tire size INFINITI QX50 2023 User Guide

CAUTION
• Do not operate the engine on a free roller
when any of the wheels are raised.
• If you use the free roller, rotate four
wheels with the same speed without
raising any wheels.
• If an AWD warning message is displayed
while driving there may be a malfunction
in the AWD system. Reduce the vehicle
speed immediately and have your vehicle
checked as soon as possible. It is recom-
mended that you visit an INFINITI re-
tailer for this service.
• The powertrain may be damaged if you
continue driving when the AWD tem-
perature or tire size incorrect messages
are displayed.
• If the AWD high temperature message is
displayed while you are driving, pull off
the road in a safe area, and idle the en-
gine. The driving mode will change to
2WD to prevent the AWD system from
malfunctioning. If the warning message
turns off, you can drive again. •
If the tire size incorrect message is dis-
played while you are driving, pull off the
road in a safe area with the engine idling.
Check that all tire sizes are the same,
that the tire pressure is correct and that
the tires are not excessively worn.
• If a warning message continues to be dis-
played after the above operations, have
your vehicle checked as soon as possible.
It is recommended that you visit an
INFINITI retailer for this service.
Starting and driving5-135

•Tire type and condition may also affect
braking effectiveness.
–
When replacing tires, install the speci-fied size of tires on all four wheels.
– When installing a spare tire, make
sure that it is the proper size and type
as specified on the Tire and Loading
Information label. For additional
information, see “Tire and Loading
Information label” (P. 8-29).
–
For additional information, see “Wheels and tires” (P. 8-27).
The ABS controls the brakes so the wheels do
not lock during hard braking or when braking
on slippery surfaces. The system detects the
rotation speed at each wheel and varies the
brake fluid pressure to prevent each wheel
from locking and sliding. By preventing each
wheel from locking, the system helps the
driver maintain steering control and helps to
minimize swerving and spinning on slippery
surfaces.
Using the system
Depress the brake pedal and hold it down.
Depress the brake pedal with firm steady
pressure, but do not pump the brakes. The Anti-lock Braking System will operate to pre-
vent the wheels from locking up. Steer the
vehicle to avoid obstacles.
WARNING
Do not pump the brake pedal. Doing so may
result in increased stopping distances.
Self-test feature
The Anti-lock Braking System (ABS) includes
electronic sensors, electric pumps, hydraulic
solenoids and a computer. The computer has
a built-in diagnostic feature that tests the
system each time you start the engine and
move the vehicle at a low speed in forward or
reverse. When the self-test occurs, you may
hear a “clunk” noise and/or feel a pulsation in
the brake pedal. This is normal and does not
indicate a malfunction. If the computer
senses a malfunction, it switches the ABS off
and illuminates the ABS warning light on the
instrument panel. The brake system then
operates normally but without anti-lock
assistance.
If the ABS warning light illuminates during
the self-test or while driving, have the vehicle
checked. It is recommended that you visit an
INFINITI retailer for this service.
Normal operation
The Anti-lock Braking System (ABS) operates
at speeds above3-6mph(5-10km/h). The
speed varies according to road conditions.
When the ABS senses that one or more
wheels are close to locking up, the actuator
rapidly applies and releases hydraulic pres-
sure. This action is similar to pumping the
brakes very quickly. You may feel a pulsation
in the brake pedal and hear a noise from
under the hood or feel a vibration from the
actuator when it is operating. This is normal
and indicates that the ABS is operating prop-
erly. However, the pulsation may indicate
that road conditions are hazardous and extra
care is required while driving.
BRAKE ASSIST
When the force applied to the brake pedal
exceeds a certain level, the Brake Assist is
activated generating greater braking force
than a conventional brake booster even with
light pedal force.
WARNING
The Brake Assist is only an aid to assist
braking operation and is not a collision
warning or avoidance device. It is the driv-
er’s responsibility to stay alert, drive safely
and be in control of the vehicle at all times.
Starting and driving5-141

