tires Lexus IS300 2005 Basic Functions / LEXUS 2005 IS300 (OM53489U) Owner's Guide

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You should check the tire inflation pressure every two
weeks, or at least once a month. And do not forget the
spare. The inflation pressure for the spare tire should be
adjusted according to the conditions in the table on page
344, 346 or 347.
The following instructions for checking tire inflation
pressure should be observed:
 The inflation pressure should be checked only
when the tires are cold. If your vehicle has been
parked for at least 3 hours and has not been driven for
more than 1.5 km or 1 mile since, you will get an accurate cold tire inflation pressure reading.
 Always use a tire pressure gauge. The appearance
of the tire can be misleading. Besides, tire inflation
pressures that are even just a few pounds off can
degrade ride and handling.
 Do not bleed or reduce tire inflation pressure after
driving. It is normal for the tire inflation pressure to be
higher after driving.
 Never exceed the vehicle capacity weight.
Passengers and luggage weight should be located so that the vehicle is balanced.
CAUTION
The inflation pressure for the compact spare tire
must be 420 kPa (4.3 kgf/cm2, 4.2 bar, 60 psi).
Inspection and adjustment procedure
SV63010

1Tire valve
2Tire pressure gauge
1. Remove the tire valve cap.
2. Press the tip of the tire pressure gauge to the tire
valve.
3. Read the pressure using the graduations of the
gauge.
4. In case the tire inflation pressure is not within the
prescribed range, insert the compressed air from the
valve. In case of applying too much air, press the center
of the valve and release the air to adjust.
5. After completing the tire inflation pressure
measurement and adjustment, apply soapy water to the
valve and check for leakage.
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6. Install the tire valve cap.
If a gauge and air pump are not available, have your
vehicle checked by your Lexus dealer.
CAUTION
Be sure to reinstall the tire valve caps. Without the
valve caps, dirt or moisture could get into the
valve core and cause air leakage. If the caps have
been lost, have new ones put on as soon as
possible.
Incorrect tire inflation pressure may waste fuel, reduce
the comfort of driving, reduce tire life and make your
vehicle less safe to drive.
If a tire needs frequent refilling, have it checked by your
Lexus dealer.
CAUTION
Keep your tires properly inflated. Otherwise, the
following conditions may occur and cause an
accident resulting in death or serious injuries.
Low tire pressure (underinflation)Ð
Excessive wear
 Uneven wear
 Poor handling
 Possibility of blowouts from an overheated tire
 Poor sealing of the tire bead
 Wheel deformation and/or tire separation
 A greater possibility of tire damage from road
hazards
High tire pressure (overinflation)Ð
 Poor handling
 Excessive wear
 Uneven wear
 A greater possibility of tire damage from road
hazards
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1Tire size: For details, see ªTire sizeº on page
358.
2DOT and Tire Identification Number (TIN): For
details, see ªDOT and Tire Identification Number
(TIN)º on page 358.
3Maximum cold tire inflation pressure: This
means the pressure to which a tire may be
inflated. For recommended cold tire inflation
pressure, see ªSpecificationsº on page 344, 346
or 347.
4Load limit at maximum cold tire inflation
pressure: For details, see ªChecking and
replacing tiresº on page 368.
5Turning indicator: Some vehicles are equipped
with directional tires. For details, see ªRotating
tiresº on page 366 or 367.
6Tire ply composition and materials : Plies
mean a layer of rubber±coated parallel cords.
Cords mean the strands forming the plies in the
tire.
7Uniform tire quality grading: For details, see
ªUniform tire quality gradingº that follows.
8Location of tread wear indicators: For details,
see ªChecking and replacing tiresº on page 368.
9ªTUBELESSº or ªTUBE TYPEº: A tubeless tire
does not have a tube inside the tire and air is
directly filled in the tire. A tube type tire has a tube
inside the tire and the tube maintains the air
pressure.
10Radial tires or bias±ply tires: A radial tire has
ªRADIALº on the sidewall. A tire not marked with
ªRADIALº is a bias±ply tire.
11Summer tire or all season tire: An all season
tire has ªM+Sº on the sidewall. The tire not
marked with ªM+Sº is a summer tire. For details,
see ªTypes of tiresº on page 365.
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1ªTEMPORARY USE ONLYº: A compact spare
tire is identified by the phrase ªTEMPORARY
USE ONLYº molded into its sidewall. This tire is
designed for temporary emergency use only. For
details, see ªCompact spare tireº on page 287.
2Tire size: For details, see ªTire sizeº on page
358.
3DOT and Tire Identification Number (TIN): For
details, see ªDOT and Tire Identification Number
(TIN)º on page 358.
4Location of tread wear indicators: For details,
see ªChecking and replacing tiresº on page 368.
5Load limit at maximum cold tire inflation
pressure: For details, see ªChecking and
replacing tiresº on page 368.
6Maximum cold tire inflation pressure: This
means the pressure to which a tire may be
inflated. For recommended cold tire inflation
pressure, see ªSpecificationsº on page 344, 346
or 347.
7Tire ply composition and materials : Plies
mean a layer of rubber±coated parallel cords.
Cords mean the strands forming the plies in the
tire.
8ªTUBELESSº or ªTUBE TYPEº: A tubeless tire
does not have a tube inside the tire and air is
directly filled in the tire. A tube type tire has a tube
inside the tire and the tube maintains the air
pressure.
9Radial tires or bias±ply tires: A radial tire has
ªRADIALº on the sidewall. A tire not marked with
ªRADIALº is a bias±ply tire.
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Name of each section of tire
SV63016

