2003 Lexus GX470 tire type

SECTION 3 – 1
296
STARTING AND DRIVING
Starting and driving
Three−way catalytic converters297
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Engine exhaust caution 298
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Before starting the engine 299
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Ignition switch with steering lock 300
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Parking brake 301
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How to start the engine 302
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Automatic transmission 303
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Four−wheel drive system 309
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Cruise control 312
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Rear height control air suspension 315
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Electronic modulated suspension 320
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Active traction control system 321
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Vehicle skid control system 323
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Downhill assist control system 326
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Hill −start assist control system 329
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Brake system 331
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Brake pad wear limit indicators 335
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Limited −slip differential 336
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Types of tires 336
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STARTING AND DRIVING
324
Only use tires of specified size. The size,
manufacturer, brand and tread pattern for all 4 tires
should be the same. If you use the tires other than
specified, or different type or size, the vehicle skid
control system may not function correctly. When
replacing the tires or wheels, contact your Lexus
dealer.
 In situations where the road surface is covered with
ice or snow, your vehicle should be fitted with snow
tires or tire chains.
 Slip indicator light
If the vehicle is going to skid during driving, the slip indicator
light blinks and an alarm sounds intermittently. Special care
should be taken while driving. The slip indicator light comes on for a few seconds when the
ignition key is turned to “ON”. If the indicator light does not
come on when the ignition is turned on, contact your Lexus
dealer.
Pushing the center differential lock switch automatically
turns
the vehicle skid control system off. At this time, the
“VSC OFF” indicator comes on with the center differential
lock indicator light.
“VSC OFF” indicator light comes on for a few seconds when
the ignition key is turned to “ON”. It will come on again when
you push the center differential lock switch to turn off the
system.
In the following cases, contact your Lexus dealer:
 The indicator light does not come on when the ignition key
is turned “ON”.

STARTING AND DRIVING
336
LIMITEDSLIP DIFFERENTIAL
Your Lexus is equipped with a limited−slip center differential
(transfer).
If one wheel − either front or rear − begins to spin, the transfer
(limited −slip center differential) is designed to aid traction by
automatically transmitting driving force to the wheels on the
other drive axle. It transmits driving force to the front wheels
if a rear wheel spins, and to the rear wheels if a front wheel
spins.
CAUTION
Do not start or run the engine while your vehicle is
supported by a jack. The vehicle could be driven off the
jack and could pose a danger or result in serious injury.
NOTICE
Use only a spare tire of the same size, construction and
load capacity as the original tires on your Lexus
because damage to the limitedslip differential could
possibly occur with another tire type.
TYPES OF TIRES
Determine what kind of tires your vehicle is originally equipped
with.
1. Summer tires
Summer tires are high −speed capability tires best suited to
highway driving under dry conditions.
Since summer tires do not have the same traction performance
as snow tires, summer tires are inadequate for driving on
snow−covered or icy roads. For driving on snow −covered or
icy roads, we recommend using snow tires. If installing snow
tires, be sure to replace all four tires.
2. All season tires
All season tires are designed to provide better traction in snow
and to be adequate for driving in most winter conditions, as well
as for use all year round.
All season tires, however, do not have adequate traction
performance compared with snow tires in heavy or loose snow.
Also, all season tires fall short in acceleration and handling
performance compared with summer tires in highway driving.

DRIVING TIPS
352
Tires
Ensure that your vehicle’s tires are properly inflated. Adjust
the tire pressure to the recommended cold tire pressure
indicated below.
Tire pressure: 220 kPa (2.2 kgf/cm
2 or bar, 32 psi)
 The trailer tires should be inflated to the pressure
recommended by the trailer manufacturer in respect to the
total trailer weight.
Trailer lights
 Socket for trailer lights
Your vehicle is equipped with a wire harness stored in the rear
end underbody. Models with tow hitch receiver are fitted with
a socket for trailer lights under the rear bumper. Use either of
them to connect and operate the trailer lights. However, the
trailer lights must comply with federal, state/provincial and
local regulations. See your local recreational vehicle dealer or
rental agency for the correct type of wiring and relays for your
trailer. Check for correct operation of the turn signals and stop
lights each time you hitch up. Direct splicing may damage your
vehicle’s electrical system and cause a malfunction of your
lights.
Breakin schedule
Lexus recommends that you do not tow a trailer with a new
vehicle or a vehicle with any new power train component
(engine, transmission, differential, wheel bearing, etc.) for the
first 800 km (500 miles) of driving.

