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

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.
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329
CHECKING BRAKE FLUID
SV63001
To check the fluid level, simply look at the see±through
reservoir. The level should be between the ºMAXº and
ºMINº lines on the tank.
It is normal for the brake fluid level to go down slightly as the
brake pads wear or when the fluid level in the accumulator is
high.
If the reservoir needs frequent refilling, it may indicate a
serious mechanical problem.
If the level is low, add FMVSS No.116 DOT 3 or SAE J1703
brake fluid to the brake reservoir.
Refilling brake fluid:
1. Turn the ignition switch off.
2. Depress the brake pedal more than 40 times.
3. Remove the reservoir cap by hand. Add brake fluid up to
the ºMAXº line.If you do not follow the procedure above, the reservoir may
overflow.
Use only newly opened brake fluid. Once opened, brake fluid
absorbs
moisture from the air, and excess moisture can cause
a dangerous loss of braking efficiency.
CAUTION
Take care when filling the reservoir because brake fluid
can harm your hands or eyes and damage painted
surfaces. If fluid gets in your eyes, flush your eyes with
clean water immediately. If you still feel uncomfortable
with your eyes, go to the doctor.
NOTICE
If you spill some of the fluid, be sure to wipe it off to prevent it from damaging the parts or paintwork.
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330
CHECKING POWER STEERINGFLUID
SV63002
Check the fluid level on the dipstick. If necessary, add
automatic transmission fluid DEXRONII or III.
If the vehicle has been driven around 80 km/h (50 mph) for 20
minutes (a little more in frigid temperatures), the fluid is hot
(60 C ± 80C or 140F ± 175F). You may also check the level
when the fluid is cold (about room temperature, 10 C ± 30C
or 50F ± 85F) if the engine has not been run for about five
hours.
SV63003

1If cold O.K. 2If hot O.K. 3Add fluid
1. Clean all dirt off the reservoir.
2. Remove the reservoir cap by turning it counterclockwise
and wipe the dipstick clean.
3. Reinstall the reservoir cap.
4. Remove the reservoir cap again and look at the fluid level.
If the fluid is cold, the level should be in the ºCOLDº range on
the dipstick. Similarly, if it is hot, the fluid level should be in the
ºHOTº range. If the level is at the low side of either range, add
automatic transmission fluid DEXRON
II or III to bring the
level within the range.
5. After replacing the reservoir cap, visually check the
steering box case, vane pump and hose connections for leaks
or damage.
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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.
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332
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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333
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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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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335
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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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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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.
2003 IS300 from Aug. '02 Prod. (OM53439U)