2018 Hyundai Ioniq Electric Owner's Manual

7-32
Maintenance
1. Manufacturer or brand name
Manufacturer or brand name is
shown.
2. Tire size designation
A tire’s sidewall is marked with a tire
size designation. You will need this
information when selecting replace-
ment tires for your car. The following
explains what the letters and num-
bers in the tire size designation
mean.Example tire size designation:
(These numbers are provided as an
example only; your tire size designa-
tor could vary depending on your
vehicle.)
205/55R16 91H
205 - Tire width in millimeters.
55 - Aspect ratio. The tire’s section
height as a percentage of its
width.
R - Tire construction code (Radial).
16 - Rim diameter in inches.
91 - Load Index, a numerical code associated with the maximum
load the tire can carry.
H - Speed Rating Symbol. See the speed rating chart in this section
for additional information.
Wheel size designation
Wheels are also marked with impor-
tant information that you need if you
ever have to replace one. The follow-
ing explains what the letters and
numbers in the wheel size designa-
tion mean.
Example wheel size designation:
6.5J X 16
6.5 - Rim width in inches.
J - Rim contour designation.
16 - Rim diameter in inches.
OLMB073028
1
1
2
34
5,6
7

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7
Maintenance
Tire speed ratings
The chart below lists many of the dif-
ferent speed ratings currently being
used for passenger car tires. The
speed rating is part of the tire size
designation on the sidewall of the
tire. This symbol corresponds to that
tire’s designed maximum safe oper-
ating speed.
3. Checking tire life (TIN : TireIdentification Number)
Any tires that are over six years old,
based on the manufacturing date,
(including the spare tire) should be
replaced by new ones. You can find
the manufacturing date on the tire
sidewall (possibly on the inside of the
wheel), displaying the DOT Code.
The DOT Code is a series of num-
bers on a tire consisting of numbers
and English letters. The manufactur-
ing date is designated by the last four
digits (characters) of the DOT code.
DOT : XXXX XXXX OOOO
The front part of the DOT means a
plant code number, tire size and
tread pattern and the last four num-
bers indicate week and year manu-
factured.
For example:
DOT XXXX XXXX 1418 represents
that the tire was produced in the 14th
week of 2018.
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.
Speed
Rating
Symbol Maximum Speed
S 112 mph (180 km/h) T 118 mph (190 km/h)
H 130 mph (210 km/h) V 149 mph (240 km/h)
W 168 mph (270 km/h)
Y186 mph (300 km/h)

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Maintenance
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:
TREAD wear 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.
Traction - AA, A, B & C
The traction grades, from highest to
lowest, are AA, A, B and C. Those
grades represent the tire's ability to
stop on wet pavement as measured
under controlled conditions on spec-
ified government test surfaces of
asphalt and concrete. A tire marked
C may have poor traction perform-
ance.The traction grade assigned to
this tire is based on straight-
ahead braking traction tests,
and does not include accelera-
tion, cornering, hydroplaning,
or peak traction characteristics.
WARNING

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7
Maintenance
Temperature - A, B & C
The temperature grades are A (the
highest), B and C representing the
tire’s resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled condi-
tions on a specified indoor laboratory
test wheel.
Sustained high temperature can
cause the material of the tire to
degenerate and reduce tire life, and
excessive temperature can lead to
sudden tire failure. Grade C
responds to a level of performance
which all passenger car tires must
meet under the Federal Motor
Vehicle Safety Standard No. 109.
Grades B and A represent higher
levels of performance on the labora-
tory test wheel than the minimum
required by law.
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.
The temperature grade for this
tire is established for a tire that
is properly inflated and not
overloaded. Excessive speed,
under-inflation, over-inflation,
or excessive loading, either
separately or in combination,
can cause heat build-up and
possible sudden tire failure.
This may cause loss of vehicle
control resulting in an accident.
WARNING

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Maintenance
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.
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.

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7
Maintenance
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.
Recommended InflationPressure
Vehicle manufacturer's recommend-
ed tire inflation pressure as shown
on the tire placard.

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Maintenance
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.

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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.