tire size Lexus IS250 2015 TIPS FOR THE NAVIGATION SYSTEM / LEXUS 2015 IS250/350 (OM53C50U) User Guide

4307-3. Do-it-yourself maintenance
IS350/250_U (OM53C50U)
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drivetrain as well as dangerous han-
dling characteristics, which may lead to an accident resulting in death or serious 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.
●Do not tow if your vehicle has a compact spare tire installed.
■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 pressu re is low, or it may come on when the tire
inflation pressure is actually normal.
■Caution regarding interference with electronic devices
●Users of any electrical medical device other than implantable cardiac pacemakers,
cardiac resynchronization therapy-pacemakers or implantable cardioverter defibril-
lators should consult the ma nufacturer of the device for information about its opera-
tion under the influence of radio waves.
Radio waves could have unexpected effe cts on the operation of such medical
devices.
●People with implantable cardiac pacemakers,
cardiac resynchronization therapy-pacemak-
ers or implantable cardioverter defibrillators
should not come within 17.7 in. (450 mm) of
the tire pressure warning system initiators.
The radio waves may affect the operation of
such devices.

4327-3. Do-it-yourself maintenance
IS350/250_U (OM53C50U)
The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
( P. 5 1 9 )
Tire inflation pressure
Tire inflation pressure

4357-3. Do-it-yourself maintenance
7
Maintenance and care
IS350/250_U (OM53C50U)
When replacing wheels, care should be taken to ensure that they are equivalent
to those removed in load capacity, diameter, rim width and inset
*.
Replacement wheels are available at your Lexus dealer.
*: Conventionally referred to as “offset”.
Lexus does not recommend using the following:
●Wheels of different sizes or types
●Used wheels
●Bent wheels that have been straightened
●Use only Lexus wheel nuts and wrenches designed for use with your alumi-
num wheels.
●When rotating, repairing or changing your tires, check that the wheel nuts are
still tight after driving 1000 miles (1600 km).
●Be careful not to damage the aluminum wheels when using tire chains.
●Use only Lexus genuine balance weights or equivalent and a plastic or rubber
hammer when balancing your wheels.
■When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning valves and transmit-
ters that allow the tire pressure warning system to provide advance warning in the event
of a loss in tire inflation pressure. Whenever wheels are replaced, tire pressure warning
valves and transmitters must be installed. ( P. 4 2 4 )
Wheels
If a wheel is bent, cracked or heavily corroded, it should be replaced. Other-
wise, the tire may separate from the wheel or cause a loss of handling control.
Wheel selection
Aluminum wheel precautions

4367-3. Do-it-yourself maintenance
IS350/250_U (OM53C50U)
CAUTION
■When replacing wheels
●Do not use wheels that are a different size from those recommended in the Owner’s
Manual, as this may result in a loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a tubeless tire. Doing
so may result in an accident, causing death or serious injury.
NOTICE
■Replacing tire pressure warning valves and transmitters
●Because tire repair or replacement may affect the tire pressure warning valves and
transmitters, make sure to have tires servic ed by your Lexus dealer or other qualified
service shop. In addition, make sure to pu rchase your tire pressure warning valves
and transmitters at your Lexus dealer.
●Ensure that only genuine Lexus wheels are used on your vehicle.
Tire pressure warning valves and transmitte rs may not work properly with non-genu-
ine wheels.

4718-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
CAUTION
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold and
inflated to the inflation pressure recomm ended by the vehicle manufacturer on the
vehicle placard or tire inflation pressure la bel (tire and load information label). (If your
vehicle has tires of a different size than the size indicated on the vehicle placard or tire
inflation pressure label [tire and load in formation label], you should determine the
proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire pressure moni-
toring system (TPMS-tire pressure warning system) that illuminates a low tire pressure
telltale (tire pressure warning light) when on e or more of your tires is significantly
under-inflated. Accordingly, when the low ti re pressure telltale (tire pressure warning
light) illuminates, you should stop and check your tires as soon as possible, and inflate
them to the proper pressure. Driving on a significantly under-inflated tire causes the
tire to overheat and can lead to tire failure. Under-inflation also reduces fuel efficiency
and tire tread life, and ma y affect the vehicle’s handling and stopping ability.
Please note that the TPMS (tire pressure wa rning system) is not a substitute for proper
tire maintenance, and it is the driver’s resp onsibility to maintain correct tire pressure,
even if under-inflation has no t reached the level to trigger illumination of the TPMS low
tire pressure telltale (tire pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warning system) mal-
function indicator to indicate when the system is not operating properly. The TPMS
(tire pressure warning system) malfunction indi cator is combined with the low tire pres-
sure telltale (tire pressure warning light). When the system detects a malfunction, the
telltale will flash for approximately one minu te and then remain continuously illumi-
nated. This sequence will cont inue upon subsequent vehicle start-ups as long as the
malfunction exists. When the malfunction indicator is illuminated, the system may not
be able to detect or signal low tire pressure as intended.
TPMS (tire pressure warning system) malfun ctions may occur for a variety of reasons,
including the installation of replacement or alternate tires or wheels on the vehicle that
prevent the TPMS (tire pressure warning system) from functioning properly. Always
check the TPMS (tire pressure warning syst em) malfunction telltale after replacing one
or more tires or wheels on your vehicle to ensure that the replacement or alternate
tires and wheels allow the TPMS (tire pressure warning system) to continue to function
properly.
NOTICE
■To ensure the tire pressure warning system operates properly
Do not install tires with different specificatio ns or makers, as the tire pressure warning
system may not operate properly.

