
under-inflation of the tires, improper tires (load range, size, or type), or
vehicle modifications such as lift-kits. In the event that your vehicle
experiences shimmy, you should slowly reduce speed by either lifting off
the accelerator pedal or lightly applying the brakes. The shimmy will
cease as the vehicle speed decreases.
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
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.
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Note:Some spare tires operate at a higher inflation pressure than the
other tires. For T-type/mini-spare tires (see theDissimilar spare
tire/wheel informationsection for description): Store and maintain at
60 psi (4.15 bar). For full-size and dissimilar spare tires (see the
Dissimilar 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 inflation information
All tires with Steel Carcass Plies (if equipped):
This type of tire utilizes steel cords in the sidewalls. As such, they
cannot be treated like normal light truck tires. Tire service, including
adjusting tire pressure, must be performed by personnel trained,
supervised and equipped according to Federal Occupational Safety and
Health Administration (OSHA) regulations. For example, during any
procedure involving tire inflation, the technician or individual must
utilize a remote inflation device, and ensure that all persons are clear of
the trajectory area.
WARNING:An inflated tire and rim can be very dangerous if
improperly used, serviced or maintained. To reduce the risk of
serious injury, never attempt to re-inflate a tire which has been run flat
or seriously under-inflated without first removing the tire from the
wheel assembly for inspection. Do not attempt to add air to tires or
replace tires or wheels without first taking precautions to protect
persons and property.
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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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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.
Note:Tire Quality Grades do not
apply to this type of tire.
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.
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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. Tire Quality Grades do
not apply to this type of tire.
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 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 edge of
the driver’s door. Refer to the payload description and graphic in the
Vehicle loading – with and without a trailersection.
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Understanding your tire pressure monitoring system (TPMS)
The tire pressure monitoring system measures pressure in your four road
tires and sends the tire pressure readings to your vehicle. The low tire
pressure warning light will turn on if the tire pressure is significantly low.
Once the light is illuminated, your tires are under-inflated and need to be
inflated to the manufacturer’s recommended tire pressure. Even if the
light turns on and a short time later turns off, your tire pressure still
needs to be checked. Visit www.checkmytires.org for additional
information.
When your temporary spare tire is installed
When one of your road tires needs to be replaced with the temporary
spare, the TPMS will continue to identify an issue to remind you that the
damaged road wheel/tire needs to be repaired and put back on your
vehicle.
To restore the full functionality of the tire pressure monitoring system,
have the damaged road wheel/tire repaired and remounted on your
vehicle. For additional information, refer toChanging tires with a
TPMSin this section.
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When you believe your system is not operating properly
The main function of the tire pressure monitoring system is to warn you
when your tires need air. It can also warn you in the event the system is
no longer capable of functioning as intended. Please refer to the
following chart for information concerning your tire pressure monitoring
system:
Low tire
pressure
warning lightPossible cause Customer action required
Solid warning
lightTire(s)
under-inflated1. Make sure tires are at the proper
pressure. SeeInflating your tires
in this chapter.
2. After inflating your tires to the
manufacturer’s recommended
pressure as shown on the Tire
Label (located on the edge of
driver’s door or the B-Pillar), the
vehicle must be driven for at least
two minutes over 20 mph
(32 km/h) before the light turns
off.
Spare tire in use Repair the damaged road wheel/tire
and reinstall it on the vehicle to
restore system functionality. For a
description on how the system
functions, refer toWhen your
temporary spare tire is installed
in this section.
TPMS
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.
Tire rotation
without sensor
trainingOn vehicles with different front and
rear tire pressures, the TPMS must
be retrained following every tire
rotation. SeeTire rotationin this
chapter.
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Low tire
pressure
warning lightPossible cause Customer action required
Flashing
warning lightSpare tire in use Repair the damaged road wheel/tire
and reinstall it on the vehicle to
restore system functionality. For a
description on how the system
functions, refer toWhen your
temporary spare tire is installed
in this section.
TPMS
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 (TPMS) 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 TPMS as being significantly lower
than the recommended inflation pressure and activate the TPMS 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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