tire size LEXUS RX450h 2018 User Guide

612 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85UYour vehicle is equipped with a tire pressure warning system that uses tire pres-
sure warning valves and transmitters to detect low tire inflation pressure before
serious problems arise.
◆ Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pr essure warning valv es and transmitters
must also be installed.
When new tire pressure wa rning valves and transmitters are installed, new ID
codes must be registered in the tire pressure warning computer and the tire
pressure warning system must be initia lized. Have tire pressure warning valve
and transmitter ID codes registered by your Lexus dealer. ( → P. 613)
◆ Initializing the tire pressure warning system ■
The tire pressure warning system must be initialized in the following circum-
stances: ●
When the tire inflation pressure is changed such as when changing travel-
ing speed. ●
When the tire inflation pressure is changed such as when the tire size is
changed. ●
When rotating the tires
When the tire pressure warning system is initialized, the current tire inflation
pressure is set as the benchmark pressure.Tire pressure warning system ●
The tire pressure detected by the tire
pressure warning system can be dis-
played on the multi-information display. The illustration used is intended as an exam-
ple, and may differ from the image that is
actually displayed on the multi-information
display.●
If the tire pressure drops below a prede-
termined level, the driver is warned by a
screen display and a warning light.
( → P. 662) The illustration used is intended as an exam-
ple, and may differ from the image that is
actually displayed on the multi-information
display.

614 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85U■
When to replace your vehicle’s tires
Tires should be replaced if: ●
The treadwear indicators are showing on a tire. ●
You have tire damage such as cuts, splits, cracks deep enou gh 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 warning valve and transmitter is not registered, the tire
pressure warning system will not work proper ly. After driving for about 20 minutes, the
tire pressure warning light blinks for 1 minu te and stays on to indicate a system malfunc-
tion. ■
Tire life
Any tire over 6 years old must be checked by a qualified technician even if it has seldom
or never been used or damage is not obvious.■
Proper storage of the spare tire (RX450hL)
As an improperly stored spare tire may cause damage to the wire cable that holds it,
check that the spare tire is stored properly on a daily basis.
If the spare tire is slanted, the hoist assemb ly may be stuck in the wheel opening. If the
spare tire rattles while driving, it may not be fully raised. Lower the spare tire to the
ground and make sure that the hoist assemb ly is perpendicular to the wheel opening.
Raise the tire slowly and steadily until a click is heard and the jack handle skips.
If the spare tire cannot be lowered, the wire cable may be severed. Have the vehicle
inspected at your Lexus dealer. ■
Routine tire inflation pressure checks
The tire pressure warning syst em does not replace routine tire inflation pressure checks.
Make sure to check tire inflat ion pressure as part of your routine of daily vehicle checks.●
If the stored spare tire appears to be slanted or
rattles while driving, the spare tire may not be
properly stored. Store the spare tire again by
performing the following tire change proce-
dure correctly: 1
2

6157-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85U■
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, whichever is
greater.
■
Tire types ●
Summer tires
Summer tires are high-speed performance ti res best suited to highway driving under
dry conditions. Since summer tires do not have the same traction performance as
snow tires, summer tires are inadequate for driving on snow-covered or icy roads. For
driving on snow-covered roads or icy road s, the use of snow tires is recommended.
When installing snow tires, be sure to replace all four tires.●
All season tires
All season tires are designed to provide better traction in snow and to be adequate for
driving in most winter conditions as well as for use year-round. All season tires, how-
ever, do not have adequate traction perfor mance compared with snow tires in heavy
or loose snow. Also, all season tires fall short in acceleration and handling perfor-
mance compared with summer tires in highway driving.●
Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires. If
you need snow tires, select ti res of the same size, construction and load capacity as the
originally installed tires. Since your vehicle has radial tires as or iginal equipment, make
sure your snow tires also have radial cons truction. Do not install studded tires without
first checking local regulations for possible restrictions. Snow tires should be installed
on all wheels. ( → P. 390)■
Initializing the tire pressure warning system
Initialize the system with the tire inflation pressure adjusted to the specified level.■
If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tire s as snow tires is lost.■
If you press the tire pressure warning reset switch accidentally
If initialization is performed, adjust the tire inflation pressure to the specified level and ini-
tialize the tire pressure warning system again. For the GAWR, see the Ce rtification Label. For
the maximum load of the tire, see the load limit
at maximum cold tire inflation pressure men-
tioned on the sidewall of the tire. ( → P. 723)

616 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85U■
Situations in which the tire pressure warning system may not operate properly ●
In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains, etc. are equipped.
• If a window tint that affects th e radio wave signals is installed.
• If there is a lot of snow or ice on the vehi cle, particularly around the wheels or wheel
housings.
• If the tire inflation pressure is extr emely higher than the specified level.
• If wheel without the tire pressure warning valve and transmitter is used.
• If the ID code on the tire pressure warning valves and transmitters is not registered
in the tire pressure warning computer. ●
Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air-
port or other facility that generates st rong radio waves or electrical noise.
• When carrying a portable radio, cellular phone, cordless phon e or other wireless
communication device.
If tire position information is not correctl y displayed due to the radio wave conditions,
the display may be corrected by driving and changing the radio wave conditions. ●
When the vehicle is parked, the time taken for the warning to start or go off could be
extended. ●
When tire inflation pressure declines rapidly for example when a tire has burst, the
warning may not function. ■
The initialization operation ●
Make sure to carry out initialization afte r adjusting the tire inflation pressure.
Also, make sure the tires are cold before carryi ng out initialization or tire inflation pres-
sure adjustment. ●
If you have accidentally turned the power switch off during in itialization, it is not neces-
sary to press the reset switch again as initialization will re start automatically when the
power switch has been turned to ON mode for the next time. ●
If you accidentally press the re set switch when initialization is not necessary, adjust the
tire inflation pressure to the specified leve l when the tires are co ld, and conduct initial-
ization again. ●
While the position of each tire is being de termined and the inflation pressures are not
being displayed on the multi-info rmation display, if the inflat ion pressure of a tire drops,
the tire pressure warning light will come on.

