tire size LEXUS UX250H 2019 User Guide

3476-3. Do-it-yourself maintenance
6
Maintenance and care
Rotate the tires in the order shown.
To equalize tire wear and extend tire life,
Lexus recommends that tire rotation is car-
ried out at the same interval as tire inspec-
tion.
Do not fail to initialize the tire pressure
warning system after tire rotation.
■When rotating the tires
Make sure that the powe r switch is OFF. If
the tires are rotated while the power switch
is in ON, the tire position information will
not be updated.
If this accidentally occurs, either turn the
power switch to OFF and then to ON, or
initialize the tire pressure warning system
after checking that the tire pressure is prop-
erly adjusted.
When run-flat tires are installed, the
vehicle can be driven for a maximum of
100 miles (160 km) at a speed below
50 mph (80 km/h) after any tire goes
flat. (However, the vehicle speed may
not increase to near 50 mph [80
km/h] depending on weather or driv-
ing conditions.)
A run-flat tire has a mark on
the sidewall.
Make sure to replace the flat tire before the
vehicle has been driven for near 100 miles
(160 km). Also, do not use a repaired tire.
WARNING
■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 danger-
ous handling 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-b elted 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.
NOTICE
■Driving on rough roads
Take particular care when driving on
roads with loose surfaces or potholes.
These conditions may cause losses in tire
inflation pressure, reducing the cushion-
ing ability of the tires. In addition, driving
on rough roads may cause damage to
the tires themselves, as well as the vehi-
cle’s wheels and body.
Tire rotation
Run-flat tires

3486-3. Do-it-yourself maintenance
■Run-flat tires
●The run-flat tires are for only this vehicle.
Do not use the tires on other vehicles.
●Do not mix run-flat tires and normal tires.
●If non-genuine Lexus wheels are used, it
may be impossible to sufficiently demon-
strate the performance of run-flat tires.
Your vehicle is equipped with a tire
pressure warning system that uses tire
pressure warning valves and transmit-
ters to detect low tire inflation pressure
before serious problems arise.
If the tire pressure drops below a
predetermined level, the driver is
warned by a screen display and a
warning light. ( P.387, 395)
 The tire pressure detected by the
tire pressure warning system can be
displayed on the multi-information
display. ( P.87)
The illustration used is intended as an
example, and may differ from the image
that is actually displayed on the multi-infor-
mation display.
■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.
■Tire inflation pressure
●It may take a few minutes to display the
tire inflation pressu
re after the power
switch is turned to ON. It may also take a
few minutes to display the tire inflation
pressure after inflatio n pressure has been
adjusted.
●Tire inflation pressure changes with tem-
perature. The displaye d values may also
be different from the values measured
using a tire pressure gauge.
■Situations in which the tire pressure
warning system may not operate prop-
erly
●In the following cases, the tire pressure
warning system may not operate prop-
erly.
• 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.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the 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 extremely higher than the specified level.
• If wheels without tire pressure warning
valves and transmitters are used.
• If the ID code on the tire pressure warn- ing valves and transmitters is not regis-
tered in the tire pressure warning
computer.
●Performance may be af fected in the fol-
lowing situations.
• Near a TV tower, electric power plant,
gas station, radio stat ion, large display,
airport or other fac ility that generates
strong radio waves or electrical noise
• When carrying a portable radio, cellular
phone, cordless phone or other wireless
communication device
If tire position information is not correctly
displayed due to the radio wave conditions,
Tire pressure warning system

3516-3. Do-it-yourself maintenance
6
Maintenance and care
■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 tire
size. (When there are multiple spec-
ified pressures)
 After registering the ID codes.
( P.352)
When the tire pressure warning system
is initialized, the current tire inflation
pressure is set as the benchmark pres-
sure.
■How to initialize the tire pressure
warning system
1
Park the vehicle in a safe place and
stop the hybrid system for 20 min-
utes or more.
Initialization cannot be performed while
the vehicle is moving.
2Adjust the tire inflation pressure to
the specified cold tire inflation pres-
sure level.
Make sure to adjust the tire pressure to the
specified cold tire inflation pressure level.
The tire pressure warning system will oper-
ate based on this pressure level.
3Start the hybrid system ( P.162)
4
Press or of the meter con-
trol switches and select .
5
Press or of the meter con-
trol switches and select “Vehicle
Settings”, then press “OK”.
6
Press or of the meter con-
trol switches and select “TPWS”,
then press “OK”.
7
Press or of the meter con-
trol switches and select “Set Pres-
sure”. Then press and hold “OK”
until the tire pressure warning light
starts blinking.
A message is displayed on the multi-infor-
mation display. Also, “--” is displayed for
inflation pressure of each tire on the multi-
information display while the tire pressure
warning system determines the position.
8Drive at approximately 25 mph
(40 km/h) or more for approxi-
mately 10 to 30 minutes.
When initialization is complete, the infla-
tion pressure of each tire will be displayed
on the multi-information display.
Even if the vehicle is not driven at approxi-
mately 25 mph (40 km/h) or more, initial-
NOTICE
■To avoid damage to the tire pressure
warning valves and transmitters
When a tire is repaired with liquid seal-
ants, the tire pressure warning valve and
transmitter may not operate properly. If a
liquid sealant is used , contact your Lexus
dealer or other qualified service shop as
soon as possible. After use of liquid seal-
ant, make sure to re place the tire pres-
sure warning valve and transmitter when
repairing or replacing the tire.
Initializing the tire pressure
warning system

