wheel Lexus GX470 2003 How To Use This Manual / LEXUS 2003 GX470 (OM60979U) Owner's Guide

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”.

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326
DOWNHILL ASSIST CONTROLSYSTEM
The downhill assist control system is a system that
assists the deceleration of the engine brake when you
drive down a steep hill. When you are driving down a hill
with the fourwheel drive control lever in the “L” position,
push the “DAC” switch to limit the vehicle’s acceleration.
If the vehicle is traveling at a speed of 25 km/h (15 mph) or
less, you can descend at a constant speed.
CAUTION
Do not rely excessively on the downhill assist control
system. It may not be able to maintain a low speed over
road surfaces or offroad surfaces on which sliding can
easily occur, such as extremely steep slopes or icy or
muddy roads.
Turning on the system
1. Shift the fourwheel drive control lever to the “L”
position.
The system will not operate if the four −wheel drive control lever
is in the “H” position.
2. In order to make full use of the engine brake, putting the
transmission in “L” or “2” is recommended.
The system will operate even if the transmission selector lever
is in “D”, “4”, “3” or “N”. However, when it is in “L” or “2” the
engine brake can also be utilized enabling the system to
operate more effectively.
3. Push the “DAC” switch to turn the system on. The
downhill assist control system indicator light on the
instrument panel will come on.
If the downhill assist control system indicator light flashes, the
transmission selector lever may be in “N” or four −wheel drive
control lever may be in the “H” position.

STARTING AND DRIVING
332You may hear a small sound in the engine compartment after
the engine is started or the brake pedal is depressed
repeatedly. This is a pump pulsating sound of the brake
system, and it is not a malfunction.
CAUTION

Do not pump the brake pedal if the engine stalls.
Each push on the pedal uses up your brake fluid
pressure reserve.
 Even if the power assist is completely lost, the brakes
will still work. But you will have to push the pedal
hard, much harder than normal. And your braking
distance will be longer.
Antilock brake system
The antilock brake system is designed to automatically
help prevent lockup of the wheels during a sudden brake
or braking on slippery road surfaces. This assists in
providing directional stability and steering performance
of the vehicle under these circumstances.
Effective way to press the ABS brake pedal: When the
anti−lock brake system function is in action, you may feel the
brake pedal pulsating and hear a noise. In this situation, to
let the anti−lock brake system work for you, just hold the
brake pedal down more firmly. Do not pump the brake in a
panic stop. This will result in reduced braking performance.
The anti−lock brake system becomes operative after the
vehicle has accelerated to a speed in excess of approximately
10 km/h (6 mph). It stops operating when the vehicle
decelerates to a speed below approximately 5 km/h (3 mph).
Depressing the brake pedal on slippery road surfaces such as
on the manhole cover, the steel plate under the construction,
joints in the bridge, etc. on a rainy day tends to activate the
anti−lock brake system.
You may hear a click or motor sound in the engine
compartment for a few seconds when the engine is started or
just after the vehicle begins to move. This means that the
anti−lock brake system is in the self −check mode, and does not
indicate a malfunction.
When the antilock brake system is activated, the
following conditions may occur. They do not indicate a
malfunction of the system:
 You may hear the anti −lock brake system operating and feel
the brake pedal pulsating and the vibrations of the vehicle
body and steering wheel. You may also hear the motor
sound in the engine compartment even after the vehicle is
stopped.
 At the end of the anti−lock brake system activation, the
brake pedal may move a little to the forward.