6197-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85UWARNING ■
When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as dangerous han-
dling characteristics, which may lead to an accident resu lting 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 be en 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 initializing tire inflatio n pressure 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 pressure is low, or it may come on when the tire inflation pressure is
actually normal.
NOTICE ■
Repairing or replacing tires, wheels, tire pressure warning valv es, transmitters and
tire valve caps ●
When removing or fitting the wheels, tires or the tire pressure warning valves and
transmitters, contact your Lexus dealer as the tire pressure warning valves and trans-
mitters may be damaged if not handled correctly. ●
Make sure to install the tire valve caps. If the tire valve caps ar e not installed, water
could enter the tire pressure warning valves and the tire pressure warning valves
could be bound. ●
When replacing tire valve caps, do not use tire valve caps other than those specified.
The cap may become stuck. ■
To avoid damage to the tire pressu re warning valves and transmitters
When a tire is repaired with liquid sealants, the tire pressure warning valve and trans-
mitter may not operate properly. If a liquid sealant is used, contact your Lexus dealer or
other qualified service shop as soon as possi ble. Make sure to replace the tire pressure
warning valve and transmitter when replacing the tire. ( → P. 612)■
Driving on rough roads
Take particular care when driving on roads with loose surfaces or potholes.
These conditions may cause lo sses in tire inflation pre ssure, reducing the cushioning
ability of the tires. In addition, driving on rough roads may cause damage to the tires
themselves, as well as the vehicle’s wheels and body. ■
If tire inflation pressure of ea ch tire becomes low while driving
Do not continue driving, or your tires and/or wheels may be ruined.

620 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85UThe recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
( → P. 717)
Tire inflation pressure Tire inflation pressure

6237-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85UWhen replacing wheels, care should be ta ken 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 referre d 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. 612)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

624 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85UWARNING ■
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. ■
Use of defective wheels prohibited
Do not use cracked or deformed wheels.
Doing so could cause the tire to leak air du ring driving, possibly causing an accident.
NOTICE ■
Replacing tire pressure warn ing valves and transmitters●
Because tire repair or replacement may affe ct the tire pressure warning valves and
transmitters, make sure to have tires serviced by your Lexus dealer or other qualified
service shop. In addition, ma ke sure to purchase your tire pressure warning valves
and transmitters at your Lexus dealer. ●
Ensure that only genuine Lexus wh eels are used on your vehicle.
Tire pressure warning valves and transmitte rs may not work properly with non-genu-
ine wheels. ■
Selectable Color Trim (if equipped) ●
If rattles, noise, or ot her problems occur while
Selectable Color Trim are installed, contact
your Lexus dealer. ●
Do not remove or install Selectable Color
Trim yourself, as it may be damaged. Have the
Selectable Color Trim removed and installed
by your Lexus dealer.

666 8-2. Steps to take in an emergency
RX450h_RX450hL _U_OM48F85UWARNING ■
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 label (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 ha s 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 st op and check your tires as soon as possible, and inflate
them to the proper pressure. Driving on a si gnificantly under-inflat ed tire causes the
tire to overheat and can lead to tire failure . Under-inflation also reduces fuel efficiency
and tire tread life, and may 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 th e driver’s responsibility to ma intain correct tire pressure,
even if under-inflation has not reached the le vel to trigger illumina tion of the TPMS low
tire pressure telltale (tir e 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 mi nute and then remain continuously illumi-
nated. This sequence will cont inue upon subsequent vehicl e start-ups as long as the
malfunction exists. When the malfunction in dicator 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 system) 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 pressu re 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.

7179-1. Specifications
9
Vehicle specifications
RX450h_RX450hL _U_OM48F85U 
Type ASteering Free play Less than 1.2 in. (30 mm)
Tires and wheels Tire size 235/65R18 106V, T165/90D18 107M (spare)
Tire inflation pressure
(Recommended cold tire
inflation pressure) Front tire
33 psi (230 kPa, 2.3 kgf/cm 2
or bar)
Rear tire
33 psi (230 kPa, 2.3 kgf/cm 2
or bar)
Spare tire
60 psi (420 kPa, 4.2 kgf/cm 2
or bar)
Driving at high speeds (above 100 mph [160 km/h])
(in countries where such speeds are permitted by
law)
Add 5 psi (30 kPa, 0.3 kgf/cm 2
or bar) to the
front and rear tires. Never exceed the maximum
cold tire inflation pressu re indicated on the tire
sidewall.
Wheel size 18 × 8 J, 18 × 4 T (spare)
Wheel nut torque 76 ft•lbf (103 N•m, 10.5 kgf•m)