2012 Lexus IS250 wheel size

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1-3. Adjustable components (seats, mirrors, steering wheel)
■People suffering illness
Obtain medical advice and wear the seat belt in the proper way.
■Child seat belt usage
The seat belts of your vehicle are principally designed for persons of adult size.
●Use a child restraint system appropriate for the child, until the child becomes
large enough to properly wear the vehicle's seat belt. ( P. 114)
●When the child becomes large enough to properly wear the vehicle's seat belt,
follow the instructions on P. 65 regarding seat belt usage.
■Replacing the belt after the pretensioner has been activated
If the vehicle is involved in multiple collisions, the pretensioner will activate for the
first collision, but will not activate for the second or subsequent collisions.
■Seat belt extender
If your seat belts cann ot be fastened securely
because they are not long enough, a person-
alized seat belt extender is available from
your Lexus dealer free of charge.

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2-4. Using other driving systems
2
When driving
CAUTION
■TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the TRAC system is operating.
Do not drive the vehicle in conditions where stability and power may be lost.
■If hill-start assist control does not operate effectively
(vehicles with an automatic transmission)
Do not overly rely on the hill-start assist co ntrol. The hill-start assist control may not
operate effectively on steep incl ines and roads covered in ice.
■When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may cause
an accident, resulting in death or serious injury. Exercise particular care when the
indicator light flashes.
■When TRAC and VSC are off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are systems to help enhance vehicle stability and driving force, do not turn off
TRAC and VSC unless necessary.
■Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
pressure level.
The ABS, VSC and TRAC systems will not func tion correctly if different tires are fit-
ted on the vehicle.
Contact your Lexus dealer for further info rmation when replacing tires or wheels.
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will affect the driv-
ing assist systems, and may cause the system to malfunction.

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2-5. Driving information
Winter driving tips
Carry out the necessary preparations and inspections before driving the
vehicle in winter. Always drive the vehicle in a manner appropriate to the
prevailing weather conditions.
■ Pre-winter preparations
●Use fluids that are appropria te to the prevailing outside tempera-
tures.
• Engine oil
• Engine coolant
• Washer fluid
● Have a service technician inspect the level and specific gravity of
battery electrolyte.
● Have the vehicle fitted with four snow tires or purchase a set of
tire chains for the rear tires.
Ensure that all tires are the specified size and the same brand, and that
chains match the size of the tires.
■ Before driving the vehicle
Perform the following according to the driving conditions.
● Do not try to forcibly open a w indow or move a wiper that is fro-
zen. Pour warm water over the frozen area to melt the ice. Wipe
away the water immediately to prevent it from freezing.
● To ensure proper operation of the climate control system fan,
remove any snow that has accumu lated on the air inlet vents in
front of the windshield.
● Remove any ice that has accumul ated on the vehicle chassis.
● Periodically check for and remove any excess ice or snow that
may have accumulated in the wheel well or on the brakes.

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2-5. Driving information
2
When driving
Selecting tire chainsTire chains can be mounted on 16- and 17-inch tires. They cannot be
mounted on 18-inch tires. Use the co rrect tire chain size when mounting
the tire chains. Chain size is regulated for each tire size.
Side chain
(0.12 in. [3 mm] in diameter)
Cross chain
(0.16 in. [4 mm] in diameter)
Regulations on the use of tire chains
● Regulations regarding the use of tire chains vary according to location
and type of road. Always check local regulations before installing
chains.
● Install the chains on the rear tires.
● Retighten the chains after driving 1 /4  1 /2 mile (0.5  1.0 km).
■When driving the vehicle
Accelerate the vehicle slowly and dr ive at a reduced speed suitable
to road conditions.
■ When parking the vehicle
Park the vehicle and move the shift lever to P (automatic transmis-
sion) or 1 or R (manual transmis sion) without setting the parking
brake. The parking brake may freez e up, preventing it from being
released. If necessary, block the wheels to prevent inadvertent slid-
ing or creeping.