1Bead
2Sidewall
3Shoulder
4Tread
5Belt
6Inner liner
7Reinforcing rubber
8Carcass
9Rim lines
10Bead wires
11Chafer
Uniform tire quality grading
This information has been prepared in accordance
with regulations issued by the National Highway
Traffic Safety Administration of the U.S. Department
of Transportation. It provides the purchasers and/or
prospective purchasers of Lexus vehicles with
information on uniform tire quality grading.
Your Lexus dealer will help answer any questions
you may have as you read this information.
DOT quality grades ± All passenger vehicle tires
must conform to Federal Safety Requirements in
addition to these grades. Quality grades can be
found where applicable on the tire sidewall between
tread shoulder and maximum section width. For
example: T readwear 200 Traction AA Temperature A
Tread wear ± 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 a 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.
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Traction AA, A, B, C ± The traction grades, from highest
to lowest, are AA, A, B and C, and they 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.
Warning: The traction grade assigned to this tire is
based on braking (straight ahead) traction tests and
does not include cornering (turning) traction.
Temperature A, B, C ± 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. Sustained high
temperature can cause the material of the tire to
degenerate and reduce tire life, and excessive
temperature can lead to sudden tire failure. The grade
C corresponds to a level of performance which all
passenger car tires must meet under the Federal Motor
Vehicle Safety Standard No. 109. Grades B and A
represent higher levels of performance on the laboratory
test wheel than the minimum required by law.
Warning: The temperature grades for this tire are
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
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TYPES OF TIRES
Determine what kind of tires your vehicle is originally
equipped with.
1. Summer tires
Summer tires are high±speed capability tires best suited
to highway driving under dry conditions.
Since summer tires do not have the same traction
performance as snow tires, summer tires are
inadequate for driving on snow±covered or icy roads.
For driving on snow±covered or icy roads, we
recommend using snow tires. If installing snow tires, be
sure to replace all four tires.
2. All season tires
All season tires are designed to provide better traction
in snow and to be adequate for driving in most winter
conditions, as well as for use all year round.
All season tires, however, do not have adequate traction
performance compared with snow tires in heavy or loose
snow. Also, all season tires fall short in acceleration and
handling performance compared with summer tires in
highway driving.
The details about how to distinguish summer tires from
all season tires are described on page 354.
CAUTION
 Do not mix summer and all season tires on your
vehicle as this can cause dangerous handling
characteristics, resulting in loss of control.
 Do not use tires other than the manufacturer's
designated tires, and never mix tires or wheels
of the sizes different from the originals as this
can cause dangerous handling characteristics,
resulting in loss of control.
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ROTATING TIRES (Sedan)
SV63007

