Example illustration: Tire inflation pressures forparticular tire sizes
Some tire inflation pressure labels may only
show the rim diameter instead of the entire
tire size, e.g. R 18 or 18".
The rim diameter is part of the tire size as
specified on the tire sidewall (Y page 426).
Example illustration: Tire inflation pressuresspecific to rim diameter
Potential problems associated with
underinflated and overinflated tires
Underinflated tires
GWarning!
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Underinflated tires can
Rcause excessive and uneven tire wear
Radversely affect fuel economy
Rlead to tire failure from being overheated
Radversely affect handling characteristics
Overinflated tires
GWarning!
Follow recommended tire inflation pressures.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Overinflated tires can
Radversely affect handling characteristics
Rcause uneven tire wear
Rbe more prone to damage from road
hazards
Radversely affect ride comfort
Rincrease stopping distance
Checking tire inflation pressure
Safety notes
GWarning!
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver’s door B-pillar. Overloading the tires
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can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
Check the tire inflation pressure at least once
a month.
Check and adjust the tire inflation pressure
when the tires are cold ( Y page 411).
Checking tire inflation pressure
manually
Follow the steps below to achieve correct tire
inflation pressure:
XRemove the cap from the valve on one tire.XFirmly press a tire gauge onto the valve.XRead the tire inflation pressure on the tire
gauge and check against the
recommended tire inflation pressure on the
Tire and Loading Information placard on the
driver’s door B-pillar ( Y page 418). If
necessary, add air to achieve the
recommended tire inflation pressure.XIf you have overfilled the tire, release tire
inflation pressure by pushing the metal
stem of the valve with e.g. a tip of a pen.
Then recheck the tire inflation pressure
with the tire gauge.XInstall the valve cap.XRepeat this procedure for each tire.
Advanced Tire Pressure Monitoring
System (Advanced TPMS)
Your vehicle is equipped with the Advanced
Tire Pressure Monitoring System (Advanced
TPMS). It measures the tire inflation pressure
in the vehicle’s tires and issues warnings in
case of pressure loss in one or more of the
tires.
The TPMS is equipped with a combination low
tire pressure/ TPMS malfunction telltale
(USA) or a low tire pressure telltale (Canada)
in the instrument cluster. Depending on how
the telltale illuminates, it indicates a low tire
pressure condition or a malfunction in the
TPMS system itself:
R If the telltale illuminates continuously, one
or more of your tires is significantly
underinflated. There is no malfunction in
the TPMS.
R USA only: If the telltale flashes for 60
seconds and then stays illuminated, the
TPMS system itself is not operating
properly.
The TPMS only functions on wheels that are
equipped with the proper electronic sensors.GWarning!
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to the
Tire and Loading Information placard or the
supplemental tire inflation pressure
information on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g. tire
blowout caused by a foreign object). In this
case bring the vehicle to a halt by carefully
applying the brakes and avoiding abrupt
steering maneuvers.
GWarning!
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the Tire and Loading
Information placard on the driver’s door B-
pillar or the tire inflation pressure label on the
inside of the fuel filler flap. If your vehicle has
tires of a different size than the size indicated
on the Tire and Loading Information placard
or the tire inflation pressure label, you should
determine the proper tire inflation pressure
for those tires.
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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 are significantly underinflated.
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 underinflated tire causes the tire
to overheat and can lead to tire failure.
Underinflation 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 underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the
system detects a malfunction, the telltale will
flash for approximately 1 minute and then
remain continuously illuminated. This
sequence will continue upon subsequent
vehicle start-ups as long as the malfunction
exists. When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of
reasons, including the installation of
incompatible replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on your
vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to
continue to function properly.
iUSA only:
If a condition causing the TPMS to
malfunction develops, it may take up to
10 minutes for the system to signal a
malfunction using the TPMS telltale
flashing and illumination sequence.
The telltale extinguishes after a few
minutes driving if the malfunction has been
corrected.
