2018 Hyundai Ioniq Plug-in Hybrid tire pressure

7-35
7
Maintenance
All specifications (sizes and pres-
sures) can be found on a label
attached to the driver's side center
pillar.
Recommended Cold Tire
Inflation Pressures
All tire pressures (including the
spare) should be checked when the
tires are cold. "Cold tires" means the
vehicle has not been driven for at
least three hours or has been driven
less than one mile (1.6 km).
Warm tires normally exceed recom-
mended cold tire pressures by 4 to 6
psi (28 to 41 kPa). Do not release air
from warm tires to adjust the pres-
sure or the tires will be under-inflat-
ed. For recommended inflation pres-
sure, refer to "Tire and Wheels" in
chapter 8.Recommended pressures must
be maintained for the best ride,
vehicle handling, and minimum
tire wear.
Over-inflation or under-inflation
can reduce tire life, adversely
affect vehicle handling, and
lead to sudden tire failure that
could result in loss of vehicle
control resulting in an accident.
Severe under-inflation can lead
to severe heat build-up, causing
blowouts, tread separation and
other tire failures that can result
in the loss of vehicle control
resulting in an accident. This
risk is much higher on hot days
and when driving for long peri-
ods at high speeds.
WARNING
OAE086002L

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Maintenance
Check Tire Inflation Pressure
Check your tires, including the spare
tire, once a month or more.
How to check
Use a good quality tire pressure
gauge to check tire pressure. You
can not tell if your tires are properly
inflated simply by looking at them.
Radial tires may look properly inflat-
ed when they are under-inflated.
Remove the valve cap from the tire
valve stem. Press the tire gauge firm-
ly onto the valve to get a pressure
measurement. If the cold tire inflation
pressure matches the recommended
pressure on the tire label located on
the driver's side center pillar or in this
manual. No further adjustment is
necessary. If the pressure is low, add
air until you reach the recommended
pressure. Make sure to put the valve
caps back on the valve stems.
Without the valve cap, dirt or mois-
ture could get into the valve core and
cause air leakage. If a valve cap is
missing, install a new one as soon as
possible.If you overfill the tire, release air by
pushing on the metal stem in the
center of the tire valve. Recheck the
tire pressure with the tire gauge. Be
sure to put the valve caps back on
the valve stems. Without the valve
cap, dirt or moisture could get into
the valve core and cause air leakage.
If a valve cap is missing, install a new
one as soon as possible.
A cold tire means the vehicle has
been sitting for 3 hours and driven for
less than 1 mile (1.6 km) in that 3
hour period.
Allow the tire to cool before measur-
ing the inflation pressure. Always be
sure the tire is cold before inflating to
the recommended pressure.
Under-inflation results in
excessive wear, poor handling
and reduced fuel economy.
Wheel deformation is also
possible. Keep your tire pres-
sures at the proper levels. If a
tire frequently needs refilling,
have it checked by an author-
ized HYUNDAI dealer.
Over-inflation produces a
harsh ride, excessive wear at
the center of the tire tread,
and a greater possibility of
damage from road hazards.
CAUTION

7-37
7
Maintenance
Tire Rotation
To equalize tread wear, HYUNDAI
recommends that the tires be rotated
every 7,500 miles (12,000 km) or
sooner if irregular wear develops.
During rotation, check the tires for
correct balance.
When rotating tires, check for uneven
wear and damage. Abnormal wear is
usually caused by incorrect tire pres-
sure, improper wheel alignment, out-
of-balance wheels, severe braking or
severe cornering. Look for bumps or
bulges in the tread or side of the tire.
Replace the tire if you find any of
these conditions. Replace the tire if
fabric or cord is visible. After rotation,
be sure to bring the front and rear tire
pressures to specification and check
lug nut tightness (proper torque is
79~94 lbf·ft [11~13 kgf·m]).Disc brake pads should be inspected
for wear whenever tires are rotated.
Information
Tires that are asymmetrical or direc-
tional can only be installed on the
wheel in one direction. The outside
and inside of an asymmetrical tire is
not easily distinguishable. Pay careful
attention to the markings on the side-
walls of the tires, noting the "outside"
marking and also the rotating direc-
tion before installing them on the
vehicle.
i
Do not use the compact spare
tire for tire rotation.
Do not mix bias ply and radial
ply tires under any circum-
stances. This may cause
unusual handling characteris-
tics that may cause loss of
vehicle control resulting in an
accident.
WARNING
ODH073802
■
Without a spare tire