Check for and remove objects obstructing
the area around the sonar sensors.
Do not attach stickers (including transparent
material), install accessories or apply addi-
tional paint near the sonar sensors.
Do not strike or damage the area around the
sonar sensors. It is recommended that you
visit an INFINITI retailer if the area around
the sonar sensors is damaged due to a
collision.FREEING A FROZEN DOOR LOCK
To prevent a door lock from freezing, apply
de-icer through the key hole. If the lock be-
comes frozen, heat the key before inserting it
into the key hole, or use the INFINITI Intelli-
gent Key.
ANTIFREEZE
In the winter when it is anticipated that the
temperature will drop below 32°F (0°C),
check the antifreeze to assure proper winter
protection. For additional information, see
“Engine cooling system” (P. 8-4).
BATTERY
If the battery is not fully charged during ex-
tremely cold weather conditions, the battery
fluid may freeze and damage the battery. To
maintain maximum efficiency, the battery
should be checked regularly. For additional
information, see “Battery” (P. 8-12).
DRAINING OF COOLANT WATER
If the vehicle is to be left outside without
antifreeze, drain the cooling system, including
the engine block. Refill before operating the
vehicle. For additional information, see
“Changing engine coolant” (P. 8-5).
TIRE EQUIPMENT
1. SUMMER tires have a tread designed toprovide superior performance on dry
pavement. However, the performance of
these tires will be substantially reduced in
snowy and icy conditions. If you operate
your vehicle on snowy or icy roads,
INFINITI recommends the use of MUD &
SNOW or ALL SEASON TIRES on all four
wheels. It is recommended that you visit
an INFINITI retailer for the tire type, size,
speed rating and availability information.
2. For additional traction on icy roads, stud- ded tires may be used. However, some
U.S. states and Canadian provinces pro-
hibit their use. Check local, state and pro-
vincial laws before installing studded tires.
Skid and traction capabilities of studded
snow tires on wet or dry surfaces may be
poorer than that of non-studded snow tires.
3. Tire chains may be used. For additional information, see “Tire chains”(P. 8-38).
COLD WEATHER DRIVING
Starting and driving5-153

Tire and Loading Information label
1Seating capacity: The maximum
number of occupants that can be
seated in the vehicle.
2Original tire size: The size of the
tires originally installed on the ve-
hicle at the factory.
3Cold tire pressure: Inflate the tires
to this pressure when the tires are
cold. Tires are considered COLD
after the vehicle has been parked
for 3 or more hours, or driven less
than 1 mile (1.6 km) at moderate
speeds. The recommended cold
tire inflation is set by the manufac-
turer to provide the best balance
of tire wear, vehicle handling,
driveability, tire noise, etc., up to
the vehicle's GVWR.
4Tire size - see “Tire labeling”
(P. 8-32).
5Spare tire size.
6Vehicle load limit: see “Vehicle
loading information” (P. 10-17).
LDI3172
Do-it-yourself8-29

Checking tire pressure
WARNING
• Driving at high speeds, 100 mph
(160 km/h) or higher sustained
where it is legal to do so, can cause
tires to have excessive heat build
up, which may result in a tire fail-
ure causing loss of control, crash,
injuries or even death. •
Some high-speed rated tires re-
quire inflation pressure adjust-
ment for high-speed operation.
When speed limits and road condi-
tions allow vehicle driving at high
speeds, make sure tires are rated
to support high speed operation,
tires are in optimal conditions and
pressure is adjusted to correct
cold inflation pressure for high
speed operation.
• If your vehicle is equipped with
P235/55RF19 or P255/45RF20
tire sizes, tires require adjustment
to the inflation pressure when
driving the vehicle at speeds of
100 mph (160 km/h) or higher
where it is legal to do so. Set the
cold inflation pressure to 36 psi
(250 kPa). •
After vehicle high speed operation
has ended, readjust the tire pres-
sure to the recommended cold
inflation pressure. For additional
information, see "Checking tire
pressure" (P. 8-30).
1. Remove the valve stem cap from the tire.
2. Press the pressure gauge squarely onto the valve stem. Do not press
too hard or force the valve stem
sideways, or air will escape. If the
hissing sound of air escaping from
the tire is heard while checking the
pressure, reposition the gauge to
eliminate this leakage.
3. Remove the gauge.
4. Read the tire pressure on the gauge stem and compare to the
specification shown on the Tire
and Loading Information label.
LDI0393
8-30Do-it-yourself

