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CHASSIS
328± TIRES AND WHEELS (Type C)
Standard tires
Tire sizeP205/55R16 89V
Tire inflation pressure Recommended cold tire inflation pressureFront 230 kPa (2.3 kgf/cm2 or bar, 33 psi)
Rear 230 kPa (2.3 kgf/cm2 or bar, 33 psi)
For sustained high speeds above 160 km/h (100 mph), in countries
where such speeds are permitted by law, add the tire pressure given
below to the front tires and rear tires, but never exceed the maximum
cold tire pressure molded on the tire sidewall.
Sedan 70 kPa (0.8 kgf/cm
2, 0.7 bar, 10 psi)
SportCross Front: 70 kPa (0.8 kgf/cm2, 0.7 bar, 10 psi)
Rear: 90 kPa (0.9 kgf/cm2, 0.9 bar, 15 psi)
Wheel size16 x 6 1/2JJ
Wheel nut torque103 N´m (10.5 kgf´m, 76 ft´lbf.)
Compact spare tire (IS300 sold in Canada only)
Tire sizeT125/70D17 98M
Tire inflation pressure420 kPa (4.2 kgf/cm2 or bar, 60 psi)
Wheel size17 x 4T
Wheel nut torque103 N´m (10.5 kgf´m, 76 ft´lbf.)
NOTE: For complete information on tires (e.g. replacing tires or replacing wheels\
), see ºChecking tire pressureº through ºAluminum
wheel precautionsº on page 331 through 341.
2003 IS300 from Aug. '02 Prod. (OM53439U)
Page 344 of 389
CHASSIS
331
CAUTION
The reservoir may be hot so be careful not to burn
yourself.
NOTICE
Avoid overfilling, or the power steering could bedamaged.
When adding the power steering fluid, avoid spillingit. The generator under the power steering reservoircould be damaged if fluid is spilled on it.
CHECKING TIRE PRESSURE
SV61004
The recommended cold tire pressures, tire size and the
vehicle capacity weight are given on the label.
You should check the tire pressures every two weeks, or at
least once a month. And don't forget the spare! The pressure
for the spare tire should be the same with that for the standard
tire. Incorrect tire 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.
2003 IS300 from Aug. '02 Prod. (OM53439U)
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CHASSIS
334
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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Page 349 of 389

CHASSIS
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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CHASSIS
340
NOTICE
Do not attempt to use a tire chain on the compact sparetire, as it may result in damage to the vehicle as well asthe tire.
REPLACING WHEELS
When to replace your wheels
If you have wheel damage such as bends, cracks or heavy
corrosion, the wheel should be replaced.
If you fail to replace damaged wheels, 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.
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Page 366 of 389
ELECTRICAL COMPONENTS
353
It is a good idea to purchase a set of spare fuses and keep them
in your vehicle for emergencies.
If the new fuse immediately blows out, there is a problem with
the electrical system. Have your Lexus dealer correct it as
soon as possible.
CAUTION
Never use a fuse with a higher amperage rating, or any
other object, in place of a fuse. This may cause
extensive damage and possibly a fire.
CHECKING THE CARTRIDGE TYPE
FUSES
SV64005
1Good 2Melted
If the headlights or other electrical components do not
work and the blade type fuses are O.K., check the
cartridge type fuses. If any of the cartridge type fuses are
blown, they must be replaced.
If there is an overload in the circuits from the battery, the fuses
are designed to blow before the entire wiring harness is
damaged.
2003 IS300 from Aug. '02 Prod. (OM53439U)