2013 Lexus GS450h treadwear

651
GS450h_U (OM30D01U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Tires
New tread
Treadwear indicator
Worn tread
The location of treadwear indicators is
shown by the “TWI” or “ ∆” marks, etc.,
molded on the sidewall of each tire.
Check spare tire condition and pres-
sure if not rotated.
Replace or rotate tires in accord ance with maintenance schedules and
treadwear.
Checking tires
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2
3
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GS450h_U (OM30D01U)
6596-3. Do-it-yourself maintenance
6
Maintenance and care
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as dangerous
handling characteristics, which may lead to an accident resulting in death or seri-
ous injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
■When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first adjusting the tire
inflation pressure to the specified level. Otherwise, the tire pressure warning light
may not come on even if the tire inflation pressure is low, or it may come on when
the tire inflation pressure is actually normal.
■Caution regarding interference with electronic devices (vehicles with the tire
inflation pressure display function)
●Users of any electrical medical device other than implanted pacemakers and
implanted cardiac defibrillators should consult the manufacturer of the device for
information about its operation under the influence of radio waves.
Radio waves could have unexpected effects on the operation of such medical
devices.
●People with implanted pacemakers or car-
diac defibrillators should not come within
17.7 in. (450 mm) of the tire pressure warn-
ing system initiators. The radio waves may
affect the operation of such devices.
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GS450h_U (OM30D01U)
8-1. Specifications
Tire size (→ P. 7 9 8 )
DOT and Tire Identification Number (TIN) (→P. 7 9 7 )
Location of treadwear indicators (→ P. 6 5 1 )
Tire ply composition and materials
Plies are layers of rubber-coated parallel cords. Cords are the strands which form
the plies in a tire.
Radial tires or bias-ply tires
A radial tire has “RADIAL” on the sidewall. A tire not marked “RADIAL” is a bias-
ply tire.
TUBELESS or TUBE TYPE
A tubeless tire does not have a tube and air is directly put into the tire. A tube type
tire has a tube inside the tire and the tube maintains the air pressure.
Load limit at maximum cold tire inflation pressure ( →P. 8 0 2 )
Maximum cold tire inflation pressure ( →P. 8 0 2 )
This means the pressure to which a tire may be inflated.
Uniform tire quality grading
For details, see “Uniform Tire Quality Grading” that follows.
Summer tires or all season tires (→P. 6 5 6 )
An all season tire has “M+S” on the sidewall. A tire not marked “M+S” is a summer
tire.
“TEMPORARY USE ONLY”
A compact spare tire is identified by the phrase “TEMPORARY USE ONLY”
molded on its sidewall. This tire is designed for temporary emergency use only.
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2
3
4
5
6
7
8
9
10
11
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GS450h_U (OM30D01U)
8-1. Specifications
This information has been prepared in accordance with regulations issued
by the National Highway Traffic Safety Administration of the U.S. Depart-
ment of Transportation.
It provides the purchasers and/or prospective purchasers of Lexus vehi-
cles 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 Require-
ments 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 govern-
ment 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. Performance may differ significantly from the norm due to variations in
driving habits, service practices and differences in road characteristics and cli-
mate.
■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.
Uniform Tire Quality Grading
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GS450h_U (OM30D01U)
8-1. Specifications
*:Table 1  Occupant loading and distribution for vehicle normal load for various
designated seating capacities
Te s t r i mThe rim on which a tire is fitted for testing, and may be
any rim listed as appropriate for use with that tire
TreadThat portion of a tire that comes into contact with the
road
Tread ribA tread section running circumferentially around a
tire
Tread separationPulling away of the tread from the tire carcass
Treadwear indicators
(TWI)The projections within the principal grooves
designed to give a visual indication of the degrees of
wear of the tread
Wheel-holding fixtureThe fixture used to hold the wheel and tire assembly
securely during testing
Tire related termMeaning
Designated seating
capacity, Number of occupantsVehicle 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
11 through 155
2 in front, 1 in second seat, 1 in third seat, 1 in fourth seat
16 through 207
2 in front, 2 in second seat, 2 in third seat, 1 in fourth seat
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