2015 LEXUS NX300h Owners Manual

6259-1. Specifications
9
Vehicle specifications
NX300h_U_OM78007U Bead
Sidewall
Shoulder
Tr e a d
Belt
Inner liner
Reinforcing rubber
Carcass
Rim lines
Bead wires
Chafer
This information has been prepared in acco rdance with regulations issued by the
National Highway Traffic Safety Administration of the U.S. Department of Trans-
portation.
It provides the purchasers and/or prospective 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 infor-
mation.■
DOT quality grades
All passenger vehicle tires must conform to Federal Safety Requirements in
addition to these grades. Quality grad es can be found where applicable on
the tire sidewall between tread shoulder and maximum section width. For example: Treadwear 200 Traction AA Temperature ATire section names 1
2
3
4
5
6
7
8
9
10
11
Uniform Tire Quality Grading

626 9-1. Specifications
NX300h_U_OM78007U ■
Tr e a d w e a r
The treadwear grade is a comparative rati ng based on the wear rate of the tire
when tested under controlled conditions 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 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.■
Tr a c t i o n A A , A , B , C
The traction grades, from highest to lowest, are AA, A, B and C, and they rep-
resent the tire’s ability to stop on we t pavement as measured under controlled
conditions on specified government te st surfaces of asphalt and concrete.A tire marked C may have poor traction performance.
Warning: The traction grade assigned to th is 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 highes t), B, and C, representing the tire’s
resistance to the generation of heat and its ability to dissipate heat when
tested under controlled conditions 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 corresponds to a level of perfor mance 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 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, underinflation, or excessiv e loading, either separately or in com-
bination, can cause heat buildup and possible tire failure.

6279-1. Specifications
9
Vehicle specifications
NX300h_U_OM78007U Glossary of tire terminology Tire related term Meaning
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 un der that condition
Maximum inflation pres-
sure The maximum cold inflated pressure to which a tire may
be inflated, shown on the sidewall of the tire
Recommended inflation
pressure Cold tire inflation pressure recommended by a manu-
facturer
Accessory weight The combined weight (in excess of those standard items
which may be replaced) of transmission, power steer-
ing, power brakes, power wi ndows, power seats, radio
and heater, to the extent that these items are available 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 co nditioning 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 weight 150 lb. (68 kg) times the numb er of occupa nts specified
in the second column of Table 1
* that follows
Occupant distribution Distribution of occupants in a vehicle as specified in the
third column of Table 1
* below

628 9-1. Specifications
NX300h_U_OM78007U Production 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 con-
sidered 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 designation Rim diameter and width
Rim type designation The industry manufacturer’s designation for a rim by
style or code
Rim width Nominal distance between rim flanges
Vehicle capacity weight
(Total load capacity) The rated cargo and luggage 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 determined by dis-
tributing 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 determined by dis-
tributing to each axle its sh are of curb weight, accessory
weight, and normal occupant weight (distributed in
accordance with Table 1
* below), and dividing by two
We a t h e r s i d e 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
rimTire related term Meaning

6299-1. Specifications
9
Vehicle specifications
NX300h_U_OM78007U Bead separation A breakdown of the bond be tween components in the
bead
Bias ply tire A pneumatic tire in which the ply cords that extend to
the beads are laid at altern ate 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 sidewall
Cord The strands forming th e plies in the tire
Cord separation The parting of cords from adjacent rubber compounds
Cracking Any parting within the tread, sidewall, or innerliner 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
Groove The 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 separation The parting of the i nnerliner from cord material in the
carcassTire related term Meaning

630 9-1. Specifications
NX300h_U_OM78007U Intended outboard sidewall (a) The sidewall that contains a whitewall, bears white
lettering, or bears manufacturer, 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 asymmetrical tire
that has a particular side that must always face out-
ward when mounted on a vehicle
Light truck (LT) tire A tire designated by its manufacturer as primarily
intended for use on lightweight trucks or multipurpose
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
Maximum permissible infla-
tion pressure The maximum cold inflation pressure to which a tire may
be inflated
Measuring rim The rim on which a tire is fitted for physical dimension
requirements
Open splice Any parting at any junction of tread, sidewall, or inner-
liner that extends to cord material
Outer diameter The overall diameter of an inflated new tire
Overall width The linear distance between the exteriors of the side-
walls of an inflated tire, incl uding elevations due to label-
ing, decorations, or pr otective 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.
Ply A layer of rubber-coated parallel cords
Ply separation A parting of rubber compou nd between adjacent pliesTire related term Meaning

6319-1. Specifications
9
Vehicle specifications
NX300h_U_OM78007U Pneumatic tire A mechanical device made of rubber, chemicals, fabric
and steel or other materials, that, when mounted on an
automotive wheel, provides 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 corresponding standard tire
Section width The linear distance between the exteriors of the side-
walls of an inflated tire, excluding elevations due to
labeling, decoration, or protective bands
Sidewall That portion of a tire between the tread and bead
Sidewall separation The 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 Ref-
erence Test Tire, when using the snow traction test as
described in ASTM F-1805-00, Standard Test Method
for Single Wheel Driving Tract ion 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
Tr e a d That portion of a tire that comes into contact with the
road
Tr e a d r i b A tread section running circumferentially around a tireTire related term Meaning

632 9-1. Specifications
NX300h_U_OM78007U * :Table 1  Occupant loading and distribution fo r vehicle normal load for various des-
ignated seating capacitiesTread separation Pulling 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-holding fixture The fixture used to hold the wheel and tire assembly
securely during testingTire related term Meaning
Designated seating capac-
ity, Number of occupants Vehicle normal load, Num-
ber of occupants Occupant distribution in a
normally loaded vehicle
2 through 4 2 2 in front
5 through 10 3 2 in front, 1 in second seat
11 through 15 5 2 in front, 1 in second seat, 1
in third seat, 1 in fourth seat
16 through 20 7 2 in front, 2 in second seat,
2 in third seat, 1 in fourth
seat