2003 Lexus IS300 Basic Functions / LEXUS 2003 IS300 OWNER'S MANUAL (OM53439U)

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CAUTION
Keep your tire pressure at the proper level. Otherwise,
the following conditions may occur and cause an
accident.
Low tire pressure (underinflation)Ð
Excessive wear
 Uneven wear
 Poor handling
 Possibility of blowouts from overheated tire
 Poor sealing of the tire bead
 Wheel deformation and/or tire separation
High tire pressure (overinflation)Ð
 Poor handling
 Excessive wear at the center of the tire tread
 A greater possibility of tire damage from road
hazards
The following instructions for checking tire pressure should be
observed:
The 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 pressure reading.
 Always use a tire pressure gauge. The appearance of the
tire can be misleading. Besides, tire pressures that are
even just a few pounds off can degrade ride and handling.
 Do not bleed or reduce tire pressure after driving. It is
normal for the tire pressure to be higher after driving.
 Never exceed the vehicle capacity weight. The
passengers and luggage weight should be located so that
the vehicle is balanced.
 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.
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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 ºOwner'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 ºOwner'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 the tread wear indicators is shown by the
ºTWIº or º
Dº marks 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 whenreceiving impact from the road surface. Therefore, payattention to the followings.
Be sure to use with proper tire pressure. If the tirepressure is low, the tire may have a greater damage.For detailed information about tire pressure, seepage 326 or 327.
Avoid driving onto high, sharp±edged objects andother road hazards. Failure to do so can lead tosevere tire damage.
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.
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336If 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 an air loss occurs while driving, do not continue driving with
a deflated tire. 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 also applies to the spare tire and tires stored for future
use.
Uniform tire quality grading
This information has been prepared in accordance with
regulations
issued by the National Highway T raffic 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: Treadwear 200
Traction AA Temperature A
Treadwear ± 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.
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.
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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.
Tire selection
When replacing a tire, use a tire of the same size and
construction, and the same or g reater load capacity 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.
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.
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INSTALLING SNOW TIRES ANDCHAINS
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.
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 120 km/h (75 mph) with any type of
snow tires.
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Tire chain selection
63L009a

1Side chain 2Cross chain
Use the tire chains of correct size.
For 225/45ZR17 tires, use the following type chains.mm (in.)
A: Diameter of side chain 3.0 (0.12)
B: Diameter of cross chain 4.0 (0.16)
For P205/55R16 or 215/45ZR17 tires, use SAE Class ºSº type
radial tire chains, with the exception of radial cable chains or
V±bar type chains.
Regulations regarding the use of tire chains vary
according to location or type of road. Always check the
local regulations before installing chains.
NOTICE
If the wrong combination of tire and chain is used, the chains could damage the vehicle body.
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 ± 1.0 km (1/4 ± 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 the curves to
avoid losing control of the vehicle, it may cause an
accident.
2003 IS300 from Aug. '02 Prod. (OM53439U)