2010 Lexus GS450h wheel

596
6-1. Specifications
GS_HV_U (OM30C81U)
February 1, 2010 11:10 am
Steering
Tires and wheels
Free playLess than 1.2 in. (30 mm)
Ti r e s i z e
245/40R18 93Y, 245/40RF18 93Y, 
P245/40R18 93V, P245/40RF18 93V,
245/40ZR18, T155/70D17 110M (spare)
Tire inflation pressure
(Recommended cold tire inflation
pressure)
Driving under normal conditions
Front: 35 psi (240 kPa, 2.4 kgf/cm2 or bar)
Rear: 35 psi (240 kPa, 2.4 kgf/cm2 or bar)
Driving at high speeds above 100 mph (160
km/h) (in countries where such speeds are per-
mitted by law)
Add 9 psi (60 kPa, 0.6 kgf/cm
2 or bar) to the
front tires and rear tires. Never exceed the
maximum cold tire inflation pressure indicated
on the tire sidewall.
Spare tire inflation pressure
(Recommended cold tire inflation
pressure)
60 psi (420 kPa, 4.2 kgf/cm2 or bar)
Wheel size18  8J, 17  4T (spare)
Wheel nut torque76 ft•lbf (103 N•m, 10.5 kgf•m)

604
6-1. Specifications
GS_HV_U (OM30C81U)
February 1, 2010 11:10 am
Tire size
■Typical tire size information
Ty p e A
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 or 3 digits)
Speed symbol
(alphabet with one letter)
Speed category
(alphabet with one letter)
Run-flat tire code
Ty p e B
Ty p e C

605
6-1. Specifications
6
Vehicle specifications
GS_HV_U (OM30C81U)
February 1, 2010 11:10 am
■Tire dimensions
Section width
Ti r e h e i g h t
Wheel diameter
Tire section names
Bead
Sidewall
Shoulder
Tread
Belt
Inner liner
Reinforcing rubber
Carcass
Rim lines
Bead wires
Chafer

607
6-1. Specifications
6
Vehicle specifications
GS_HV_U (OM30C81U)
February 1, 2010 11:10 am
■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 controlled conditions on specified government 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) trac-
tion.
■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 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 fail-
ure.
The grade C corresponds 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 laboratory
test wheel than the minimum required by law.
Warning: The temperature grades for this tire are established for a tire that
is properly inflated and not overloaded.
Excessive speed, underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.

609
6-1. Specifications
6
Vehicle specifications
GS_HV_U (OM30C81U)
February 1, 2010 11:10 am
Tire related termMeaning
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
considered in curb weight or accessory weight,
including heavy duty brakes, ride levelers, roof rack,
heavy duty battery, and special trim
RimA 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 luggage load plus 150 lb.
(68 kg) times the vehicle’s designated seating capac-
ity
Vehicle maximum load on
the tireThe 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 normal 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 normal occupant weight (dis-
tributed in accordance with Table 1
* below), and
dividing by two
We a t h e r s i d eThe surface area of the rim not covered by the
inflated tire

612
6-1. Specifications
GS_HV_U (OM30C81U)
February 1, 2010 11:10 am
Tire related termMeaning
Overall width
The linear distance between the exteriors of the side-
walls of an inflated tire, including elevations due to
labeling, decorations, 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 separationA parting of rubber compound between adjacent
plies
Pneumatic tire
A mechanical device made of rubber, chemicals, fab-
ric 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
SidewallThat portion of a tire between the tread and bead
Sidewall separationThe parting of the rubber compound from the cord
material in the sidewall

613
6-1. Specifications
6
Vehicle specifications
GS_HV_U (OM30C81U)
February 1, 2010 11:10 am
*: Table 1  Occupant loading and distribution for vehicle normal load for
various designated seating capacities
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
Te s t r i mThe 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 dThat portion of a tire that comes into contact with the
road
Tr e a d r i bA tread section running circumferentially around a
tire
Tr e a d s e p a r a t i o nPulling 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 fixtureThe fixture used to hold the wheel and tire assembly
securely during testing

636
Alphabetical index
GS_HV_U (OM30C81U)
February 1, 2010 11:29 am
Safety Connect ......................................433
Seat belts
Adjusting the seat belt........................ 75
Automatic locking retractor............ 78
Child restraint system 
installation ............................................128
Cleaning and maintaining 
the seat belts ..................................... 446
Emergency locking retractor ......... 78
How to wear your seat belt............. 75
How your child should wear 
the seat belt .......................................... 78
Pre-collision seat belts ........................ 77
Pregnant women, 
proper seat belt use......................... 78
Reminder light .....................................536
Seat belt extenders .............................. 79
Seat belt pretensioners ....................... 77
Seat heaters/ventilators...................... 414
Seating capacity ..................................... 413
Seats
Adjustment............................................... 65
Adjustment precautions .................... 66
Child seats/child restraint 
system installation ............................128
Cleaning................................................. 445
Driver’s seat position memory....... 67
Head restraint.......................................... 72
Properly sitting in the seat .............. 105
Seat heaters ............................................ 413
Service reminder indicators ............. 165Shift lever
If the shift lever cannot be 
shifted from “P” ................................573
Transmission.......................................... 154
Shift lock system.................................... 573
Shopping bag hooks ............................. 421
Side airbags ..............................................107
Side marker lights
Switch .......................................................... 171
Side mirror
Adjusting and folding ......................... 85
Mirror position memory .................... 67
Smart access system with 
push-button start
Antenna location ................................... 43
Entry function ............................................41
Starting the 
hybrid system.....................................150
Spare tire
Inflation pressure ............................... 596
Storage location .................................. 561
Spark plug ............................................... 593
Specifications .........................................588
Speedometer ............................................ 161
Steering wheel
Adjustment ...............................................82
Audio switches ....................................342
Steering wheel position 
memory .................................................. 67
Storage compartment ........................ 403
Storage feature ..................................... 398
Stuck
If your vehicle becomes stuck .... 584
Sun visors ................................................. 406S