Speed Lexus IS300 2005 Basic Functions / LEXUS 2005 IS300 (OM53489U) Repair Manual

CHASSIS
344
± TIRES AND WHEELS (Type A)
Standard tire:Tire sizeFront
Rear
215/45ZR17
225/45ZR17
Tire inflation pressureRecommended cold tire inflation pressure
Front 230 kPa (2.3 kgf/cm2 or bar, 33 psi)
Rear 240 kPa (2.4 kgf/cm2 or bar, 35 psi)
For sustained high speeds above 160 km/h (100 mph), in
countries where such speeds are permitted by law, add 70 kPa
(0.8 kgf/cm
2, 0.7 bar, 10 psi) to the front tires and rear tires, but
never exceed the maximum cold tire pressure molded on the tire
sidewall.
Wheel size
Front
Rear
17 x 7 JJ
17 x 7 1/2 JJ
Wheel nut torque103 N´m (10.5 kgf´m, 76 ft´lbf.)
Spare tire:
Tire size
215/45ZR17
Tire inflation pressureRecommended cold tire inflation pressure
240 kPa (2.4 kgf/cm2 or bar, 35 psi)
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CHASSIS
346
± TIRES AND WHEELS (Type B)Tire size
215/45ZR17
Tire inflation pressure
Recommended cold tire inflation pressure
Front 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 70 kPa
(0.8 kgf/cm
2, 0.7 bar, 10 psi) to the front tires and rear tires, but
never exceed the maximum cold tire pressure molded on the tire
sidewall.
Wheel size17 x 7 JJ
Wheel nut torque103 N´m (10.5 kgf´m, 76 ft´lbf.)
NOTE:
For complete information on tires (e.g. replacing tires or replacing wh\
eels), see ªChecking tire inflation pressureº
through ªAluminum wheel precautionsº on page 351 through 374.
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CHASSIS
347
± TIRES AND WHEELS (Type C)
Standard tire:Tire size
P205/55R16 89V
Tire inflation pressureRecommended cold tire inflation pressure
Front 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/cm
2, 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 size
T125/70D17 98M
Tire inflation pressure420 kPa (4.2 kgf/cm2 or bar, 60 psi)
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359
SV63013a

Type BThe illustration indicates typical tire size.
1Tire use (P=Passenger car, T=Temporary use)
2Section width (in millimeters)
3Aspect ratio (tire height to section width)
4Speed category (alphabet with one letter)
5Tire construction code(R=Radial, D=Diagonal)
6Wheel diameter (in inches)
7Load index (2 digits or 3 digits)
8Speed symbol (alphabet with one letter)
SV63012c

1Section width
2Tire height
3Wheel diameter
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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.
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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.
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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.
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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.
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NOTICE
If the wrong combination of tire and chain is used, thechains 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 curves to avoid
losing control of the vehicle, it may cause an
accident.
NOTICE
Do not attempt to use a tire chain on the compact spare tire, as it may result in damage to the vehicle as well asthe tire.
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373
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 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.
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