3616-3. Do-it-yourself maintenance
6
Maintenance and care
The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
( P.422)
Tire valve Tire pressure gauge
1 Remove the tire valve cap.
2 Press the tip of the tire pressure
gauge onto the tire valve.
3 Read the pressure using the gauge
gradations.
4 If the tire inflation pressure is not at
the recommended level, adjust the
pressure.
If you add too much air, press the
center of the valve to deflate.
5 After completing the tire inflation
pressure measurement and adjust-
ment, apply soapy water to the
valve and check for leakage.
6 Put the tire valve cap back on.
■Tire inflation pressure check interval
You should check tire inflation pressure
every two weeks, or at least once a month.
Do not forget to check the spare.
■Effects of incorrect tire inflation pres-
sure
Driving with incorrect ti re inflation pressure
may result in the following:
●Reduced fuel economy
●Reduced driving comfort and poor han-
dling
●Reduced tire life due to wear
●Reduced safety
●Damage to the drive train
If a tire needs frequent inflating, have it
checked by your Lexus dealer.
■Instructions for checking tire inflation
pressure
When checking tire inflation pressure,
observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at
least 3 hours or has not been driven for
Tire inflation pressure
Checking the specified tire infla-
tion pressure
Inspection and adjustment pro-
cedure
A
B

3636-3. Do-it-yourself maintenance
6
Maintenance and care
When replacing wheels, care should
be taken to ensure that they are equiv-
alent to those removed in load capac-
ity, 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 straight-
ened
■When replacing wheels
The wheels of your vehicle are equipped
with tire pressure warning valves and trans-
mitters 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 pres-
sure warning valves an d transmitters must
be installed. ( P.350) Use only Lexus wheel nuts and
wrenches designed for use with
your aluminum wheels.
 When rotating, repairing or chang-
ing your tires, check that the wheel
nuts are still tight after driving 1000
miles (1600 km).
 Be careful not to damage the alumi-
num wheels when using tire chains.
 Use only Lexus genuine balance
weights or equivalent and a plastic
or rubber hammer when balancing
your wheels.
Wheels
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
handling control.
Wheel selection
WARNING
■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 acci-
dent, 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
during driving, possibly causing an acci-
dent.
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 qua lified 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 trans-
mitters may not work properly with
non-genuine wheels.
Aluminum wheel precautions

3947-2. Steps to take in an emergency
WARNING
●If the tire pressure warning light comes
on even after tire inflation pressure
adjustment, it is probable that you have
a flat tire. Have the flat tire replaced by
the nearest Lexus dealer.
●Avoid abrupt maneuvering and brak-
ing.
If the vehicle tires deteriorate, you
could lose control of the steering
wheel or the brakes.
■If a blowout or sudden air leakage
should occur
The tire pressure warning system may
not activate immediately.
■Maintenance of the tires
Each tire, including the spare (if pro-
vided), should be checked monthly when
cold and inflated to the inflation pressure
recommended by the vehicle manufac-
turer on the vehicle placard or tire infla-
tion pressure label (tire and load
information label). (If your vehicle has
tires of a different size than the size indi-
cated on the vehicle placard or tire infla-
tion pressure label [tire and load
information label], yo u should determine
the proper tire infl ation pressure for
those tires.)
As an added safety feature, your vehicle
has been equipped with a tire pressure
monitoring system (TPMS-tire pressure
warning system) that illuminates a low
tire pressure telltale (tire pressure warn-
ing light) when one or more of your tires
is significantly under-inflated. Accord-
ingly, when the low tire pressure telltale
(tire pressure warnin g light) illuminates,
you should stop and check your tires as
soon as possible, and inflate them to the
proper pressure. Driving on a signifi-
cantly under-inflated tire causes the tire
to overheat and can lead to tire failure.
Under-inflation also reduces fuel effi-
ciency and tire tread life, and may affect
the vehicle’s handling and stopping abil-
ity.
Please note that the TPMS (tire pressure
warning system) is not a substitute for
proper tire maintenance, and it is the
driver’s responsibility to maintain correct
tire pressure, even if under-inflation has
not reached the level to trigger illumina-
tion of the TPMS low tire pressure telltale
(tire pressure warning light).
Your vehicle has also been equipped with
a TPMS (tire pressure warning system)
malfunction indicator to indicate when
the system is not operating properly. The
TPMS (tire pressure warning system)
malfunction indicator is combined with
the low tire pressure telltale (tire pres-
sure warning light) . When the system
detects a malfunction, the telltale will
flash for approximately one minute and
then remain continuously illuminated.
This sequence will continue upon subse-
quent 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)
malfunctions 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 func-
tioning 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
pressure warning system) to continue to
function properly.
NOTICE
■To ensure the tire pressure warning
system operates properly
Do not install tires with different specifi-
cations or makers, as the tire pressure
warning system may not operate prop-
erly.

