2021 TOYOTA PRIUS Owners Manual (in English)

PRIUS_OM_OM47E09U_(U)
6818-1. Specifications
8
Vehicle specifications
■Tire dimensionsSection width
Tire height
Wheel diameter
Bead
Sidewall
Shoulder
Tread
Belt
Inner liner
Reinforcing rubber
Carcass
Rim lines
Bead wires
Chafer
1
2
3
Tire section names
1
2
3
4
5
6
7
8
9
10
11

682
PRIUS_OM_OM47E09U_(U)
8-1. Specifications
This information has been prepared in accordance with regulations
issued by the National Highway Tr affic Safety Administration of the
U.S. Department of Transportation.
It provides the purchasers and/or prospective purchasers of Toyota
vehicles with info rmation on uniform ti re quality grading.
Your Toyota dealer will help answer any questions you may have as
you read this information.
■DOT quality grades
All passenger vehicle tires must conform to Federal Safety Requ ire-
ments in addition to these grades. Quality grades can be found
where applicable on the tire sidewall between tread shoulder an d
maximum section width.
For example: Treadwear 200 Traction AA Temperature A
■Treadwear
The treadwear grade is a comparative rating based on the wear
rate of the tire when tested under controlled conditions on a s peci-
fied government t est course.
For example, a tire graded 150 would wear one and a half (1 - 1 /2)
times as well on the governmen t course as a tire graded 100.
The relative performance of tires depends upon the actual condi -
tions of their use. Performance ma y differ significantly from the norm
due to variations in driving habits, service practices and diff erences
in road characteristics and climate.
■Traction AA, A, B, C
The traction grades, from highest to lowest, are AA, A, B and C ,
and they represent the tire’s ability to stop on wet pavement a s
measured under controlled conditions on specified government te st
surfaces of asphalt and concrete.
A tire marked C may have p oor traction performance.
Warning: The traction grade assigned to this tire is based on b raking
(straight ahead) traction tests and does not include cornering (turn-
ing) traction.
Uniform Tire Quality Grading

PRIUS_OM_OM47E09U_(U)
6838-1. Specifications
8
Vehicle specifications
■Temperature A, B, C
The temperature grades are A (the highest), B, and C, representing
the tire’s resistance to the ge neration of heat and its ability to dissi-
pate heat when tested under contr olled conditions on a specified
indoor laboratory test wheel.
Sustained high temperature can c ause the material of the tire to
degenerate and reduce tire life, and excessive temperature can lead
to sudden tire failure.
Grade C corresponds to a level of performance which all passeng er
car tires must meet under the Fe deral Motor Vehicle Safety Stan-
dard No. 109.
Grades B and A represent higher levels of performance on the labo-
ratory test wheel than the minimum required by law.
Warning: The temperature grades of a tire assume that it is pro perly
inflated and not overloaded.
Excessive speed, underinflation, or excessive loading, either sepa-
rately or in combination, can c ause heat buildup and possible t ire
failure.

684
PRIUS_OM_OM47E09U_(U)
8-1. Specifications
Glossary of tire terminology
Tire related termMeaning
Cold tire inflation
pressure
Tire pressure when the vehicle has been
parked for three hours or more, or has not
been driven more than 1 mile or 1.5 km under
that condition
Maximum inflation
pressureThe maximum cold inflated pressure to which
a tire may be inflated, shown on the sidewall
of the tire
Recommended
inflation pressureCold tire inflation pressure recommended by a
manufacturer
Accessory weight
The combined weight (in excess of those stan-
dard items which may be replaced) of hybrid
transmission, power steering, power brakes,
power windows, power seats, radio and
heater, to the extent that these items are avail-
able as factory-installed equipment (whether
installed or not)
Curb weight
The weight of a motor vehicle with standard
equipment, including the maximum capacity of
fuel, oil and coolant, and if so equipped, air
conditioning and additional weight optional
engine
Maximum loaded
vehicle weight
The sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight
(d) Production options weight
Normal occupant
weight150 lb. (68 kg) times the number of occupants
specified in the second column of Table 1
*
that follows
Occupant distributionDistribution of occupants in a vehicle as speci-
fied in the third column of Table 1
* below