208
2-5. Driving information
■Snow chain installation
Observe the following precautions when installing and removing chains.
●Install and remove tire chains in a safe location.
●Install tire chains on the rear tires only. Do not install tire chains on front tires.
●Install the tire chains on rear tires as tightly as possible. Retighten chains after
driving 1 /4 - 1 /2 mile (0.5 - 1.0 km).
●Install tire chains following the instructions provided in the accompanying
instructions.
CAUTION
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in a loss of vehicle control and cause death or serious
injury.
●Use tires of the size specified for your vehicle.
●Maintain the recommended level of air pressure.
●Do not drive in excess of 75 mph (120 km/h ), regardless of the type of snow tires
being used.
●Use snow tires on all, not just some wheels.
■Driving with tire chains
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in the vehicle being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed limit specified for the tire chains being used,
or 30 mph (50 km/h), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden turns and braking, as use of chains may adversely affect vehicle
handling.
●Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.

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4-3. Do-it-yourself maintenance
Installing tire pressure warning valves and transmittersWhen replacing tires or wheels, tire pressure warning valves and trans-
mitters must also be installed.
When new tire pressure warning va lves and transmitters are installed,
new tire pressure warning valve and transmitter ID codes must be regis-
tered in the tire pressure warning computer and tire pressure warning
system must be initialized. Have tire pressure warning valve and transmit-
ter ID codes registered by your Lexus dealer. ( P. 4 1 6 )
Initializing the tire pressure warning system
■ The tire pressure warning system must be initialized in the following
circumstances:
●When rotating the tires on vehicles differing with front and rear tire
inflation pressures.
● When changing the ti re inflation pressure by changing traveling
speed.
● When changing the tire size.
When the tire pressure warning sy stem is initialized, the current tire
inflation pressure is set as the pressure benchmark.

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4-3. Do-it-yourself maintenance
■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits, cracks deep enough to expose the
fabric or bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or
location of a cut or other damage
If you are not sure, consult with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered,
the tire pressure warning system will not work properly. After driving for about 20
minutes, the tire pressure warning light blin ks for 1 minute and stays on to indicate a
system malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if it has sel-
dom or never been used or damage is not obvious.
■If the tread wears down below 0.16 in. (4 mm) on snow tires
The effectiveness of snow tires is lost.
■Low profile tires (models not equipped with 16-inch tires)
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when co mpared to standard tires. Be sure to
use snow tires or tire chains
* on snowy and/or icy roads and drive carefully at a
speed appropriate for road and weather conditions.
*: Tire chains cannot be mounted on 18-inch tires.

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4-3. Do-it-yourself maintenance
4
Maintenance and care
■Maximum load of tire
Check that the maximum load of the replacement tire is greater than 1 /2 of the
Gross Axle Weight Ratings (GAWR) of either the front axle or the rear axle, which-
ever is greater.
■Tire types
1 Summer tires
Summer tires are high-speed performance tires best suited to highway driving
under dry conditions. Since summer tires do not have the same traction perfor-
mance as snow tires, summer tires are inadequate for driving on snow-covered
or icy roads. For driving on snow-covered roads or icy roads, the use of snow tires
is recommended. When installing snow tires, be sure to replace all four tires.
2 All season tires All season tires are designed to provide better traction in snow and to be ade-
quate for driving in most winter conditions , as well as for use year round. All sea-
son tires, however, do not have adequate traction performance compared with
snow tires in heavy or loose snow. Also, al l season tires fall short in acceleration
and handling performance compared with summer tires in highway driving.
3Snow tires
For driving on snow-covered roads or ic y roads, we recommend using snow tires.
If you need snow tires, select tires of the same size, construction and load capac-
ity as the originally installed tires. Since your vehicle has radial tires as original
equipment, make sure your snow tires also have radial construction. Do not install
studded tires without first checking loca l regulations for possible restriction.
Snow tires should be installed on all wheels. ( P. 2 0 6 )
■Initializing the tire pressure warning system
Initialize the tires with the tire inflatio n pressure adjusted to the specified level.
For the GAWR, see the Certification Label.
For the maximum load of the tire, see the load
limit at maximum cold tire inflation pressure
mentioned on the sidewall of the tire.
(
P. 5 4 1 ) .