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April 27, 2009 10:09 am
■Lexus does not recommend gasoline containing MMT
Some gasoline contains octane enhancing additive called MMT (Methylcy clopen-
tadienyl Manganese Tricarbonyl).
Lexus DOES NOT recommend the use of gasoline that contains MMT. If fuel con-
taining MMT is used, your emission control system may be adversely affected.
The malfunction indicator lamp on the inst rument cluster may come on. If this hap-
pens, contact your Lexus dealer for service.
NOTICE
■Notice on fuel quality
●Do not use improper fuels. If improper fuels are used the engine will be damaged.
●Do not use leaded gasoline.
Leaded gasoline can cause damage to your vehicle’s three-way catalytic convert-
ers causing the emission control system to malfunction.
●Do not use gasohol other than that stated here.
Other gasohol may cause fuel system damage or vehicle performance problems.
●Using unleaded gasoline with an octane number or rating lower than that stated
here will cause persistent heavy knocking.
At worst, this will lead to engine damage.
■Fuel-related poor driveability
If after using a different type of fuel, poor driveability is encountered (poor hot start-
ing, vaporization, engine knocking, etc.), discontinue the use of that type of fuel.
■When refueling with gasohol
Take care not to spill gasohol. It can damage your vehicle’s paint.
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Vehicle specifications
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Tire information
Ty p i c a l t i r e s y m b o l s
Tire size(→ P. 580)
DOT and Tire Identification Number (TIN) (→P. 5 7 9 )
Location of treadwear indicators (→ P. 4 5 2 )
Run-flat tire (RFT) or standard tire (→ P. 546)
This vehicle can be equipped with either run-flat tires (RFT) or standard
tires. A “RFT” or “DSST” mark is molded on the sidewall of the run-flat tire.
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GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
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 filled in the tire. A
tube type tire has a tube inside the ti re and the tube maintains the air pres-
sure.
Load limit at maximum cold tire inflation pressure ( →P. 583)
Maximum cold tire inflation pressure ( →P. 583)
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 tire or all season tire (→ P. 4 5 7 )
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 into its sidewall. This tire is designed for temporary emer-
gency use only.
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Vehicle specifications
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Typical DOT and tire identification number (TIN)DOT symbol
*
Tire Identification Number (TIN)
Tire manufacturer’s identifica-
tion mark
Tire size code
Manufacturer’s optional tire
type code (3 or 4 letters)
Manufacturing week
Manufacturing year
*: The DOT symbol certifies thatthe tire conforms to applicable
Federal Motor Vehicle Safety
Standards.
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GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Tire size
■ Typical tire size information
Ty p e A
The illustration indicates typical
tire size.
Ti r e u s e
(P = Passenger car,
T = Temporary use)
Section width (millimeters)
Aspect ratio
(tire height to section width)
Tire construction code
(R = Radial, D = Diagonal)
Wheel diameter (inches)
Load index (2 or 3 digits)
Speed symbol
(alphabet with one letter)
Speed category
(alphabet with one letter)
■ Tire dimensions
Section width
Ti r e h e i g h t
Wheel diameter
Ty p e B
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Vehicle specifications
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Tire section namesBead
Sidewall
Shoulder
Tr e a d
Belt
Inner liner
Reinforcing rubber
Carcass
Rim lines
Bead wires
Chafer
Uniform Tire Quality GradingThis information has been prepared in accordance with regulations
issued by the National Highway Traffic Safety Administration of the U.S.
Department 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.
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GS_HV_U (OM30B44U)
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■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 gov-
ernment 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 varia-
tions in driving habits, service practices and differences in road characteris-
tics 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.
Warning: The traction grade assigned to this tire is based on braking
(straight ahead) traction tests and does not include cornering (turning) trac-
tion.
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Vehicle specifications
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
■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 fail-
ure.
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.
Glossary of tire terminology
Tire related termMeaning
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Maximum inflation pres-
sureThe maximum cold inflated pressure to which a tire
may be inflated, shown on the sidewall of the tire
Recommended inflation
pressureCold tire inflation pressure recommended by a man-
ufacturer
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