PRIUS_OM_OM47E09U_(U)
6858-1. Specifications
8
Vehicle specifications
Production options
weight
The combined weight of installed regular pro-
duction 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, including heavy
duty brakes, ride levelers, roof rack, heavy
duty 12-volt battery, and special trim
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated
Rim diameter
(Wheel diameter)Nominal diameter of the bead seat
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 l uggage load plus 150 lb.
(68 kg) times the vehicle’s designated seating
capacity
Vehicle maximum load
on the tire
The load on an individual tire that is deter-
mined by distributing 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 deter-
mined by distributing 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
Bead
The part of the tire that is made of steel wires,
wrapped or reinforced by ply cords and that is
shaped to fit the rim
Tire related termMeaning

686
PRIUS_OM_OM47E09U_(U)
8-1. Specifications
Bead separationA breakdown of the bond between compo-
nents 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, sidewall, or inner-
liner 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
with 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 tire
A tire designed to operate at higher loads and
at higher inflation pressures than the corre-
sponding standard tire
GrooveThe space between two adjacent tread ribs
Innerliner
The layer(s) forming the inside surface of a
tubeless tire that contains the inflating medium
within the tire
Innerliner separationThe parting of the innerliner from cord material
in the carcass
Tire related termMeaning

PRIUS_OM_OM47E09U_(U)
6878-1. Specifications
8
Vehicle specifications
Intended outboard
sidewall
(a) The sidewall that contains a whitewall,bears white lettering, or bears manufac-
turer, brand, and/or model name molding
that is higher or deeper than the same
molding on the other sidewall of the tire, or
(b) The outward facing sidewall of an asym-
metrical tire that has a particular side that
must always face outward when mounted
on a vehicle
Light truck (LT) tire
A tire designated by its manufacturer as pri-
marily intended for use on lightweight trucks
or multipurpose passenger vehicles
Load ratingThe maximum load that a tire is rated to carry
for a given inflation pressure
Maximum load ratingThe load rating for a tire at the maximum per-
missible inflation pressure for that tire
Maximum permissible
inflation pressureThe maximum cold inflation pressure to which
a tire may be inflated
Measuring rimThe rim on which a tire is fitted for physical
dimension requirements
Open spliceAny parting at any junction of tread, sidewall,
or innerliner that extends to cord material
Outer diameterThe overall diameter of an inflated new tire
Overall width
The linear distance between the exteriors of
the sidewalls of an inflated tire, including ele-
vations due to labeling, decorations, or protec-
tive bands or ribs
Passenger car tire
A tire intended for use on passenger cars,
multipurpose passenger vehicles, and trucks,
that have a gross vehicle weight rating
(GVWR) of 10,000 lb. or less.
PlyA layer of rubber-coated parallel cords
Ply separationA parting of rubber compound between adja-
cent plies
Tire related termMeaning

688
PRIUS_OM_OM47E09U_(U)
8-1. Specifications
Pneumatic tire
A mechanical device made of rubber, chemi-
cals, fabric and steel or other materials, that,
when mounted on an automotive wheel, pro-
vides the traction and contains the gas or fluid
that sustains the load
Radial ply tire
A pneumatic tire in which the ply cords that
extend to the beads are laid at substantially 90
degrees to the centerline of the tread
Reinforced tire
A tire designed to operate at higher loads and
at higher inflation pressures than the corre-
sponding standard tire
Section width
The linear distance between the exteriors of
the sidewalls of an inflated tire, excluding ele-
vations due to labeling, decoration, or protec-
tive bands
SidewallThat portion of a tire between the tread and
bead
Sidewall separationThe parting of the rubber compound from the
cord material in the sidewall
Snow tire
A tire that attains a traction index equal to or
greater than 110, compared to the ASTM E-
1136 Standard Reference Test Tire, when
using the snow traction test as described in
ASTM F-1805-00, Standard Test Method for
Single Wheel Driving Traction in a Straight
Line on Snow-and Ice-Covered Surfaces, and
which is marked with an Alpine Symbol ( )
on at least one sidewall
Te s t r i m
The rim on which a tire is fitted for testing, and
may be any rim listed as appropriate for use
with that tire
TreadThat portion of a tire that comes into contact
with the road
Tread ribA tread section running circumferentially
around a tire
Tire related termMeaning