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333
CAUTION
Do not overestimate the antilock brake system:
Although the antilock brake system assists in
providing vehicle control, it is still important to drive
with all due care and maintain a moderate speed and
safe distance from the vehicle in front of you, because
there are limits to the vehicle stability and effectiveness
of steering wheel operation even with the antilock
brake system on.
If tires grip performance exceeds its capability, or if
hydroplaning occurs during high speed driving in the
rain, the antilock brake system does not provide
vehicle control.
Antilock brake system is not designed to shorten the
stopping distance: Always drive at the moderate speed
and maintain a safe distance from the vehicle in front of
you. Compared with vehicles without an antilock
brake system, your vehicle may require a longer
stopping distance in the following cases:
 Driving on rough, gravel or snowcovered roads.
 Driving with tire chains installed.
Driving over the steps such as the joints on the road.
 Driving on roads where the road surface is pitted or
has other differences in surface height.
Install all 4 tires of specified size at appropriate
pressure: The antilock brake system detects vehicle
speeds using the speed sensors for respective wheels’
turning speeds. The use of tires other than specified
may fail to detect the accurate turning speed resulting
in a longer stopping distance.

STARTING AND DRIVING
334“ABS” warning light
The light comes on when the ignition key is turned to the “ON”
position. If the anti−lock brake system and the brake assist
system work properly, the light turns off after a few seconds.
Thereafter, if either of the systems malfunctions, the light
comes on again.
When the “ABS” warning light is on (and the brake system
warning light is off), the anti
−lock brake system, the brake
assist system, the active traction control system and the
vehicle skid control system do/does not operate, but the brake
system still operates conventionally.
When the “ABS” warning light is on (and the brake system
warning light is off), the anti −lock brake system does not
operate so that the wheels could lock up during a sudden
braking or braking on slippery road surfaces. If either of the following conditions occurs, this indicates
a malfunction somewhere in the parts monitored by the
warning
light system. Contact your Lexus dealer as soon
as possible to service the vehicle.
 The light does not come on when the ignition key is turned
to the “ON” position, or remains on.
 The light comes on while you are driving.
A warning light turning on briefly during operation does not
indicate a problem.
CAUTION
If the “ABS” warning light remains on together with the
brake system warning light, immediately stop your
vehicle at a safe place and contact your Lexus dealer.
In this case, not only the antilock brake system will fail
but also the vehicle will become extremely unstable
during braking.
Either of the following conditions may occur, but do not
indicate the malfunction:
 The light may stay on for about 60 seconds after the ignition
key is turned to the “ON” position. It is normal if it turns off
after a while.
 Depressing the brake pedal repeatedly may turn on the
light. It is normal if it turns off after a few seconds.

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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.

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337
CAUTION
Do not mix summer and all season tires on your
vehicle as this can cause dangerous handling
characteristics, resulting in loss of control.
 Do not use tires other than the manufacturer’s
designated tires, and never mix tires or wheels of the
sizes different from the originals.

DRIVING TIPS
341
OPERATION IN FOREIGNCOUNTRIES
If you plan to drive your Lexus in another country ...
First, comply with the vehicle registration laws.
Second, confirm the availability of the correct fuel (unleaded
and minimum octane rating).
TIPS FOR DRIVING IN VARIOUS CONDITIONS
Always slow down in gusty crosswinds. This will allow you
much better control.
 Drive slowly onto curbs and, if possible, at a right angle.
Avoid driving onto high, sharp −edged objects and other
road hazards. Failure to do so can lead to severe tire
damage resulting in tire bursts.
Drive slowly when passing over bumps or travelling on a
bumpy road. Otherwise, the impact could cause severe
damage to the tires and/or wheels.
 When parking on a hill, turn the front wheels until they touch
the curb so that the vehicle will not roll. Apply the parking
brake, and p lace the transmission in “P”. If necessary, block
the wheels.
 Washing your vehicle or driving through deep water may get
the brakes wet. To see whether they are wet, check that
there is no traffic near you and then press the pedal lightly.
If you do not feel a normal braking force, the brakes are
probably wet. To dry them, drive the vehicle cautiously while
lightly pressing the brake pedal with the parking brake
applied. If they still do not work safely, pull to the side of the
road and call a Lexus dealer for assistance.

DRIVING TIPS
343
OFFROAD DRIVINGPRECAUTIONS
When driving your vehicle off −road, please observe the
following precautions to ensure your driving enjoyment and to
help prevent the closure of areas to off −road vehicles.
a. Drive your vehicle only in areas where off −road vehicles are
permitted to travel.
b. Respect private property. