tire size Lexus IS300 2005 Basic Functions / LEXUS 2005 IS300 (OM53489U) User Guide

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1Tire size: For details, see ªTire sizeº on page
358.
2DOT and Tire Identification Number (TIN): For
details, see ªDOT and Tire Identification Number
(TIN)º on page 358.
3Maximum cold tire inflation pressure: This
means the pressure to which a tire may be
inflated. For recommended cold tire inflation
pressure, see ªSpecificationsº on page 344, 346
or 347.
4Load limit at maximum cold tire inflation
pressure: For details, see ªChecking and
replacing tiresº on page 368.
5Turning indicator: Some vehicles are equipped
with directional tires. For details, see ªRotating
tiresº on page 366 or 367.
6Tire ply composition and materials : Plies
mean a layer of rubber±coated parallel cords.
Cords mean the strands forming the plies in the
tire.
7Uniform tire quality grading: For details, see
ªUniform tire quality gradingº that follows.
8Location of tread wear indicators: For details,
see ªChecking and replacing tiresº on page 368.
9ªTUBELESSº or ªTUBE TYPEº: A tubeless tire
does not have a tube inside the tire and air is
directly filled in the tire. A tube type tire has a tube
inside the tire and the tube maintains the air
pressure.
10Radial tires or bias±ply tires: A radial tire has
ªRADIALº on the sidewall. A tire not marked with
ªRADIALº is a bias±ply tire.
11Summer tire or all season tire: An all season
tire has ªM+Sº on the sidewall. The tire not
marked with ªM+Sº is a summer tire. For details,
see ªTypes of tiresº on page 365.
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1ªTEMPORARY USE ONLYº: A compact spare
tire is identified by the phrase ªTEMPORARY
USE ONLYº molded into its sidewall. This tire is
designed for temporary emergency use only. For
details, see ªCompact spare tireº on page 287.
2Tire size: For details, see ªTire sizeº on page
358.
3DOT and Tire Identification Number (TIN): For
details, see ªDOT and Tire Identification Number
(TIN)º on page 358.
4Location of tread wear indicators: For details,
see ªChecking and replacing tiresº on page 368.
5Load limit at maximum cold tire inflation
pressure: For details, see ªChecking and
replacing tiresº on page 368.
6Maximum cold tire inflation pressure: This
means the pressure to which a tire may be
inflated. For recommended cold tire inflation
pressure, see ªSpecificationsº on page 344, 346
or 347.
7Tire ply composition and materials : Plies
mean a layer of rubber±coated parallel cords.
Cords mean the strands forming the plies in the
tire.
8ªTUBELESSº or ªTUBE TYPEº: A tubeless tire
does not have a tube inside the tire and air is
directly filled in the tire. A tube type tire has a tube
inside the tire and the tube maintains the air
pressure.
9Radial tires or bias±ply tires: A radial tire has
ªRADIALº on the sidewall. A tire not marked with
ªRADIALº is a bias±ply tire.
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DOT and Tire Identification Number (TIN)
SV63015

The illustration indicates typical DOT and TireIdentification Number (TIN)
1ªDOTº symbol
2Tire Identification Number (TIN)
3Tire manufacturer's identification mark
4Tire size code
5Manufacturer's optional tire type code
6Manufacturing week
7Manufacturing year
The ªDOTº symbol certifies that the tire conforms to
applicable Federal Motor Vehicle Safety Standards.
Tire size
SV63014b

Type A
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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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Tire related termMeaning
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
Vehicle maximum load on
the tirethe load on an individual tire that is determined by distributing to eac\
h axle its
share of the maximum loaded vehicle weight and dividing by two
Vehicle normal load on
the tirethe load on an individual tire that is determined by distributing to eac\
h axle its
share of the curb weight, accessory weight, and normal occupant weight
(distributed in accordance with Table 1 that follows) and dividing by two
Weather sidethe surface area of the rim not covered by the inflated tire
Table 1 ± Occupant loading and distribution for vehicle normal load fo\
r various designated seating capacitiesDesignated seating capacity,Number of occupants
Vehicle normal load,
Number of occupantsOccupant distribution in a normally loaded vehicle
2 through 422 in front
5 through 1032 in front, 1 in second seat
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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 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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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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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.
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.
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.
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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.
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 ªSº 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 local
regulations before installing chains.
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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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