
3914-6. Driving tips
4
Driving
RX450h_U_OM0E013U Accelerate the vehicle slowly, keep a safe distance between you and the vehicle
ahead, and drive at a reduced speed suitable to road conditions.
Park the vehicle and move the shift lever to P without setting the parking brake.
The parking brake may freeze up, preventing it from being released. If necessary,
block the wheels to prevent in advertent sliding or creeping.When the parking brake is in automatic mode, release the parking brake after shifting
the shift lever to P. ( P. 2 4 5 )
Use the correct tire chain size when mounting the tire chains. Chain size is regu-
lated for each tire size.
Side chain:
0.12 in. (3 mm) in diameter
0.43 in. (10.8 mm) in width
0.98 in. (25 mm) in length
Cross chain:
0.15 in. (3.9 mm) in diameter
0.54 in. (13.8 mm) in width
1.00 in. (25.3 mm) in length
Regulations regarding the use of tire chains vary depending on location and type
of road. Always check local regulations before installing chains.When driving the vehicle
When parking the vehicle
Selecting tire chains 1
2
3
4
5
6
Regulations on the use of tire chains

4996-3. Do-it-yourself maintenance
6
Maintenance and care
RX450h_U_OM0E013U When replacing wheels, care should be taken to ensure that they are equivalent
to those removed in load capacity , diameter, rim width and inset
* .
Replacement wheels are available at your Lexus dealer.
* : Conventionally referred to as “offset”.
Lexus does not recommend using the following: ●
Wheels of different sizes or types ●
Used wheels ●
Bent wheels that have been straightened ●
Use only Lexus wheel nuts and wrenches designed for use with your alumi-
num wheels. ●
When rotating, repairing or changing your tires, check that the wheel nuts are
still tight after driving 1000 miles (1600 km). ●
Be careful not to damage the aluminum wheels when using tire chains. ●
Use only Lexus genuine balance weights or equivalent and a plastic or rubber
hammer when balancing your wheels. ■
When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning valves and transmit-
ters that allow the tire pressure warning system to provide advance warning in the event
of a loss in tire inflation pressure. Whenever wheels are replaced, tire pressure warning
valves and transmitters must be installed. ( P. 4 8 8 )Wheels If a wheel is bent, cracked or heavily corroded, it should be replaced. Other-
wise, the tire may separate from the whee l or cause a loss of handling control.
Wheel selection
Aluminum wheel precautions

582
RX450h_U_OM0E013U 8-1. Spec ifications
* 1
: Unladen vehicle
* 2
: Vehicles with towing packageMaintenance data (fuel, oil level, etc.) Dimensions and weight Overall length 192.5 in. (4890 mm)
Overall width 74 . 6 i n . ( 1 8 9 5 m m )
Overall height
* 1
67.7 in. (1720 mm)
Wheelbase 109.8 in. (2790 mm)
Tr e a d Front 64.4 in. (1635 mm)
Rear 64.0 in. (1625 mm)
Vehicle capacity weight
(Occupants + luggage) 920 lb. (420 kg)
Trailer Weight Rating
* 2
(Trailer weight + cargo weight) 3500 lb. (1588 kg)

5978-1. Specifications
8
Vehicle specifications
RX450h_U_OM0E013U ■
Typical tire size information
The illustration indicates typical tire size.
Ti r e u s e
(P = Passenger car,
T = Temporary use)
Section width (millimeters)
Aspect ratio
(tire height to section width)
Tire construction code
(R = Radial, D = Diagonal)
Wheel diameter (inches)
Load index (2 digits or 3 digits)
Speed symbol (alphabet with one letter)■
Tire dimensions
Section width
Tire height
Wheel diameterTire size 1
2
3
4
5
6
7
1
2
3

5998-1. Specifications
8
Vehicle specifications
RX450h_U_OM0E013U 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 A■
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.
Performance may differ 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.Uniform Tire Quality Grading

602 8-1. Specifications
RX450h_U_OM0E013U 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

604 8-1. Specifications
RX450h_U_OM0E013U Intended outboard sidewall (a)The sidewall that contains a whitewall, bears white
lettering, or bears manu facturer, 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

6058-1. Specifications
8
Vehicle specifications
RX450h_U_OM0E013U 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