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6-1. Specifications
6
Vehicle specifications
Fuel information
■Fuel tank opening for unleaded gasoline
To help prevent incorrect fueling, your Lexus has a fuel tank opening that only
accommodates the special nozzle on unleaded fuel pumps.
■If your engine knocks
●Consult your Lexus dealer.
●You may occasionally notice light knocking for a short time while accelerating
or driving uphill. This is normal and there is no need for concern.
Your vehicle must use only unleaded gasoline.
IS250
Premium unleaded gasoline with an oc tane rating of 91 (Research Octane
Number 96) or higher required for optimum engine performance. If 91
octane cannot be obtained, you may us e unleaded gasoline with an octane
rating as low as 87 (Research Octane Number 91). Use of unleaded gaso-
line with an octane rating lower than 91 may result in engine knocking. Per-
sistent knocking can lead to engine damage and should be corrected by
refueling with higher octane unleaded gasoline.
IS350
Premium unleaded gasoline with an oc tane rating of 91 (Research Octane
Number 96) or higher required for optimum engine performance. If 91
octane cannot be obtained, you may us e unleaded gasoline with an octane
rating as low as 87 (Research Octane Number 91). Use of unleaded gaso-
line with an octane rating lower than 91 may result in engine knocking and
significantly reduced perf ormance. Persistent knocking can lead to engine
damage and should be corrected by refueling with higher octane unleaded
gasoline.
At minimum, the gasoline you us e should meet the specifications of
ASTM D4814 in the U.S.A. an d CGSB3.5-M93 in Canada.
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6-1. Specifications
■Gasoline quality
In very few cases, driveability problems may be caused by the brand of gasoline you
are using. If driveability problems persist, try changing the brand of gasoline. If this
does not correct the problem, consult your Lexus dealer.
■Gasoline quality standards
●Automotive manufacturers in the US, Europe and Japan have developed a
specification for fuel quality called World-Wide Fuel Charter (WWFC) that is
expected to be applied worldwide.
●The WWFC consists of four categories that are based on required emission
levels. In the US, category 4 has been adopted.
●The WWFC improves air quality by lowering emissions in vehicle fleets, and
customer satisfaction th rough better performance.
■Lexus recommends the use of gasoline containing detergent additives
●Lexus recommends the use of gasoline that contains detergent additives to
avoid build-up of engine deposits.
●All gasoline sold in the US contains de tergent additives to clean and/or keep
clean intake systems.
■Lexus recommends the use of cleaner burning gasoline
Cleaner burning gasoline, including reform ulated gasoline that contains oxygen-
ates such as ethanol or MTBE (Methyl Tertiary Butyl Ether) is available in many
areas.
Lexus recommends the use of cleaner burning gasoline and appropriately blended
reformulated gasoline. These types of gasoline provide excellent vehicle perfor-
mance, reduce vehicle emissions and improve air quality.
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6
Vehicle specifications
■Lexus does not recommend blended gasoline
●If you use gasohol in your Lexus, be sure that it has an octane rating no lower
than 87.
●Lexus DOES NOT recommend the use of gasoline containing methanol.
■Lexus does not recommend gasoline containing MMT
Some gasoline contains oc tane enhancing additive called MMT (Methylcyclopen-
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.
●Use only gasoline containing a maxi-
mum of 10% ethanol.
DO NOT use any flex-fuel or gasoline
that could contain more than 10% etha-
nol, including from any pump labeled
E15, E30, E50, E85 (which are only
some examples of fuel containing more
than 10% ethanol).DO NOT use gasoline contain-
ing more than 10% ethanol.
(15% ethanol)
(50% ethanol)
(85% ethanol)
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6-1. Specifications
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.
●IS250: Use of unleaded gasoline with an octane rating lower than 91 may result
in engine knocking. Persistent knocking can lead to engine damage and should
be corrected by refueling with higher octane unleaded gasoline.
●IS350: Use of unleaded gasoline with an octane rating lower than 91 may result
in engine knocking and significantly re duced performance. Persistent knocking
can lead to engine damage and should be corrected by refueling with higher
octane unleaded gasoline.
■Fuel-related poor driveability
If after using a different type of fuel, poor driveability is encountered (poor hot start-
ing, vaporization, engine knoc king, 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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6-1. Specifications
6
Vehicle specifications
Tire information
Ty p i c a l t i r e s y m b o l s
Standard tire
Compact spare tire
Tire size (P. 543)
DOT and Tire Identification Number (TIN) ( P. 543)
Location of treadwear indicators ( P. 412)
Tire ply composition and materials
Plies are layers of rubber-coated parallel cords. Cords are the strands
which form the plies in a tire.
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6-1. Specifications
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. 4 1 9 )
Maximum cold tire inflation pressure ( P. 5 3 1 )
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 1 9 )
An all season tire has “M+S” on the sidewall. A tire not marked “M+S” is a
summer tire.
“TEMPORARY USE ONLY” ( P. 4 9 6 )
A compact spare tire is identified by the phrase “TEMPORARY USE
ONLY” molded into its sidewall. This tire is designed for temporary
emergency use only.
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6-1. Specifications
6
Vehicle specifications
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 that the tire conforms to applicable
Federal Motor Vehicle Safety
Standards.
Tire size
■ Typical tire size information
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)
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6-1. Specifications
■Tire dimensions
Section width
Ti r e h e i g h t
Wheel diameter
Tire section names
Bead
Sidewall
Shoulder
Tread
Belt
Inner liner
Reinforcing rubber
Carcass
Rim lines
Bead wires
Chafer
Uniform Tire Quality GradingThis information has b een prepared in accorda nce with regulations
issued by the National Highway Traf fic 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 an y questions you may have as you read
this information.