7-42
Maintenance
4. Tire ply composition andmaterial
The number of layers or plies of rub-
ber-coated fabric in the tire. Tire
manufacturers also must indicate the
materials in the tire, which include
steel, nylon, polyester, and others.
The letter "R" means radial ply con-
struction; the letter "D" means diago-
nal or bias ply construction; and the
letter "B" means belted-bias ply con-
struction.
5. Maximum permissible infla-tion pressure
This number is the greatest amount
of air pressure that should be put in
the tire. Do not exceed the maximum
permissible inflation pressure. Refer
to the Tire and Loading Information
label for recommended inflation
pressure.
6. Maximum load rating
This number indicates the maximum
load in kilograms and pounds that
can be carried by the tire. When
replacing the tires on the vehicle,
always use a tire that has the same
load rating as the factory installed
tire.
7. Uniform tire quality grading
Quality grades can be found where
applicable on the tire sidewall
between tread shoulder and maxi-
mum section width.
For example:
TREADWEAR 200
TRACTION AA
TEMPERATURE A
Tread wear
The tread wear grade is a compara-
tive rating based on the wear rate of
the tire when tested under controlled
conditions on a specified govern-
ment test course. For example, a tire
graded 150 would wear one-and-a-
half times (1½) as well on the gov-
ernment course as a tire graded 100.
The relative performance of tires
depends upon the actual conditions
of their use, however, and may
depart significantly from the norm
due to variations in driving habits,
service practices and differences in
road characteristics and climate.
These grades are molded on the
sidewalls of passenger vehicle tires.
The tires available as standard or
optional equipment on your vehicle
may vary with respect to grade.

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Maintenance
Tire Terminology and
Definitions
Air Pressure
The amount of air inside the tire
pressing outward on the tire. Air
pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
This means the combined weight of
optional accessories. Some exam-
ples of optional accessories are
automatic transmission, power
seats, and air conditioning.
Aspect Ratio
The relationship of a tire's height to
its width.
Belt
A rubber coated layer of cords that is
located between the plies and the
tread. Cords may be made from steel
or other reinforcing materials.
Bead
The tire bead contains steel wires
wrapped by steel cords that hold the
tire onto the rim.
Bias Ply Tire
A pneumatic tire in which the plies
are laid at alternate angles less than
90 degrees to the centerline of the
tread.
Cold Tire Pressure
The amount of air pressure in a tire,
measured in pounds per square inch
(psi) or kilopascals (kPa) before a tire
has built up heat from driving.
Curb Weight
This means the weight of a motor
vehicle with standard and optional
equipment including the maximum
capacity of fuel, oil and coolant, but
without passengers and cargo.
DOT Markings
A code molded into the sidewall of a
tire signifying that the tire is in com-
pliance with the U.S. Department of
Transportation motor vehicle safety
standards. The DOT code includes
the Tire Identification Number (TIN),
an alphanumeric designator which
can also identify the tire manufactur-
er, production plant, brand and date
of production.
GVWR
Gross Vehicle Weight Rating
GAWR FRT
Gross Axle Weight Rating for the
Front Axle.
GAWR RR
Gross Axle Weight Rating for the
Rear axle.
Intended Outboard Sidewall
The side of an asymmetrical tire, that
must always face outward when
mounted on a vehicle.

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7
Maintenance
Kilopascal (kPa)
The metric unit for air pressure.
Light truck(LT) tire
A tire designated by its manufacturer
as primarily intended for use on light-
weight trucks or multipurpose pas-
senger vehicles.
Load ratings
The maximum load that a tire is rated
to carry for a given inflation pressure.
Load Index
An assigned number ranging from 1
to 279 that corresponds to the load
carrying capacity of a tire.
Maximum Inflation Pressure
The maximum air pressure to which
a cold tire may be inflated. The max-
imum air pressure is molded onto the
sidewall.
Maximum Load Rating
The load rating for a tire at the maxi-
mum permissible inflation pressure
for that tire.
Maximum Loaded VehicleWeight
The sum of curb weight; accessory
weight; vehicle capacity weight; and
production options weight.
Normal Occupant Weight
The number of occupants a vehicle
is designed to seat multiplied by 150
pounds (68 kg).
Occupant Distribution
Designated seating positions.
Outward Facing Sidewall
An asymmetrical tire has a particular
side that faces outward when mount-
ed on a vehicle. The outward facing
sidewall bears white lettering or
bears manufacturer, brand, and/or
model name molding that is higher or
deeper than the same moldings on
the inner facing sidewall.
Passenger (P-Metric) tire
A tire used on passenger cars and
some light duty trucks and multipur-
pose vehicles.
Ply
A layer of rubber-coated parallel
cords.
Pneumatic tire
A mechanical device made of rubber,
chemicals, fabric and steel or other
materials, that, when mounted on an
automotive wheel provides the trac-
tion and contains the gas or fluid that
sustains the load.
Pneumatic options weight
The combined weight of installed
regular production options weighing
over 5 lb. (2.3 kg) in excess of the
standard items which they replace,
not previously considered in curb
weight or accessory weight, includ-
ing heavy duty breaks, ride levelers,
roof rack, heavy duty battery, and
special trim.