5. Add air to the tire as needed. If toomuch air is added, press the core of
the valve stem briefly with the tip
of the gauge stem to release pres-
sure. Recheck the pressure and add
or release air as needed.
6. Install the valve stem cap.
7. Check the pressure of all other tires, including the spare.
8. Check the pressure when driving the vehicle at speeds of 100 mph
(160 km/h) or higher where it is
legal to do so.Size Cold Tire Inflation
Pressure
psi kPa
Front and
Rear
Original
Tire:
P235/
55RF19 33 230
Front and
Rear
Original
Tire:
P255/
45RF20 33 230
Spare Tire: noneRecommended tire inflation pressures
at speeds of 100 mph (160 km/h) or
higher where it is legal to do so.
Size Cold Tire Inflation
Pressure
psi kPa
Front and
Rear
Original
Tire:
P235/
55RF19 36 250
Front and
Rear
Original
Tire:
P255/
45RF20 36 250
Spare Tire: none
Do-it-yourself8-31

TIRE LABELING
Federal law requires tire manufactur-
ers to place standardized information
on the sidewall of all tires. This infor-
mation identifies and describes the
fundamental characteristics of the tire
and also provides the Tire Identifica-
tion Number (TIN) for safety standard
certification. The TIN can be used to
identify the tire in case of a recall.
O1Tire size (example: P215/65R15
95H)
1. P: The “P” indicates the tire is de- signed for passenger vehicles (not
all tires have this information).
2. Three-digit number (215): This number gives the width in millime-
ters of the tire from sidewall edge
to sidewall edge. 3. Two-digit number (65): This num-
ber, known as the aspect ratio,
gives the tire's ratio of height to
width.
4. R: The “R” stands for radial.
5. Two-digit number (15): This num- ber is the wheel or rim diameter in
inches.
WDI0394
Example
WDI0395
Example
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6. Two- or three-digit number (95):This number is the tire's load index.
It is a measurement of how much
weight each tire can support.
7. H: Tire speed rating. You should not drive the vehicle faster than the tire
speed rating.
O2TIN (Tire Identification Number)
for a new tire (example: DOT XX XX
XXX XXXX)
1. DOT: Abbreviation for the “Depart- ment Of Transportation”. The sym-
bol can be placed above, below or
to the left or right of the Tire Iden-
tification Number.
2. Two-digit code: Manufacturer's identification mark. 3. Two-digit code: Tire size.
4. Three-digit code: Tire type code
(Optional).
5. Four numbers represent the week and year the tire was built. For ex-
ample, the numbers 3103 means
the 31st week of 2003. If these
numbers are missing then look on
the other sidewall of the tire.
LDI2786
Example (Type A) (if so equipped)
Do-it-yourself8-33

O7The word “radial”
The word “radial” is shown if the tire
has radial structure.
O8Manufacturer or brand name
Manufacturer or brand name is
shown.
Other Tire-related Terminology
In addition to the many terms that are
defined throughout this section, In-
tended Outboard Sidewall is (1) the
sidewall that contains a whitewall,
bears white lettering or bears manu-
facturer, brand, and/or model name
molding that is higher or deeper than
the same molding on the other side-
wall of the tire, or (2) the outward
facing sidewall of an asymmetrical tire
that has a particular side that must
always face outward when mounted
on a vehicle.
TYPES OF TIRES
WARNING
• When changing or replacing tires, be sure
all four tires are of the same type (i.e.,
Summer, All Season or Snow) and con-
struction. An INFINITI retailer may be
able to help you with information about
tire type, size, speed rating and
availability.
• Replacement tires may have a lower
speed rating than the factory equipped
tires, and may not match the potential
maximum vehicle speed. Never exceed
the maximum speed rating of the tire.
• Replacing tires with those not originally
specified by INFINITI could affect the
proper operation of the low tire pressure
warning system.
• Always use tires of the same type, size,
brand, construction and tread pattern on
all four wheels. Failure to do so may re-
sult in a circumference difference be-
tween tires on the front and rear axles
which can cause the Vehicle Dynamic
Control (VDC) system to malfunction re-
sulting in personal injury or death, exces-
sive tire wear and may damage the
transmission, transfer case and differen-
tial gears. •
For additional information regarding
tires, refer to “Important Tire Safety In-
formation” (US) or “Tire Safety Informa-
tion” (Canada) in the Warranty Informa-
tion Booklet.
All-Wheel Drive (AWD) models
CAUTION
• ONLY use spare tires specified for the
AWD model.
If excessive tire wear is found, it is recom-
mended that all four tires be replaced with
tires of the same size, brand, construction
and tread pattern. The tire pressure and
wheel alignment should also be checked and
corrected as necessary. It is recommended
that you visit an INFINITI retailer for this
service.
All season tires
INFINITI specifies All Season tires on some
models to provide good performance all year,
including snowy and icy road conditions. All
Season tires are identified by ALL SEASON
and/or M&S on the tire sidewall. Snow tires
have better snow traction than All Season
tires and may be more appropriate in some
areas.
Do-it-yourself8-35

