wheel size LEXUS RX450h 2015 Owners Manual

1011-4. Adjustable components (seats, mirrors, steering wheel)
1
Before driving ■
Emergency locking retractor (ELR)
The retractor will lock the belt during a sudd en stop or on impact. It may also lock if
you lean forward too quickly. To allow the belt to extend, retract the belt and then
pull it slowly.■
Automatic locking retractor (ALR)
When a passenger's shoulder belt is completely extended and then retracted even
slightly, the belt is locked in that position and cannot be extended. This feature is
used to hold the child restraint system (CRS) firmly. To free the belt again, fully
retract the belt and then pull the belt out once more. (  P. 1 5 4 )■
Child seat belt usage
The seat belts of your vehicle were princi pally 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. 1 5 0 )●
When the child becomes large enough to properly wear the vehicle's seat belt,
follow the instructions on P. 99 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.

2752-4. Using other driving systems
2
When driving CAUTION■
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 the TRAC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are the systems to help ensure vehicle stability and driving force, do not turn
the TRAC/VSC systems off unless necessary.■
Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
inflation pressure level.
The ABS and VSC systems will not function correctly if different tires are installed
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 a system malfunction.

3032-5. Driving information
2
When driving
Selecting tire chains
Use the correct 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
0.98 in. (25 mm) in length
0.43 in. (10.8 mm) in width
Cross chain:
0.15 in. (3.9 mm) in diameter
1.00 in. (25.3 mm) in length
0.54 in. (13.8 mm) in width
Regulations on the use of tire chains
Regulations regarding the use of tire chains vary depending on location
and type of road. Always check local regulations before installing chains. ■ When driving the vehicle
Accelerate the vehicle slowly, keep a safe distance between you and
the vehicle ahead, and drive at a reduced speed suitable to road
conditions.
■ When parking the vehicle
Park the vehicle and move the shif t lever to P without setting the
parking brake. The parking brake may freeze up, preventing it from
being released. If necessary, bl ock the wheels to prevent inadvert-
ent sliding or creeping.

3042-5. Driving information
■
Tire 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 front tires only. Do not install tire chains on the rear tires.●
Install the tire chains on front tires as tightly as possible. Re tighten chains after
driving 1 /4  1/2 mile (0.5  1.0 km).●
Install tire chains following the instructions provided with the tire chains.
CAUTION■
Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure 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.
Failure 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 acceleration, abrupt stee ring, sudden braking and shifting opera-
tions that cause sudden engine braking.
●
Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.

6714-3. Do-it-yourself maintenance
4
Maintenance and care
Installing tire pressure warning valves and transmitters
When 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 co mputer and the tire pressure warning
system must be initialized. Have tire pressure warning valve and transmit-
ter ID codes registered by your Lexus dealer. (  P. 6 7 3 )
Initializing the tire pressure warning system
■ The tire pressure warning system must be initialized in the following
circumstances:
● When rotating the tires
● When the tire inflation pressure is changed such as when changing
travelling speed or load weight
● When changing the tire size
When the tire pressure warning sy stem is initialized, the current tire
inflation pressure is set as the benchmark pressure.■ The tire pressure warning system
Your Lexus is equipped with a tire pressure warning system that uses
tire pressure warning valves and tr ansmitters to detec t low tire infla-
tion pressure before serious problems arise. (  P. 7 3 6 )

6734-3. Do-it-yourself maintenance
4
Maintenance and care Registering ID codes
The tire pressure warning valve and transmitter is equipped with a unique
ID code. When replacing a tire pressure warning valve and transmitter, it
is necessary to register the ID code. Ha ve the ID code registered by your
Lexus dealer. ■
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, and 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 warn ing 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 on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.■
Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.

6744-3. Do-it-yourself maintenance
■
Maximum load of tire
Check that the number given by dividing the maximum load by 1.10 of the replace-
ment tire is greater than 1 /2 of the Gr oss Axle Weight Ratings (GAWR) of either
the front axle or the rear axle, whichever 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 adequa te traction performance compared with
snow tires in heavy or loos e snow. Also, all 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 local regulations for possible restrictions.
Snow tires should be installed on all wheels. (  P. 3 0 2 )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. 8 1 3 )

6834-3. Do-it-yourself maintenance
4
Maintenance and care Wheels
■
When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning valves and
transmitters that allow the tire pressure warning system to provide advanced warn-
ing in the event of a loss in tire inflation pressure. Whenever wheels are replaced,
tire pressure warning valves and transmitters must be installed. (  P. 6 7 1 )If a wheel is bent, cracked or heavily corroded, it should be replaced.
Otherwise, the tire may separate from the wheel or cause a loss of han-
dling control.
■ Wheel selection
When replacing wheels, care should be taken to ensure that they
are equivalent to those removed in load capaci ty, diameter, rim
width, and inset*.
Replacement wheels are available at your Lexus dealer. *: Conventionally referred to as “offset”.
Lexus does not recommen d using the following:
● Wheels of different sizes or types
● Used wheels
● Bent wheels that have been straightened
■ Aluminum wheel precautions
● Use only Lexus wheel nuts and wrenches designed for use with
your aluminum wheels.
● When rotating, repairing or changi ng 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.

6844-3. Do-it-yourself maintenance
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 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 serviced by your Lexus dealer or other
qualified service shop. In addition, make sure to purchase 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 transmitters may not work properly with non-
genuine wheels.

5
When trouble arises
7395-2. Steps to take in an emergency
■
The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural
air leaks and tire inflation pressure chan ges caused by temperature. In this case,
adjusting the tire inflation pressure will turn off the warning light (after a few min-
utes).■
When a tire is replaced with a spare tire
Vehicles with a compact spare tire
The compact spare tire is not equipped with a tire pressure warning valve and trans-
mitter. If a tire goes flat, the tire pressure warning light will not turn off even though
the flat tire has been replaced with the spare tire. Replace the spare tire with the
repaired tire and adjust the tire inflatio n pressure. The tire pressure warning light
will go off after a few minutes.
Vehicles with a full-size spare tire
The spare tire is also equipped with the tire pressure warning valve and transmitter.
The tire pressure warning light will turn on if the tire inflation pressure of the spare
tire is low. If a tire goes flat, even though the flat tire is replaced with the spare tire,
the tire pressure warning light does not turn off. Replace the spare tire with the
repaired tire and adjust to the proper tire inflation pressure. The tire pressure warn-
ing light will turn off after a few minutes.■
If the tire pressure warning system is not functioning
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.) ●
If tires not equipped with tire pressure warning valves and transmitters are used●
If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer●
If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm 2
or bar) or higher
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●
If electronic devices or facilities using similar radio wave frequencies are nearby
●
If a radio set at similar frequencies is in use in the vehicle
●
If a window tint that affects the radio wave signals is installed
●
If there is a lot of snow or ice on the vehicle, in particular around the wheels or
wheel housings