2006 Lexus GS430 Scheduled Maintenance Guide / LEXUS 2006 GS430/GS300 FROM JAN. 2005 PROD. OWNER'S MANUAL (OM30649U)

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540
The recommended cold tire inflation pressure, tire
size and the combined weight of occupants and
cargo (vehicle capacity weight) are described on the
tire and loading information label.
You should check the tire inflation pressure every two
weeks, or at least once a month. And do not forget the
spare! The inflation pressure for the spare tire should be
420 kPa (4.3 kgf/cm
2, 4.2 bar, 60 psi).
The following instructions for checking tire inflation
pressure should be observed:
 The pressure should be checked only when the
tires are cold. If your vehicle has been parked for at
least 3 hours and has not been driven for more than
1.5 km or 1 mile since, you will get an accurate cold
tire inflation pressure reading.
 Always use a tire pressure gauge. The appearance
of the tire can be misleading. Besides, tire inflation
pressures that are even just a few pounds off can
degrade ride and handling.
 Do not bleed or reduce tire inflation pressure after
driving. It is normal for the tire inflation pressure to
be higher after driving.
 Never exceed the vehicle capacity weight.
Passengers and luggage weight should be located so
that the vehicle is balanced. Inspection and adjustment procedureG63001
 1Tire valve
2Tire pressure gauge
1. Remove the tire valve cap.
2. Press the tip of the tire pressure gauge to the tire
valve.
3. Read the pressure using the graduations of the
gauge.
4. In case the tire inflation pressure is not within the
prescribed range, insert the compressed air from the
valve. In case of applying too much air, press the center
of the valve and release the air to adjust.
5. After completing the tire inflation pressure
measurement and adjustment, apply soapy water to the
valve and check for leakage.

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6. Install the tire valve cap.
If a gauge and air pump are not available, have your
vehicle checked by your Lexus dealer.
CAUTION
Be sure to reinstall the tire valve caps. Without the
valve caps, dirt or moisture could get into the
valve core and cause air leakage. If the caps have
been lost, have new ones put on as soon as
possible.
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 needs frequent 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):
 Excessive wear
 Uneven wear
 Poor handling
 Possibility of bl owouts 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):
 Poor handling
 Excessive wear
 Uneven wear
 A greater possibility of tire damage from road
hazards

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542
TIRE INFORMATION
Tire symbols (Standard and runflat tire)
G63006
The illustration indicates typical tire symbols.

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543
1 Tire size: For details, see “Tire size” on page
546.
2 DOT and Tire Identification Number (TIN): For
details, see “DOT and Tire Identification Number
(TIN)” on page 546.
3 Tire ply composition and materials : Plies
mean a layer of rubber −coated parallel cords.
Cords mean the strands forming the plies in the
tire.
4 Load limit at maximum cold tire inflation
pressure: For details, see “Checking and
replacing tires” on page 554.
5 Uniform tire quality grading For details, see
“Uniform tire quality grading” on page 548.
6 Maximum cold tire inflation pressure: This
means the pressure to which a tire may be
inflated. For recommended cold tire inflation
pressure, see “Specifications” on page 537.
7 “TUBELESS” or “TUBE TYPE”: A tubeless tire
does not have a tube inside the tire and air is
directly filled in the tire. A tube type tire has a
tube inside the tire and the tube maintains the air
pressure.
8 Radial tires or biasply tires : A radial tire has
“RADIAL” on the sidewall. A tire not marked with
“RADIAL” is a bias −ply tire.
9 Runflat tire (RFT) or standard tire: This
vehicle can be equipped with either run −flat tires
(RFT) or standard tires. A “RFT” or “DSST” mark
is molded on the sidewall of the run −flat tire. For
details, see “Run −flat tires” on page 552.
10 Location of tread wear indicators: For details,
see “Checking and replacing tires” on page 554.
11 Summer tire or all season tire: An all season
tire has “M+S” on the sidewall. The tire not
marked with “M+S” is a summer tire. For details,
see “Types of tires” on page 553.

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544
Tire symbols (Compact spare tire)
G63007
The illustration indicates typical tire symbols.

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545
1 “TEMPORARY USE ONLY”: A compact spare
tire is identified by the phrase “TEMPOTRARY
USE ONLY” molded into its sidewall. This tire is
designed for temporary emergency use only. For
details, see “Compact spare tire” on page 471.
2 Tire size: For details, see “Tire size” on page
546.
3 DOT and Tire Identification Number (TIN): For
details, see “DOT and Tire Identification Number
(TIN)” on page 546.
4 Load limit at maximum cold tire inflation
pressure: For details, see “Checking and
replacing tires” on page 554.
5 Maximum cold tire inflation pressure: This
means the pressure to which a tire may be
inflated. For recommended cold tire inflation
pressure, see “Specifications” on page 532.
6 Tire ply composition and materials : Plies
mean a layer of rubber −coated parallel cords.
Cords mean the strands forming the plies in the
tire.
7 Location of tread wear indicators: For details,
see “Checking and replacing tires” on page 554.
8 “TUBELESS” or “TUBE TYPE”: A tubeless tire
does not have a tube inside the tire and air is
directly filled in the tire. A tube type tire has a
tube inside the tire and the tube maintains the air
pressure.
9 Radial tires or biasply tires : A radial tire has
“RADIAL” on the sidewall. A tire not marked with
“RADIAL” is a bias −ply tire.

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546
DOT and Tire Identification Number (TIN)
63SA11a
The illustration indicates typical DOT and Tire
Identification Number (TIN)
1“DOT” symbol
2Tire Identification Number (TIN)
3Tire manufacturer’s identification mark
4Tire size code
5Manufacturer’s optional tire type code
(3 or 4 letters)
6Manufacturing week
7Manufacturing year
The “DOT” symbol certifies that the tire conforms to
applicable Federal Motor Vehicle Safety Standards.
Tire size
63ca01
The illustrations indicate typical tire sizes.
1Tire use (P=Passenger car, T=Temporary use)
2Section width (in millimeters)
3Aspect ratio (tire height to section width)
4Speed category (alphabet with one letter)
5Tire construction code
(R=Radial, D=Diagonal)
6Wheel diameter (in inches)
7Load index (2 digits or 3 digits)
8Speed symbol (alphabet with one letter)

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G63005
 1Section width
2Tire height
3Wheel diameter
Name of each section of tire
63sa14
 1Bead
2Sidewall
3Shoulder
4Tread
5Belt
6Inner liner
7Reinforcing rubber
8Carcass
9Rim lines
10Bead wires
11Chafer