CHASSIS
360
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.
04 06.30
CHASSIS
361
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.
04 06.30
CHASSIS
365
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.
04 06.30
CHASSIS
366
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.
04 06.30
CHASSIS
367
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.
04 06.30
CHASSIS
368
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.
04 06.30
CHASSIS
369
The effectiveness of snow tires is lost if the tread
wears down below 4 mm (0.16 in.).
If you have tire damage such as cuts, splits, cracks
deep enough to expose the fabric, or bulges
indicating internal damage, the tire should be
replaced.
If a tire often goes flat or cannot be properly repaired due
to the size or location of a cut or other damage, it should
be replaced. If you are not sure, consult with your Lexus
dealer.
If air loss occurs while driving, do not continue driving.
Driving even a short distance can damage a tire beyond
repair.
Any tires which are over 6 years old must be
checked by a qualified technician even if damage is
not obvious.
Tires deteriorate with age even if they have never or
seldom been used.
This applies also to the spare tire and tires stored for
future use.Tire selection
When replacing a tire, use a tire of the same size and
construction, and the same or greater maximum
load as the originally installed tires.
Using any other size or type of tire may seriously affect
handling, ride, speedometer/odometer calibration,
ground clearance, and clearance between the body and
tires or snow chains.
Check that the maximum load of the replaced tire is
greater than 1/2 of the Gross Axle Weight Ratings
(GAWR) of either the front axle or the rear axle,
whichever is greater. As for the maximum load of the tire,
see the load limit at maximum cold tire inflation pressure
mentioned on the sidewall of the tire, and as for the
Gross Axle Weight Ratings (GAWR), see the
Certification Label. For details about the Certification
Label and sidewall of the tire, see pages 316 and 354.
04 06.30
CHASSIS
370
CAUTION
Observe the following instructions. Otherwise, an
accident may occur resulting in death or serious
injuries.
Do not mix radial, bias belted, or bias±ply tires
on your vehicle, as this may cause dangerous
handling characteristics resulting in loss of
control.
Do not use tires other than the manufacturer's
recommended size, as this may cause
dangerous handling characteristics resulting in
loss of control.
If you need to change from conventional tires to radial
tires or vice versa, replace them as a set.
INSTALLING SNOW TIRES AND
CHAINS
When to use snow tires or chains
Snow tires or chains are recommended when driving on
snow or ice.
On wet or dry roads, conventional or radial tires provide better
traction than snow or studded tires.
Snow tire selection
If you need snow tires, select tires of the same size,
construction and load capacity as the originally installed
tires.
Do not use tires other than stated above. Since your vehicle
has radial tires as original equipment, make sure your snow
tires also have radial construction. Do not install studded tires
without first checking local regulations for possible restrictions.
CAUTION
Observe the following instructions. Otherwise, an
accident may occur resulting in death or serious
injuries.
Do not use snow tires other than the manufacturer's
recommended size, as this may cause dangerous
handling characteristics resulting in loss of control.
04 06.30