7-46
Maintenance
Recommended InflationPressure
Vehicle manufacturer's recommend-
ed tire inflation pressure as shown
on the tire placard.
Radial Ply Tire
A pneumatic tire in which the ply
cords that extend to the beads are
laid at 90 degrees to the centerline of
the tread.
Rim
A metal support for a tire and upon
which the tire beads are seated.
Sidewall
The portion of a tire between the
tread and the bead.
Speed Rating
An alphanumeric code assigned to a
tire indicating the maximum speed at
which a tire can operate.
Traction
The friction between the tire and the
road surface. The amount of grip pro-
vided.
Tread
The portion of a tire that comes into
contact with the road.
Treadwear Indicators
Narrow bands, sometimes called
"wear bars", that show across the
tread of a tire when only 1/16 inch of
tread remains.
UTQGS
Uniform Tire Quality Grading
Standards is a tire information sys-
tem that provides consumers with
ratings for a tire's traction, tempera-
ture and treadwear. Ratings are
determined by tire manufacturers
using government testing proce-
dures. The ratings are molded into
the sidewall of the tire.
Vehicle Capacity Weight
The number of designated seating
positions multiplied by 150 lbs. (68
kg) plus the rated cargo and luggage
load.
Vehicle Maximum Load on theTire
Load on an individual tire due to curb
and accessory weight plus maximum
occupant and cargo weight.
Vehicle Normal Load on the Tire
Load on an individual tire that is
determined by distributing to each
axle its share of the curb weight,
accessory weight, and normal occu-
pant weight and dividing by 2.
Vehicle Placard
A label permanently attached to a
vehicle showing the original equip-
ment tire size and recommended
inflation pressure.

7-47
7
Maintenance
All Season Tires
HYUNDAI specifies all season tires
on some models to provide good
performance for use all year round,
including snowy and icy road condi-
tions. All season tires are identified
by ALL SEASON and/or M+S (Mud
and Snow) on the tire sidewall. Snow
tires have better snow traction than
all season tires and may be more
appropriate in some areas.
Summer Tires
HYUNDAI specifies summer tires on
some models to provide superior
performance on dry roads. Summer
tire performance is substantially
reduced in snow and ice. Summer
tires do not have the tire traction rat-
ing M+S (Mud and Snow) on the tire
side wall. If you plan to operate your
vehicle in snowy or icy conditions,
HYUNDAI recommends the use of
snow tires or all season tires on all
four wheels.
Snow Tires
If you equip your car with snow tires,
they should be the same size and
have the same load capacity as the
original tires. Snow tires should be
installed on all four wheels; other-
wise, poor handling may result. Snow
tires should carry 4 psi (28 kPa)
more air pressure than the pressure
recommended for the standard tires
on the tire label on the driver’s side of
the center pillar, or up to the maxi-
mum pressure shown on the tire
sidewall, whichever is less. Do not
drive faster than 75 mph (120 km/h)
when your vehicle is equipped with
snow tires.
Radial-Ply Tires
Radial-ply tires provide improved
tread life, road hazard resistance and
smoother high speed ride. The radi-
al-ply tires used on this vehicle are of
belted construction, and are selected
to complement the ride and handling
characteristics of your vehicle.Radial-ply tires have the same load
carrying capacity, as bias-ply or bias
belted tires of the same size, and use
the same recommended inflation
pressure. Mixing of radial-ply tires
with bias-ply or bias belted tires is
not recommended. Any combina-
tions of radial-ply and bias-ply or bias
belted tires when used on the same
vehicle will seriously deteriorate
vehicle handling. The best rule to fol-
low is: Identical pairs of radial-ply
tires should always be used as a set
for the front tires and a set for the
rear tires.
Longer wearing tires can be more
susceptible to irregular tread wear. It
is very important to follow the tire
rotation interval in this chapter to
achieve the tread life potential of
these tires. Cuts and punctures in
radial-ply tires are repairable only in
the tread area, because of sidewall
flexing. Consult your tire dealer for
radial-ply tire repairs.