2. Economy—
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under-inflation, also increases
tire rolling resistance and results in higher fuel consump-
tion.
3. Ride Comfort and Vehicle Stability—
Proper tire inflation contributes to a comfortable ride.
Over-inflation produces a jarring and uncomfortable
ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed either on
the face of the driver’s door or on the driver’s side
B-pillar.
Some vehicles may have supplemental tire pressure
information for vehicle loads that are less than themaximum loaded vehicle condition. These pressure con-
ditions will be found in the “Supplemental Tire Pressure
Information” section of this manual.
The pressure should be checked and adjusted as well as
inspecting for signs of tire wear or visible damage at least
once a month. Use a good quality pocket-type gauge to
Tire Placard Location
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check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under-inflated.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap (if equipped). This
will prevent moisture and dirt from entering the
valve stem, which could damage the valve stem.
Inflation pressures specified on the placard are always
“cold tire inflation pressure.” Cold tire inflation pressure
is defined as the tire pressure after the vehicle has not
been driven for at least three hours, or driven less than 1
mi (1 km) after a three hour period. The cold tire inflation
pressure must not exceed the maximum inflation pres-
sure molded into the tire sidewall.Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.
Tire pressures change by approximately 1 psi (7 kPa) per
12° F (7° C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the Winter.
Example: If garage temperature = 68°F (20°C) and the
outside temperature = 32°F (0°C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12°F (7°C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
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Tire Pressures for High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
loading may be required for high-speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maxi-
mum load is dangerous. The added strain on your
tires could cause them to fail. You could have a
serious accident. Don’t drive a vehicle loaded to the
maximum capacity at continuous speeds above 75
mph (120 km/h).
Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial ply tires in sets of four (or six, in case
of trucks with dual rear wheels). Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized tire dealer for radial tire repairs.
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Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed. (Refer to the paragraph on
“Tread Wear Indicators”). Refer to the “Tire and Loading
Information” placard for the size designation of your tire.
The service description and load identification will be
found on the original equipment tire. Failure to use
equivalent replacement tires may adversely affect the
safety, handling, and ride of your vehicle. We recommend
that you contact your original equipment or an autho-
rized tire dealer with any questions you may have on tire
specifications or capability.WARNING!
•Do not use a tire, wheel size or rating other than that
specified for your vehicle. Some combinations of
unapproved tires and wheels may change suspension
dimensions and performance characteristics, result-
ing in changes to steering, handling, and braking of
your vehicle. This can cause unpredictable handling
and stress to steering and suspension components.
You could lose control and have an accident resulting
in serious injury or death. Use only the tire and wheel
sizes with load ratings approved for your vehicle.
•Never use a tire with a smaller load index or capacity
than what was originally equipped on your vehicle.
Using a tire with a smaller load index could result in
tire overloading and failure. You could lose control
and have an accident.
•Failure to equip your vehicle with tires having ad-
equate speed capability can result in sudden tire
failure and loss of vehicle control.
342 STARTING AND OPERATING
TIRE PRESSURE MONITOR SYSTEM (TPMS) — IF
EQUIPPED
•
The Tire Pressure Monitor System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold placard pressure.
•The tire pressure will vary with temperature by about
1 psi (6.9 kPa) for every 12°F (6.5°C). This means that
when the outside temperature decreases, the tire pres-
sure will decrease. Tire pressure should always be set
based on cold inflation tire pressure. This is defined as
the tire pressure after the vehicle has not been driven
for at least three hours, or driven less than 1 mi (1 km)
after a three hour period. The cold tire inflation
pressure must not exceed the maximum inflation
pressure molded into the tire sidewall. Refer to the
“Tires – General Information” in this section for infor-
mation on how to properly inflate the vehicle’s tires.The tire pressure will also increase as the vehicle is
driven - this is normal and there should be no adjust-
ment for this increased pressure.
•The TPMS will warn the driver of a low tire pressure
if the tire pressure falls below the low-pressure warn-
ing limit for any reason, including low temperature
effects and natural pressure loss through the tire.
•The TPMS will continue to warn the driver of low tire
pressure as long as the condition exists, and will not
turn off until the tire pressure is at or above the
recommended cold placard pressure. Once the low tire
pressure warning (Tire Pressure Monitoring Telltale
Light) illuminates, you must increase the tire pressure
to the recommended cold placard pressure in order for
the Tire Pressure Monitoring Telltale Light to turn off.
The system will automatically update and the Tire
Pressure Monitoring Telltale Light will turn off once
the system receives the updated tire pressures. The
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