav)
Owners Guide (post-2002-fmt)
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