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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.
WARNING: Age
Tires degrade over time depending on many factors such as
weather, storage conditions, and conditions of use (such as 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.
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
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
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.
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Highway Hazards
No matter how carefully you drive, there is 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 the 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 are driving, the wheels
may be out of alignment. Have an authorized 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 an authorized
dealer. Front-wheel drive vehicles and those with an independent rear
suspension 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
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 and
wheel assembly. A dissimilar spare tire and wheel assembly is defined as
a spare tire or wheel that is different in brand, size or appearance from
the road tires and wheels. If you have a dissimilar spare tire and wheel
assembly, 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.
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•Chains are not recommended for use on the P275/55R20 tire.
•Install chains securely, verifying that the chains do not touch any
wiring, brake lines or fuel lines.
•Do not exceed 30 mph (48 km/h) with tire chains on your vehicle.
•Drive cautiously. If you hear the chains rub or bang against your
vehicle, stop and retighten the chains. If this does not work, remove
the chains to prevent damage to your vehicle.
•Remove the tire chains when they are no longer needed. Do not use
tire chains on dry roads.
TIRE PRESSURE MONITORING SYSTEM
WARNING:The tire pressure monitoring system is NOT a
substitute for manually checking tire pressure. The tire pressure
should be checked periodically (at least monthly) using a tire gauge.
SeeInflating Your Tiresin this chapter. Failure to properly maintain
your tire pressure could increase the risk of tire failure, loss of control,
vehicle rollover and personal injury.
Each tire, including the spare (if provided), should be checked
monthly when cold and inflated to the inflation pressure
recommended by the vehicle manufacturer on the vehicle
placard or tire inflation pressure label. (If your vehicle has tires of a
different size than the size indicated on the vehicle placard or tire
inflation pressure label, you should determine the proper tire inflation
pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire
pressure monitoring system (TPMS) that illuminates a low tire pressure
telltale when one or more of your tires is significantly under-inflated.
Accordingly, when the low tire pressure telltale illuminates, you should
stop and check your tires as soon as possible, and inflate them to the
proper pressure. Driving on a significantly under-inflated tire causes the
tire to overheat and can lead to tire failure. Under-inflation also reduces
fuel efficiency and tire tread life, and may affect the vehicle’s handling
and stopping ability.
Please note that the TPMS is not a substitute for proper tire
maintenance, and it is the driver’s responsibility to maintain correct tire
pressure, even if under-inflation has not reached the level to trigger
illumination of the TPMS low tire pressure telltale.
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Low tire
pressure
warning lightPossible cause Customer action required
Flashing
warning lightSpare tire in use Repair the damaged road wheel
and tire and reinstall it on the
vehicle to restore system function.
For a description on how the
system functions, seeWhen your
temporary spare tire is installed
in this section.
Tire pressure
monitoring
system
malfunctionIf the tires are properly inflated
and the spare tire is not in use but
the light remains on, contact your
authorized dealer as soon as
possible.
When inflating your tires
When putting air into your tires (such as at a gas station or in your
garage), the tire pressure monitoring system may not respond
immediately to the air added to your tires.
It may take up to two minutes of driving over 20 mph (32 km/h) for the
light to turn off after you have filled your tires to the recommended
inflation pressure.
How temperature affects your tire pressure
The tire pressure monitoring system monitors tire pressure in each
pneumatic tire. While driving in a normal manner, a typical passenger
tire inflation pressure may increase approximately 2 to 4 psi (14 to
28 kPa) from a cold start situation. If the vehicle is stationary overnight
with the outside temperature significantly lower than the daytime
temperature, the tire pressure may decrease approximately 3 psi
(21 kPa) for a drop of 30°F (17°C) in ambient temperature. This lower
pressure value may be detected by the system as being significantly
lower than the recommended inflation pressure and activate the system
warning light for low tire pressure. If the low tire pressure warning light
is on, visually check each tire to verify that no tire is flat. If one or more
tires are flat, repair as necessary. Check air pressure in the road tires.
If any tire is under-inflated, carefully drive the vehicle to the nearest
location where air can be added to the tires. Inflate all the tires to the
recommended inflation pressure.
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