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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 Ð All passenger car 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: Treadwear 200 Traction AA
Temperature A
Treadwear Ð 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 Ð 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 AA, A, B, C Ð 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 Ð 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 grade for this tire
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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Tire related termMeaning
Production options
weightthe combined weight of those installed regular production options weighing over
2.3 kg (5 lb.) 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
Vehicle capacity
weight
(Total load capacity)the rated cargo and luggage load plus 68 kg (150 lb.) times the vehicle's
designated seating capacity
Intended outboard
sidewall(a) the sidewall that contains a whitewall, bears white lettering or bears
manufacturer, brand, and/or model name molding that is higher or deeper
than the same molding on the other sidewall of the tire, or
(b) the outward facing sidewall of an asymmetrical tire that has a particular side
that must always face outward when mounted on a vehicle
Occupant distributiondistribution of occupants in a vehicle as specified in the third column of Table 1
that follows
Recommended
inflation pressurecold tire inflation pressure recommended by a manufacturer
Rima metal support for a tire or a tire and tube assembly upon which the tire beads
are seated
Rim diameter (Wheel
diameter)nominal diameter of the bead seat
Rim size designationrim diameter and width
Rim type designationthe industry of manufacturer's designation for a rim by style or code
Rim widthnominal distance between rim flanges
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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 561.
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.
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ROTATING 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 Owner'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.
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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. Also, all the tires must be the same brand and have
the same tread patterns.
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.
Do not use snow tires of different brands, sizes,
construction or tread patterns, as this may cause
dangerous handling characteristics resulting in loss
of control.
Snow tire installation
Snow tires should be installed on all wheels.
Installing snow tires on the rear wheels only can lead to an
excessive difference in road grip capability between the front
and rear tires which could cause loss of vehicle control.
CAUTION
Do not drive with the snow tires incorrectly inflated.
Never drive over 105 km/h (65 mph) with any type of
snow tires.
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Chain installation
Install the chains on the rear tires as tightly as possible.
Do not use tire chains on the front tires. Retighten chains
after driving 0.5 Ð 1.0 km (1/4 Ð 1/2 mile).
When installing chains on your tires, carefully follow the
instructions of the chain manufacturer.CAUTION
Do not exceed 50 km/h (30 mph) or the chain
manufacturer's recommended speed limit,
whichever is lower.
Drive carefully avoiding bumps, holes, and sharp
turns, which may cause the vehicle to bounce.
Avoid sharp turns or locked-wheel braking, as use of
chains may adversely affect vehicle handling.
When driving with chains installed, be sure to drive
carefully. Slow down before entering curves to avoid
losing control of the vehicle. Otherwise an accident
may occur.
NOTICE
When jacking up or installing tire chains, be sure to turn
off the rear height control air suspension with the
HEIGHT CONTROL OFFº switch and stop the engine.
Otherwise, the vehicle height may change because of
the automatic leveling function resulting in accident.
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REPLACING WHEELS
When to replace your wheels
If you have wheel damage such as bending, cracks or
heavy corrosion, the wheel should be replaced.
If you fail to replace a damaged wheel, the tire may slip off the
wheel or cause loss of handling control.
Replacement with used wheels is not recommended as they
may have been subjected to rough treatment or high mileage
and could fail without warning. Also, bent wheels which have
been straightened may have hidden structural damage and
therefore should not be used. Never use an inner tube in a
leaking wheel which is designed for a tubeless tire.
Wheel selection
When replacing wheels, care should be taken to ensure
that they are equivalent to those removed in load capacity,
diameter, rim width, and offset.
Correct replacement wheels are available at your Lexus
dealer.
A wheel of a different size or type may adversely affect
handling, wheel and bearing life, brake cooling,
speedometer/odometer calibration, stopping ability, headlight
aim, bumper height, vehicle ground clearance, and tire or snow
chain clearance to the body and chassis.
CAUTION
Observe the following instructions. Otherwise, an
accident may occur resulting in death or serious
injuries.
Do not use wheels other than the manufacturer's
recommended size, as this may cause dangerous
handling characteristics resulting in loss of control.
Do not use wheels of different brands, sizes and
types, as this may cause dangerous handling
characteristics resulting in loss of control.
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ALUMINUM WHEEL PRECAUTIONS
When installing aluminum wheels, check that the wheel nuts
are tight after driving your vehicle the first 1600 km (1000
miles).
If you have rotated, repaired, or changed your tires, check
that the wheel nuts are still tight after driving 1600 km (1000
miles).
When using tire chains, be careful not to damage the
aluminum wheels.
Use only the Lexus wheel nuts and wrench designed for
your aluminum wheels.
When balancing your wheels, use only Lexus balance
weights or equivalent and a plastic or rubber hammer.
As with any wheel, periodically check your aluminum
wheels for damage. If damaged, replace immediately.
SUSPENSION AND CHASSIS
CAUTION
Do not modify the suspension/chassis with lift kits,
spacers, springs, etc. It can cause dangerous handling
characteristics, resulting in loss of control.