2004 Lexus GX470 Audio System / LEXUS 2004 GX470 FROM AUG. 2004 THROUGH SEP. 2004 PROD. OWNER'S MANUAL (OM60B55U)

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Incorrect tire inflation pressure may waste fuel, reduce
the comfort of driving, reduce tire life and make your
vehicle less safe to drive.
If a tire frequently needs refilling, have it checked by
your Lexus dealer.
CAUTION
Keep your tires properly inflated. Otherwise, the
following conditions may occur and cause an
accident resulting in death or serious injuries.
Low tire pressure (underinflation) Ð
Excessive wear
 Uneven wear
 Poor handling
 Possibility of blowouts from an overheated
tire
 Poor sealing of the tire bead
 Wheel deformation and/or tire separation
 A greater possibility of tire damage from road
hazards
High tire pressure (overinflation) Ð
Poor handling
 Excessive wear
 Uneven wear
 A greater possibility of tire damage from road
hazards

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583
TIRE INFORMATION
Tire symbols
63PY018

The illustration indicates typical tire symbols.

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584
1Tire size: For details, see Tire sizeº on page
585.
2DOT and Tire Identification Number (TIN): For
details, see DOT and Tire Identification Number
(TIN)º on page 585.
3Location of the tread wear indicators: For
details, see Checking and replacing tiresº on
page 594.
4Tire ply composition and materials: Plies mean
a layer of rubber-coated parallel cords. Cords
mean the strands forming the plies in the tire.
5Radial tires or bias-ply tires: A radial tire has
RADIALº on the sidewall. A tire not marked with
RADIALº is a bias-ply tire.
6TUBELESSº or TUBE TYPEº: A tubeless tire
does not have a tube inside the tire. A tube type
tire has a tube inside the tire and the tube
maintains the air pressure.
7Load limit at maximum cold tire inflation
pressure: For details, see Checking and
replacing tiresº on page 594.
8Maximum cold tire inflation pressure: This
means the pressure to which a tire may be
inflated. For details about recommended cold tire
inflation pressure, see Specificationsº on page
572.
9Uniform tire quality grading: For details, see
Uniform tire quality gradingº that follows.
10Summer tire or all season tire: An all season
tire has M+Sº on the sidewall. The tire not
marked with M+Sº is a summer tire. For details,
see Types of tiresº on page 592.

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585
DOT and Tire Identification Number (TIN)

The illustration indicates typical DOT and TireIdentification Number (TIN).
1DOTº symbol
2Tire Identification Number (TIN)
3Tire manufacturer's identification mark
4Tire size code
5Manufacturer's optional tire type code
6Manufacturing week
7Manufacturing year
The DOTº symbol certifies that the tire conforms to
applicable Federal Motor Vehicle Safety Standards.
Tire size

The illustration indicates typical tire size.
1Tire use (P=Passenger car, T=Temporaryuse)
2Section width (in millimeters)
3Aspect ratio (tire height to section width)
4Tire construction code (R=Radial, D=Diagonal)
5Wheel diameter (in inches)
6Load index (2 digits or 3 digits)
7Speed symbol (alphabet with one letter)

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586

1Section width
2Tire height
3Wheel diameter
Name of each section of tire

1Bead
2Sidewall
3Shoulder
4Tread
5Belt
6Inner liner
7Reinforcing rubber
8Carcass
9Rim lines
10Bead wires
11Chafer

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587
Uniform tire quality grading
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 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 information.
DOT quality grades Ð All passenger car tires must
conform 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 ATreadwear
Ð The treadwear grade is a comparative
rating 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 Ð 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.
Traction AA, A, B, C Ð 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) traction.

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588
Temperature A, B, C Ð 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 failure. 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 grade for this tire
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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589
Glossary of tire terminology
Tire related termMeaning
Accessory weightthe combined weight (in excess of those standard items which may be rep\
laced)
of automatic transmission, 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)
Cold tire inflation
pressuretire inflation pressure when the vehicle has been parked for at least 3 \
hours or
more, or it has not been driven more than 1.5 km or 1 mile under that co\
ndition
Curb weightthe weight of a motor vehicle with standard equipment including the maxi\
mum
capacity of fuel, oil, and coolant, and, if so equipped, air conditionin\
g and
additional weight optional engine
Intended outboard
sidewall(a) the sidewall that contains a whitewall, bears white lettering or bearsmanufacturer, 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 particula\
r side that must always face outward when mounted on a vehicle
Maximum inflation
pressurethe maximum cold inflation pressure to which a tire may be inflated and \
it is
shown on the sidewall of the tire
Maximum loaded
vehicle weightthe sum of Ð
(a) curb weight;
(b) accessory weight;
(c) vehicle capacity weight; and
(d) production options weight
Normal occupant
weight68 kg (150 lb.) times the number of occupants specified in the second \
column of
Table 1 that follows