4948-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
■The compact spare tire
●The compact spare tire is identified by the label “TEMPORARY USE ONLY” on the
tire sidewall.
Use the compact spare tire temporarily, and only in an emergency.
●Make sure to check the tire inflation pressure of the compact spare tire.
(  P. 5 1 9 )
■When using the compact spare tire
As the compact spare tire is not equipped wi th a tire pressure warning valve and trans-
mitter, low inflation pressure of the spare ti re will not be indicated by the tire pressure
warning system. Also, if you replace the compact spare tire after the tire pressure warn-
ing light comes on, th e light remains on.
■When the compact spare tire is equipped
The vehicle becomes lower when driving with the compact spare tire compared to when
driving with standard tires.
■If you have a flat rear tire on a road covered with snow or ice (vehicles with front and
rear tires of the same size)
Install the compact spare tire on one of the front wheels of the vehicle. Perform the fol-
lowing steps and fit tire chains to the rear tires:
Replace a front tire with the compact spare tire.
Replace the flat rear tire with the tire removed from the front of the vehicle.
Fit tire chains to the rear tires.
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5199-1. Specifications
9
Vehicle specifications
IS350/250_U (OM53C50U)
Ty p e A
Ty p e B
Ty p e C
Tires and wheels
Ti r e s i z e205/55R16 91W, T125/70D17 98M (spare)
Tire inflation pressure
(Recommended cold tire
inflation pressure)
Front tire 36 psi (250 kPa, 2.5 kgf/cm2 or bar)
Rear tire 36 psi (250 kPa, 2.5 kgf/cm
2 or bar)
Spare tire 60 psi (420 kPa, 4.2 kgf/cm
2 or bar)
Wheel size16  7J, 17  4T (spare)
Wheel nut torque76 f t•lbf (103 N•m, 10.5 kgf•m)
Ti r e s i z e225/45R17 91W, T125/70D17 98M (spare)
Tire inflation pressure
(Recommended cold tire
inflation pressure)
Front tire
36 psi (250 kPa, 2.5 kgf/cm2 or bar)
Rear tire 36 psi (250 kPa, 2.5 kgf/cm
2 or bar)
Spare tire 60 psi (420 kPa, 4.2 kgf/cm
2 or bar)
Wheel size17  7 1 /2J, 17  4T (spare)
Wheel nut torque76 f t•lbf (103 N•m, 10.5 kgf•m)
Ti r e s i z e225/45R17 91V, T125/70D17 98M (spare)
Tire inflation pressure
(Recommended cold tire
inflation pressure)
Front tire
36 psi (250 kPa, 2.5 kgf/cm2 or bar)
Rear tire 36 psi (250 kPa, 2.5 kgf/cm
2 or bar)
Spare tire 60 psi (420 kPa, 4.2 kgf/cm
2 or bar)
Wheel size17  7 1 /2J, 17  4T (spare)
Wheel nut torque76 f t•lbf (103 N•m, 10.5 kgf•m)

5209-1. Specifications
IS350/250_U (OM53C50U)
Ty p e D
Ty p e E
Ti r e s i z e225/40R18 88Y, 255/35R18 90Y,
T125/70D17 98M (spare)
Tire inflation pressure
(Recommended cold tire
inflation pressure)
Front tire 36 psi (250 kPa, 2.5 kgf/cm2 or bar)
Rear tire
36 psi (250 kPa, 2.5 kgf/cm
2 or bar)
Spare tire 60 psi (420 kPa, 4.2 kgf/cm
2 or bar)
Wheel size18  8J (225/40R18), 18  8 1 /2J (255/35R18),
17  4T (spare)
Wheel nut torque76 f t•lbf (103 N•m, 10.5 kgf•m)
Ti r e s i z e225/40R18 88W, 255/35R18 90W,
T125/70D17 98M (spare)
Tire inflation pressure
(Recommended cold tire
inflation pressure)
Front tire
36 psi (250 kPa, 2.5 kgf/cm2 or bar)
Rear tire 36 psi (250 kPa, 2.5 kgf/cm
2 or bar)
Spare tire 60 psi (420 kPa, 4.2 kgf/cm
2 or bar)
Wheel size18  8J (225/40R18), 18  8 1 /2J (255/35R18),
17  4T (spare)
Wheel nut torque76 f t•lbf (103 N•m, 10.5 kgf•m)

5259-1. Specifications
9
Vehicle specifications
IS350/250_U (OM53C50U)
Full-size tire
Compact spare tire
Tire information
Ty p i c a l t i r e s y m b o l s

5289-1. Specifications
IS350/250_U (OM53C50U)
■Typical tire size information
The illustration indicates typical tire
size. Tire use (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 digits or 3 digits)
Speed symbol
(alphabet with one letter)
■Tire dimensions
Section width
Tire height
Wheel diameter
Tire size
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