Summer tires
INFINITI specifies summer tires on some
models to provide superior performance on
dry roads. Summer tire performance is sub-
stantially reduced in snow and ice. Summer
tires do not have the tire traction rating
“M&S” on the tire sidewall.
If you plan to operate your vehicle in snowy or
icy conditions, INFINITI recommends the use
of SNOW tires or ALL SEASON tires on all
four wheels.
Snow tires
If snow tires are needed, it is necessary to
select tires equivalent in size and load rating
to the original equipment tires. If you do not,
it can adversely affect the safety and han-
dling of your vehicle.
Generally, snow tires have lower speed rat-
ings than factory equipped tires and may not
match the potential maximum vehicle speed.
Never exceed the maximum speed rating of
the tire.
If you install snow tires, they must be the
same size, brand, construction and tread pat-
tern on all four wheels.
For additional traction on icy roads, studded
tires may be used. However, some U.S. statesand Canadian provinces prohibit their use.
Check local, state and provincial laws before
installing studded tires. Skid and traction ca-
pabilities of studded snow tires on wet or dry
surfaces may be poorer than that of non-
studded snow tires.
Run–flat tires
Your vehicle is equipped with run-flat tires
and is not equipped with a spare tire, or a jack
and tool kit. The jack and tool kit may be
purchased at the dealer. Please consult an
INFINITI retailer for additional information.
You can continue driving to a safe location
even if the run-flat tires are punctured. Al-
ways use run-flat tires of the specified size on
all four wheels. Mixing tire sizes or construc-
tion may reduce vehicle handling stability. If
necessary, it is recommended that you visit an
INFINITI retailer for this service.
Frequently check the tire pressure and adjust
pressure of each tire properly. The tire pres-
sure can be also checked in the vehicle infor-
mation display.
It can be difficult to tell if a run-flat tire is
under-inflated or flat. Check the tire pres-
sures as described in this section. If the tire
becomes under-inflated while driving, the
low tire pressure warning light will illuminate
and the “Tire Pressure Low – Add Air”warning appears in the vehicle information
display. If the tire becomes flat while driving,
the low tire pressure warning light and the
“Flat Tire – Visit dealer" warning will appear.
Low tire pressure:
If the vehicle is being driven with low tire
pressure, the low tire pressure warning light
will illuminate and the “Tire Pressure Low –
Add Air” warning appears in the vehicle infor-
mation display.
Flat tire:
If the vehicle is being driven with one or more
flat tires, the low tire pressure warning light
will illuminate continuously and a chime will
sound for 10 seconds. A “Flat-Tire – Visit
dealer" warning also appears in the vehicle
information display.
The chime will only sound at the first indica-
tion of a flat tire and the warning light will
illuminate continuously. When the flat tire
warning is activated, have the system reset
and the tire checked and replaced if neces-
sary. It is recommended that you visit an
INFINITI retailer for this service. Even if the
tire is inflated to the specified COLD tire
pressure, the warning light will continue to
illuminate until the system is reset. It is recom-
mended that you visit an INFINITI retailer for
this service.
8-36Do-it-yourself