Pattern A
SV63008

Pattern B
To equalize tire wear and help extend tire life, Lexus
recommends that you rotate your tires according to
the maintenance schedule. (For scheduled
maintenance information, please refer to the
ªOwner's Manual Supplement/Scheduled
Maintenanceº.) However, the most appropriate
timing for tire rotation may vary according to your
driving habits and road surface conditions.
The wheel assemblies must be rotated as illustrated
above.
Pattern A: Except vehicles with the P205/55 R16 tires
sold in Canada.
Pattern B: Vehicles with the P205/55R16 tires sold in
Canada.
When rotating tires, check for uneven wear and
damage. Abnormal wear is usually caused by incorrect
tire pressure, improper wheel alignment, out±of balance
wheels, or severe braking.
Before storing radial, snow or studded tires, mark the
direction of rotation and be sure to install them in the
same direction when using them again. Tires should be
stored in a cool dry place.
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ROTATING TIRES (SportCross)
SV63007

With the P205/55R16 or 215/45ZR17 tires
To equalize tire wear and help extend tire life, Lexus
recommends that you rotate your tires according to
the maintenance schedule. (For scheduled
maintenance information, please refer to the
ªOwner's Manual Supplement/Scheduled
Maintenanceº.) However, the most appropriate
timing for tire rotation may vary according to your
driving habits and road surface conditions.
The wheel assemblies must be rotated as illustrated
above.
When rotating tires, check for uneven wear and
damage. Abnormal wear is usually caused by incorrect
tire pressure, improper wheel alignment, out±of balance
wheels, or severe braking. Before storing radial, snow or studded tires, mark the
direction of rotation and be sure to install them in the
same direction when using them again. Tires should be
stored in a cool dry place.
SV63009

With the 215/45ZR17 tires for front and the
225/45ZR17 tires for rear
Do not perform rotation of the tires, from front to rear
or from left to right, or using the spare tire,
performing such tire rotation may result in the tires
interfering with the body or in uneven wear of the
tires, so that steerability of the vehicle is impaired.
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CHECKING AND REPLACING TIRES
When to replace your tires
SV63006

1New tread 2Tread wear indicator
3Worn tread
Replace the tires when the tread wear indicators
show. The location of tread wear indicators is shown
by the ªTWIº or ª
Dº marks, etc., molded on the
sidewall of each tire.
The tires on your Lexus have built±in tread wear
indicators to help you know when the tires need
replacement. When the tread depth wears to 1.6 mm
(0.06 in.) or less, the indicators will appear. If you can see
the indicators in two or more adjacent grooves, the tire
should be replaced. Vehicles equipped with 215/45ZR17 or 225/45ZR17
tires:
Your Lexus has been fitted with specially
developed tires which provide exceptional dynamic
performance under general road conditions. However
your riding comfort may worsen a little and road noise
may increase during driving. You may also notice that
your tires will wear more rapidly and tire grip
performance will be reduced on the snowy and/or icy
roads when compared to standard tires. Be sure to have
snow tires or tire chains on the snowy and/or icy roads
and drive carefully with the speed appropriate for road
conditions.
NOTICE
Low profile tire like 215/45ZR17 or 225/45ZR17 may have greater damage than usual tires to its
tire wheel when receiving impact from the roadsurface. Therefore, pay attention to the
followings.
Be sure to use with proper tire inflationpressure. If the tire pressure is low, the tire mayhave a greater damage. For detailed information
about tire inflation pressure, see page 344 or 346.
Avoid driving onto high, sharp±edged objectsand other road hazards. Failure to do so can
lead to severe tire damage.
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