CHASSIS
436Warning: The traction grade assigned to this tire is based on
braking (straight ahead) traction tests and does not include
cornering (turning) traction.
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 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 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.
Tire selection
When replacing a tire, use a tire of the same size and
construction, and the same or greater load capacity as the
originally installed tires. Also, all the tires must be the
same brand and have the same tread patterns.
Using any other size or type of tire may seriously affect
handling, ride, speedometer/odometer calibration, ground
clearance, and clearance between the body and tires or snow
chains.
CAUTION
Observe the following instructions. Otherwise, an
accident may occur resulting in death or serious
injuries.
 Do not mix radial, bias belted, or biasply tires on
your vehicle, as this may cause dangerous handling
characteristics resulting in loss of control.
 Do not use tires other than the manufacturer’s
recommended size, as this may cause dangerous
handling characteristics resulting in loss of control.
 Do not use tires of different brands, sizes,
construction or tread patterns, as this may cause
dangerous handling characteristics result ing in loss
of control.

CHASSIS
437
INSTALLING SNOW TIRES ANDCHAINS
When to use snow tires or chains
Snow tires or chains are recommended when driving on
snow or ice.
On wet or dry roads, conventional or radial tires provide better
traction than snow or studded tires.
Snow tire selection
If you need snow tires, select tires of the same size,
construction and load capacity as the originally installed
tires. Also, all the tires must be the same brand and have
the same tread patterns.
Do not use tires other than stated above. Since your vehicle
has radial tires as original equipment, make sure your snow
tires also have radial construction. Do not install studded tires
without first checking local regulations for possible restrictions.
CAUTION
Observe the following instructions. Otherwise, an
accident may occur resulting in death or serious
injuries.
Do not use snow tires other than the manufacturer’s
recommended size, as this may cause dangerous
handling characteristics resulting in loss of control.
 Do not use snow tires of different brands, sizes,
construction or tread patterns, as this may cause
dangerous handling characteristics resulting in loss
of control.
Snow tire installation
Snow tires should be installed on all wheels.
Installing snow tires on the rear wheels only can lead to an
excessive difference in road grip capability between the front
and rear tires which could cause loss of vehicle control.
CAUTION
 Do not drive with the snow tires incorrectly inflated.
 Never drive over 105 km/h (65 mph) with any type of
snow tires.

CHASSIS
438
Tire chain selection
 1 Side chain2 Cross chain
Use the tire chains of correct size.
For P265/65R17 tires, use the following type chains. mm (in.)
A: Diameter of side chain 5.0 (0.20)
B: Width of side chain 18.0 (0.71)
C: Length of side chain 46.0 (1.81)
D: Width of cross chain 22.6 (0.89)
E: Length of cross chain 38.1 (1.5)
F: Diameter of cross chain 6.3 (0.25) Regulations regarding the use of tire chains vary
according to location or type of road. Always check the
local regulations before installing chains.
NOTICE
If the wrong combination of tire and chain is used, the
chains could damage the vehicle body.

CHASSIS
439
Chain installation
Install the chains on the rear tires as tightly as possible.
Do not use tire chains on the front tires. Retighten chains
after driving 0.5 1.0 km (1/4 1/2 mile).
When installing chains on your tires, carefully follow the
instructions of the chain manufacturer.
CAUTION
Do not exceed 50 km/h (30 mph) or the chain
manufacturer’s recommended speed limit,
whichever is lower.
 Drive carefully avoiding bumps, holes, and sharp
turns, which may cause the vehicle to bounce.
 Avoid sharp turns or lockedwheel braking, as use of
chains may adversely affect vehicle handling.
 When driving with chains installed, be sure to drive
carefully. Slow down before entering the curves to
avoid losing control of the vehicle. Otherwise an
accident may occur.
NOTICE
When jacking up or installing tire chains, be sure to turn
off the rear height control air suspension with the
“HEIGHT CONTROL OFF” switch and stop the engine.
Otherwise, the vehicle height may change because of
the automatic leveling function resulting in accident.
REPLACING WHEELS
When to replace your wheels
If you have wheel damage such as bending, cracks or
heavy corrosion, the wheel should be replaced.
If you fail to replace damaged wheels, the tire may slip off the
wheel or cause loss of handling control.
Replacement with used wheels is not recommended as they
may have been subjected to rough treatment or high mileage
and could fail without warning. Also, bent wheels which have
been straightened may have hidden structural damage and
therefore should not be used. Never use an inner tube in a
leaking wheel which is designed for a tubeless tire.
Wheel selection
When replacing wheels, care should be taken to ensure
that they are equivalent to those removed in load capacity,
diameter, rim width, and offset.
Correct replacement wheels are available at your Lexus
dealer.
A wheel of a different size or type may adversely affect
handling, wheel and bearing life, brake cooling,
speedometer/odometer calibration, stopping ability, headlight
aim, bumper height, vehicle ground clearance, and tire or snow
chain clearance to the body and chassis.