4228-1. Specifications
A: Wedge base bulbs (amber)
B: Wedge base bulbs (clear)
Tires and wheels
Tire size225/50RF18 95V
Tire inflation pressure
(Recommended cold tire inflation
pressure)Front: 33 psi (230 kPa, 2.3 kgf/cm2 or bar)
Rear: 33 psi (230 kPa, 2.3 kgf/cm
2 or bar)
Wheel size18  7 J
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)
Light bulbs
Light bulbsBulb No.WType
ExteriorFront turn signal lights (vehicles
with single-beam headlights)WY21W21A
InteriorVanity lights8B

4258-1. Specifications
8
Vehicle specifications
Tire size (P.426)
Run-flat tire (RFT) or standard tire ( P.399)
This vehicle can be equipped with either run-flat tires (RFT) or standard tires. A
mark is molded on the sidewall of the run-flat tire.
DOT and Tire Identification Number (TIN) ( P.426)
Location of treadwear indicators ( P.345)
Tire ply composition and materials
Plies are layers of rubber-coated parallel cords. Cords are the strands which form the plies
in a tire.
Radial tires or bias-ply tires
A radial tire has “RADIAL” on the sidewall. A tire not marked “RADIAL” is a bias-ply tire.
TUBELESS or TUBE TYPE
A tubeless tire does not have a tube and air is directly put into the tire. A tube type tire has a
tube inside the tire and the tube maintains the air pressure.
Load limit at maximum cold tire inflation pressure ( P.429)
Maximum cold tire inflation pressure ( P.429)
This means the pressure to which a tire may be inflated.
Uniform tire quality grading
For details, see “Uniform Tire Quality Grading” that follows.
Tire information
Typical tire symbols
A
B
C
D
E
F
G
H
I
J

4268-1. Specifications
Summer tires or all season tires (P.346)
An all season tire has “M+S” on the sidewall. A tire not marked “M+S” is a summer tire.
Type A
DOT symbol
*
Tire Identification Number (TIN)
Tire manufacturer’s identification
mark
Tire size code
Manufacturer’s optional tire type
code (3 or 4 letters)
Manufacturing week
Manufacturing year
*:The DOT symbol cert ifies that the tire
conforms to applicable Federal Motor
Vehicle Safety Standards.
Type B
DOT symbol
*
Tire Identification Number (TIN)
Tire manufacturer’s identification
mark
Manufacturer’s code
Manufacturing week
Manufacturing year
*: The DOT symbol certifies that the tire conforms to applicable Federal Motor
Vehicle Safety Standards.
■Typical tire size information
The illustration indicates typical tire
size.
K
Typical DOT and Tire Identifica-
tion Number (TIN)
A
B
C
D
E
F
GTire size
A
B
C
D
E
F

4308-1. Specifications
Rim size designationRim diameter and width
Rim type designationThe industry manufacturer’s designation for a rim by style or
code
Rim widthNominal distance between rim flanges
Vehicle capacity weight
(Total load capacity)The rated cargo and luggage load plus 150 lb. (68 kg) times
the vehicle’s designated seating capacity
Vehicle maximum load on
the tireThe load on an individual tire that is determined by distribut-
ing to each axle its share of the maximum loaded vehicle
weight, and dividing by two
Vehicle normal load on the
tire
The load on an individual tire that is determined by distribut-
ing to each axle its share of curb weight, accessory weight,
and normal occupant weight (distributed in accordance with
Table 1
* below), and dividing by two
Weather sideThe surface area of the rim not covered by the inflated tire
BeadThe part of the tire that is ma de of steel wires, wrapped or
reinforced by ply cords and th at 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 compounds
CrackingAny parting within the tread, side wall, 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 wi th 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 tireA tire designed to operate at higher loads and at higher
inflation pressures than the corresponding standard tire
Tire related termMeaning