2020 LEXUS NX300 width

4218-1. Specifications
LEXUS NX300 Owners Manual_USA_M78389_en
8
Vehicle specifications
Chafer
This information has been prepared in
accordance with regulations issued by
the National Highway Traffic Safety
Administration of the U.S. Department
of Transportation.
It provides the purchasers and/or pro-
spective purchasers of Lexus vehicles
with information on uniform tire quality
grading.
Your Lexus dealer will help answer any
questions you may have as you read this
information.
■DOT quality grades
All passenger vehicle tires must con-
form to Federal Safety Requirements in
addition to these grades. Quality
grades can be found where applicable
on the tire sidewall between tread
shoulder and 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 condi-
tions on a specified government test
course.
For example, a tire graded 150 would wear
one and a half (1 - 1/2) times as well on the
government course as a tire graded 100.
The relative performa nce of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm due to variatio ns in driving habits,
service practices and differences 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 as measured under con-
trolled conditions on specified govern-
ment test surfaces of asphalt and
concrete.
A tire marked C may have poor traction
performance.
Warning: The traction grade assigned to
this tire is based on braking (straight
ahead) traction tests and does not include
cornering (turning) traction.
■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 sudd en tire failure.
Grade C corresponds to a level of perfor-
mance which all passenger car tires must
meet under the Fede ral Motor Vehicle
Safety Standard No. 109.
Grades B and A represent higher levels of
performance on the laboratory test wheel
than the minimum required by law.
Warning: The temperature grades for this
tire are established for a tire that is prop-
erly inflated and not overloaded.
Excessive speed, unde rinflation, or exces-
sive loading, either separately or in combi-
Uniform Tire Quality Grading
K

4228-1. Specifications
LEXUS NX300 Owners Manual_USA_M78389_en
nation, can cause heat buildup and
possible tire failure.
Glossary of tire terminology
Tire related
termMeaning
Cold tire infla-
tion 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 pres-
sureThe maximum cold inflated
pressure to which a tire
may be inflated, shown on
the sidewall of the tire
Recom-
mended infla-
tion pressureCold tire inflation pressure
recommended by a manu-
facturer
Accessory
weight
The combined weight (in
excess of thos e standard
items which may be
replaced) of transmission,
power steering, power
brakes, power windows,
power seats, radio and
heater, to the extent that
these items are available as
factory-installed equip-
ment (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 vehi-
cle weight
The sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight
(d) Production options
weight
Normal occu-
pant weight
150 lb. (68 kg) times the
number of occupants
specified in the second
column of Table 1
* that fol-
lows
Occupant
distribution
Distribution of occupants
in a vehicle as specified in
the third column of Table 1
*
below
Production
options
weight
The combined weight of
installed regu lar produc-
tion options weighing over
5 lb. (2.3 kg) in excess of
the standard items which
they replace, not previ-
ously considered in curb
weight or accessory
weight, including heavy
duty brakes, ride levelers,
roof rack, heavy duty bat-
tery, 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 diam-
eter)Nominal diameter of the
bead seat
Rim size des-
ignationRim diameter and width
Tire related termMeaning

4238-1. Specifications
LEXUS NX300 Owners Manual_USA_M78389_en
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Vehicle specifications
Rim type des-
ignationThe industry manufac-
turer’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 lug-
gage load plus 150 lb. (68
kg) times the vehicle’s des-
ignated seating capacity
Vehicle maxi-
mum load on
the tire
The load on an individual
tire that is determined by
distributing to each axle its
share of the maximum
loaded vehicle weight, and
dividing by two
Vehicle nor-
mal load on
the tire
The load on an individual
tire that is determined by
distributing to each axle its
share of curb weight,
accessory weight, and nor-
mal occupant weight (dis-
tributed in accordance
with Table 1
* below), and
dividing by two
Weather side
The 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
Bead separa-
tionA breakdown of the bond
between components in
the bead
Tire related termMeaning
Bias ply tire
A pneumatic tire in which
the ply cords that extend to
the beads are laid at alter-
nate angles substantially
less than 90 degrees to the
centerline of the tread
Carcass
The tire structure, except
tread and sidewall rubber
which, when inflated, bears
the load
Chunking
The breaking away of
pieces of the tread or side-
wall
CordThe strands forming the
plies in the tire
Cord separa-
tionThe parting of cords from
adjacent rubber com-
pounds
Cracking
Any 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 corresponding
standard tire
Tire related termMeaning

4248-1. Specifications
LEXUS NX300 Owners Manual_USA_M78389_en
GrooveThe space between two
adjacent tread ribs
Innerliner
The layer(s) forming the
inside surface of a tubeless
tire that contains the inflat-
ing medium within the tire
Innerliner
separationThe parting of the inner-
liner from cord material in
the carcass
Intended out-
board side-
wall
(a)The sidewall that con-
tains a whitewall, bears
white lettering, or bears
manufacturer, brand,
and/or model name mold-
ing that is higher or deeper
than the same molding on
the other sidewall of the
tire, or
(b)The outward facing
sidewall of an asymmetri-
cal 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 primarily
intended for use on light-
weight trucks or multipur-
pose passenger vehicles
Load rating
The maximum load that a
tire is rated to carry for a
given inflation pressure
Maximum
load rating
The load rating for a tire at
the maximum permissible
inflation pressure for that
tire
Tire related
termMeaning
Maximum
permissible
inflation pres-
sureThe maximum cold infla-
tion pressure to which a
tire may be inflated
Measuring
rimThe rim on which a tire is
fitted for physical dimen-
sion requirements
Open splice
Any parting at any junction
of tread, sidewall, or inner-
liner that extends to cord
material
Outer diame-
terThe overall diameter of an
inflated new tire
Overall width
The linear distance
between the exteriors of
the sidewalls of an inflated
tire, including elevations
due to labeling, decora-
tions, or protective bands
or ribs
Passenger car
tire
A tire intended for use on
passenger cars, multipur-
pose 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 separation
A parting of rubber com-
pound between adjacent
plies
Tire related termMeaning

4258-1. Specifications
LEXUS NX300 Owners Manual_USA_M78389_en
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Vehicle specifications
*:Table 1  Occupant loading and distri-
bution for vehicle normal load for vari-
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
Radial ply tire
A pneumatic tire in which
the ply cords that extend to
the beads are laid at sub-
stantially 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 corresponding
standard tire
Section width
The linear distance
between the exteriors of
the sidewalls of an inflated
tire, excluding elevations
due to labeling, decora-
tion, or protective bands
Sidewall
That portion of a tire
between the tread and
bead
Sidewall sep-
arationThe parting of the rubber
compound from the cord
material in the sidewall
Tire related termMeaning
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
Test rim
The rim on which a tire is
fitted for testing, and may
be any rim listed as appro-
priate for use with that tire
Tread
That portion of a tire that
comes into contact with
the road
Tread rib
A tread section running
circumferentially around a
tire
Tread separa-
tionPulling away of the tread
from the tire carcass
Treadwear
indicators
(TWI)
The projections within the
principal grooves designed
to give a visual indication of
the degrees of wear of the
tread
Wheel-hold-
ing fixtureThe fixture used to hold the
wheel and tire assembly
securely during testing
Tire related termMeaning