tire LEXUS RX400H 2008 Repair Manual

Vehicle specifications6
429
RX400h_U
6-1. Specifications................. 430Maintenance data (fuel, oil level, etc.) .............. 430
Fuel information ..................... 442
Tire section names................. 445
6-2. Customization................ 458 Customizable features ........ 458
6-3. Initialization ................... 462 Items to initialize .................... 462

439
6-1. Specifications
6
Vehicle specifications
RX400h_U
Steering
Tires and wheelsType A
Free playLess than 1.2 in. (30 mm)
Ti r e s i z e225/65R17 101S
Tire inflation pressure
(Recommended cold tire inflation
pressure)
Driving under normal conditions Front:
32 psi (220 kPa, 2.2 kgf/cm
2 or bar)
Rear:
32 psi (220 kPa, 2.2 kgf/cm
2 or bar)
Spare:
32 psi (220 kPa, 2.2 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 1.5 psi (10 kPa, 0.1 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.
Wheel size17 × 6 1 /2 J
Wheel nut torque10.5 kgf•m (103 N•m, 76 ft•lbf)

440
6-1. Specifications
RX400h_UTy p e B
Ti r e s i z eP235/55R18 99V
Tire inflation pressure
(Recommended cold tire inflation
pressure)
Driving under normal conditions
Front:
30 psi (210 kPa, 2.1 kgf/cm
2 or bar)
Rear:
30 psi (210 kPa, 2.1 kgf/cm
2 or bar)
Spare:
30 psi (210 kPa, 2.1 kgf/cm
2 or bar)
Wheel size18 × 7 J
Wheel nut torque10.5 kgf•m (103 N•m, 76 ft•lbf)

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6-1. Specifications
6
Vehicle specifications
RX400h_U
Tire section names
Ty p i c a l t i r e s y m b o l s
Tire size(→ P. 4 4 7 )
DOT and Tire Identification Number (TIN) (→P. 4 4 6 )
Location of treadwear indicators (→ P. 3 3 1 )
Tire ply composition and materials
Plies are layers of rubber-coated parallel cords. Cords are the strands
which form the plies in a tire.
Radial tires or bias-ply tires
A radial tire has RADIAL on the sidewall. A tire not marked RADIAL is a
bias-ply tire.
TUBELESS or TUBE TYPE
A tubeless tire does not have a tube and air is directly filled in the tire. A
tube type tire has a tube inside the ti re and the tube maintains the air pres-
sure.
Load limit at maximum cold tire inflation pressure ( →P. 3 3 6 )
Maximum cold tire inflation pressure ( →P. 4 3 9 )
This means the pressure to which a tire may be inflated.
Uniform tire quality grading
For details, see “Uniform tire quality grading” that follows.

446
6-1. Specifications
RX400h_U
Typical DOT and tire iden tification number (TIN)
DOT symbol
*
Tire Identification Number (TIN)
Tire manufacturer's identifica-
tion mark
Tire size code
Manufacturer's optional tire
type code (3 or 4 letters)
Manufacturing week
Manufacturing year
*: The DOT symbol certifies thatthe tire conforms to applicable
Federal Motor Vehicle Safety
Standards.
Summer tire or all season tire (→ P. 3 3 6 )
An all season tire has “M+S” on the sidewall. A tire not marked “M+S” is a
summer tire.

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6-1. Specifications
6
Vehicle specifications
RX400h_U
Tire size■ Typical tire si ze 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 or 3 digits)
Speed symbol
(alphabet with one letter)

448
6-1. Specifications
RX400h_U■
Tire dimensions
Section width
Ti r e h e i g h t
Wheel diameter
Tire section names
Bead
Sidewall
Shoulder
Tr e a d
Belt
Inner liner
Reinforcing rubber
Carcass
Rim lines
Bead wires
Chafer

449
6-1. Specifications
6
Vehicle specifications
RX400h_U
Uniform tire quality gradingThis information has been prepared in accordance with regulations
issued by the National Highway Traffic Safety Administration of the
U.S.A. Department of Transportation.
It provides the purchasers and/or prospective purchasers of Lexus vehi-
cles 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 conform to Federal Safety Require-
ments 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 conditions on a specified gov-
ernment 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 sign ificantly from the norm due to varia-
tions in driving habits, service practices and differences in road characteris-
tics and climate.

450
6-1. Specifications
RX400h_U■
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.

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6-1. Specifications
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Vehicle specifications
RX400h_U
Glossary of tire terminology
Tire related termMeaning
Cold tire inflation pres-
sureTire 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
Recommended inflation
pressureCold tire inflation pressure recommended by a man-
ufacturer
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of automatic transmis-
sion, power steering, power brakes, power windows,
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 equip-
ment, 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 speci-
fied in the second column of Table 1
* that follows