Tire pressure inquiries are made using the
multifunction display. The current tire
inflation pressure for each tire appears in the
multifunction display after a few minutes of
driving.
iPossible differences between the
readings of a tire pressure gauge of an air
hose, e.g. gas station equipment, and the
vehicle’s control system can occur. The tire
pressure displayed by the control system
apply to sea level. In high-altitude
locations, the reading on a tire pressure
gauge will be higher than the reading issued
by the vehicle’s control system. Do not
reduce the tire inflation pressure under
such circumstances.
XSwitch on the ignition.XPress button = or ; on the
multifunction steering wheel to select the
Service menu (Y page 233).
XPress button 9 or : to select Tire
Press..
XPress button a.
The current inflation pressure for each tire
appears in the multifunction display.
Example illustration
When the vehicle has been parked for longer
than 20 minutes, the message Tire
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driver’s door B-pillar. Some vehicles may have
supplemental tire inflation pressure
information for driving at high speeds or for
vehicle loads less than the maximum loaded
vehicle condition. If such information is
provided, it can be found on the inside of the
fuel filler flap.
XUsing the Tire and Loading Information
placard on the driver’s door B-pillar
(Y page 418) or the supplemental tire
inflation pressure information on the inside
of the fuel filler flap, make sure the tire
inflation pressure of all four tires is correct.
XSwitch on the ignition.XPress button = or ; on the
multifunction steering wheel to select the
Service menu.
XPress button 9 or : on the
multifunction steering wheel to select
Tire Press..
XPress button a.
The current inflation pressure for each tire
appears in the multifunction display or the
following message appears in the
multifunction display:
Tire Pressure
Displayed After Driving
A Few Minutes
XPress button :.
The following message appears in the
multifunction display:
Use Current
Pressures As New
Reference Values
Press 'OK' to Confirm
XPress button a.
The following message appears in the
multifunction display:
Tire Pressure Monitor
Reactivated
After driving a few minutes the system
verifies that the current tire inflation
pressures are within the system’s specified
range. Afterwards the current tire inflation
pressures are accepted as reference values
and then monitored.
XIf you wish to cancel: Press button %.
or
XPress button 9 to exit the menu screen.
iWhen the wheel positions have been
changed, the inflation pressure of a tire
may be displayed for the wrong position
temporarily. After driving for a few minutes,
the inflation pressure will be shown for the
correct position.
Maximum tire inflation pressure
GWarning!
Never exceed the maximum tire inflation
pressure. Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
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This is the maximum permissible tire inflation
pressure : for the tire.
Always follow the recommended tire inflation
pressure (Y page 411) for proper tire
inflation.
Loading the vehicle
Two labels on your vehicle show how much
weight it may properly carry.
(1)The Tire and Loading Information placard
can be found on the driver’s door
B-pillar. This placard tells you important
information about the number of people
that can be in the vehicle and the total
weight that can be carried in the vehicle.
It also contains information on the proper
size and recommended tire inflation
pressures for the original equipment tires
on your vehicle.
(2)The certification label, also found on the
driver’s door B-pillar. It tells you about the
gross weight capacity of your vehicle,
called the Gross Vehicle Weight Rating
(GVWR). The GVWR includes the weight
of the vehicle, all occupants, fuel and
cargo. The certification label also tells
you about the front and rear axle weight
capacity, called the Gross Axle Weight
Rating (GAWR).
The GAWR is the total allowable weight
that can be carried by a single axle (front
or rear). Never exceed the GVWR or
GAWR for either the front axle or rear
axle.
:Driver’s door B-pillar
Following is a discussion on how to work with
the information contained on the Tire and
Loading Information placard with regards to
loading your vehicle.
Tire and Loading Information
GWarning!
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver’s door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
Tire and Loading Information placard
iData shown on Tire and Loading
Information placard example are for
illustration purposes only. Load limit data
are specific to each vehicle and may vary
from data shown in the following
illustration. Refer to Tire and Loading
Information placard on vehicle for actual
data specific to your vehicle.
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Storing tires
! Keep unmounted tires in a cool, dry place
with as little exposure to light as possible.
