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4-3. Do-it-yourself maintenance
4
Maintenance and care
08_IS350/250_U_(L/O_0708)
Radiator and condenserCheck the radiator and condenser and clear any foreign objects.
If either of the above parts are extremely dirty or you are not sure of their
condition, have your vehicle checked by your Lexus dealer.
Brake fluid■ Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
Make sure to check the fluid type and prepare the necessary items.
■ Adding fluid
CAUTION
■When the engine is hot
Do not touch the radiator or condenser, as they may be hot and you may be burned.
Fluid typeFMVSS No.116 DOT 3 or SAE J1703 brake fluid
ItemsClean funnel
■Brake fluid can absorb moisture from the air
Excess moisture in the fluid can cause a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
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6-1. Specifications
6
Vehicle specifications
08_IS350/250_U_(L/O_0708)
Engine
Fuel
IS250IS350
Model4GR-FSE2GR-FSE
Ty p e6-cylinder V type,
4-cycle, gasoline6-cylinder V type,
4-cycle, gasoline
Bore and stroke3.27 × 3.03 in.
(83.0
× 77.0 mm)
3.70 × 3.27 in.
(94.0
× 83.0 mm)
Displacement 152.5 cu.in.
(2500 cm3)
210.9 cu.in.
(3456 cm3)
Drive belt tensionAutomatic adjustment
Fuel typeUnleaded gasoline only
Octane rating91 (Research octane number 96) or higher
Fuel tank capacity17.2 gal. (65 L, 14.3 lmp.gal)
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6
Vehicle specifications
08_IS350/250_U_(L/O_0708)
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 premium gasoline is not available
If 91 rating gasoline cannot be obtained, you may use unleaded gasoline with an
octane rating as low as 87 (Research Octane Rating 91).
■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.
■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.
Your vehicle must use only unleaded gasoline.
Premium unleaded gasoline with an octane rating of 91 (Research Octane
Number 96) or higher required for optimum engine performance.
At minimum, the gasoline you use should meet the specifications of
ASTM D4814 in the U.S.A. and CGSB3.5-M93 in Canada.
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6-1. Specifications
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■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 through 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 detergent additives to clean and/or keep
clean intake systems.
■Lexus recommends the use of cleaner burning gasoline
Cleaner burning gasoline, including reformulated 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.
■Lexus does not recommend blended gasoline
●Lexus allows the use of oxygenate blended gasoline where the oxygenate con-
tent is up to 10% ethanol or 15% MTBE.
●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 octane 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 instrument cluster may come on. If this hap-
pens, contact your Lexus dealer for service.
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6
Vehicle specifications
08_IS350/250_U_(L/O_0708)
NOTICE
■Notice on gasoline quality
●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 reduced 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 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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6-1. Specifications
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Vehicle specifications
08_IS350/250_U_(L/O_0708)■
Tire dimensions
Section width
Tire height
Wheel diameter
Tire section names
Bead
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.A. 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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Tire related termMeaning
Bead
The part of the tire that is made of steel wires,
wrapped or reinforced by ply cords and that is
shaped to fit the rim
Bead separationA breakdown of the bond between components in
the bead
Bias ply tire
A pneumatic tire in which the ply cords that extend to
the beads are laid at alternate angles substantially
less than 90 degrees to the centerline of the tread
CarcassThe tire structure, except tread and sidewall rubber
which, when inflated, bears the load
ChunkingThe breaking away of pieces of the tread or sidewall
CordThe strands forming the plies in the tire
Cord separationThe parting of cords from adjacent rubber com-
pounds
CrackingAny parting within the tread, sidewall, or innerliner of
the tire extending to cord material
CT
A pneumatic tire with an inverted flange tire and rim
system in which the rim is designed with rim flanges
pointed radially inward and the tire is designed to fit
on the underside of the rim in a manner that encloses
the rim flanges inside the air cavity of the tire
Extra load tire
A tire designed to operate at higher loads and at
higher inflation pressures than the corresponding
standard tire
GrooveThe space between two adjacent tread ribs
InnerlinerThe layer(s) forming the inside surface of a tubeless
tire that contains the inflating medium within the tire
Innerliner separationThe parting of the innerliner from cord material in the
carcass
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Vehicle specifications
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Tire related termMeaning
Intended outboard side-
wall
(a) The sidewall that contains a whitewall, bears white lettering, or bears manufacturer, brand,
and/or model name molding that is higher or
deeper than the same molding on the other side-
wall of the tire, or
(b) The outward facing sidewall of an asymmetrical tire that has a particular side that must always
face outward when mounted on a vehicle
Light truck (LT) tire
A tire designated by its manufacturer as primarily
intended for use on lightweight trucks or multipur-
pose passenger vehicles
Load ratingThe maximum load that a tire is rated to carry for a
given inflation pressure
Maximum load ratingThe load rating for a tire at the maximum permissible
inflation pressure for that tire
Maximum permissible
inflation pressureThe maximum cold inflation pressure to which a tire
may be inflated
Measuring rimThe rim on which a tire is fitted for physical dimension
requirements
Open spliceAny parting at any junction of tread, sidewall, or
innerliner that extends to cord material
Outer diameterThe overall diameter of an inflated new tire
Overall width
The linear distance between the exteriors of the side-
walls of an inflated tire, including elevations due to
labeling, decorations, or protective bands or ribs
Passenger car tire
A tire intended for use on passenger cars, multipur-
pose passenger vehicles, and trucks, that have a
gross vehicle weight rating (GVWR) of 10000 lb. or
less.
PlyA layer of rubber-coated parallel cords