Protect tires from contact with oil, grease
and fuels.
Cleaning tires
! Never use a round nozzle to power wash
tires. The intense jet of water can result in
damage to the tire.
Always replace a damaged tire.
Uniform Tire Quality Grading
Standards
The Uniform Tire Quality Grading is a U.S.
Government requirement designed to give
drivers consistent and reliable information
regarding tire performance. Tire
manufacturers are required to grade tires
based on three performance factors:
treadwear :, traction ;, and temperature
resistance =. Although not a Government of
Canada requirement, all tires made for sale in
North America have these grades branded on
the sidewall.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
Quality grades can be found, where
applicable, on the tire sidewall between tread
shoulder and maximum section width. For
example:
TreadwearTractionTemperature200AAA
All passenger car tires must conform to
federal safety requirements in addition to
these 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
U.S. 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.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm due to variations in driving habits,
service practices and differences in road
characteristics and climate.
Traction
GWarning!
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those 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.
GWarning!
If ice has formed on the road, tire traction will
be substantially reduced. Under such weather
conditions, drive, steer and brake with
extreme caution.
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Tire type code
Tire type code ? may, at the option of the
manufacturer, be used as a descriptive code
for identifying significant characteristics of
the tire.
Date of manufacture
The date of manufacture A identifies the
week and year of manufacture.
The first two figures identify the week,
starting with “01” to represent the first full
week of the calendar year. The second two
figures represent the year.
For example, “3208” represents the 32nd
week of 2008.
Tire ply material
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
This marking tells you about the type of cord
and number of plies in the sidewall : and
under the tread ;.
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power seats,
radio, and heater, to the extent that these
items are available as factory-installed
equipment (whether installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire. Air
pressure is expressed in pounds per square
inch (psi), kilopascal (kPa), or bar.
Aspect ratio
Dimensional relationship between tire
section height and section width expressed
in percentage.
Bar
Metric unit for air pressure. There are
14.5038 pounds per square inch (psi) to
1 bar; there are 100 kilopascals (kPa) to 1 bar.
Bead
The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle has
been sitting for at least 3 hours or driven no
more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with standard
equipment including the maximum capacity
of fuel, oil, and coolant, and, if so equipped,
air conditioning and additional optional
equipment, but without passengers and
cargo.
DOT (Department of Transportation)
A tire branding symbol which denotes the tire
meets requirements of the U.S. Department
of Transportation.
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GAWR (Gross Axle Weight Rating)
The GAWR is the maximum permissible axle
weight. The gross vehicle weight on each axle
must never exceed the GAWR for the front
and rear axle indicated on the certification
label located on the driver’s door B-pillar.
GVW (Gross Vehicle Weight)
The GVW comprises the weight of the vehicle
including fuel, tools, spare wheel, installed
accessories, passengers and cargo and, if
applicable, trailer tongue load. The GVW must
never exceed the GVWR indicated on the
certification label located on the driver’s door
B-pillar.
GVWR (Gross Vehicle Weight Rating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passengers,
fuel, and cargo and, if applicable, trailer
tongue load). It is indicated on the
certification label located on the driver’s door
B-pillar.
Kilopascal (kPa)
Metric unit for air pressure. There are 6.9 kPa
to 1 psi; another metric unit for air pressure
is bar. There are 100 kilopascals (kPa) to
1 bar.
Load index
Numerical code associated with the
maximum load a tire can support.
Maximum load rating
The maximum load in kilograms and pounds
that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
total load limit, and production options
weight.
Maximum permissible tire inflation
pressure
This number is the greatest amount of air
pressure that should ever be put in the tire.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by 68 kilograms
(150 lb).
Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (Pounds per square inch)
A standard unit of measure for air pressure.
Recommended tire inflation pressure
The recommended tire inflation pressure for
normal driving conditions is listed on the Tire
and Loading Information placard located on
the driver’s door B-pillar. It provides best
handling, tread life and riding comfort.
Supplemental information pertaining to
special driving situations can be found on the
tire inflation pressure label on the inside of
the fuel filler flap.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
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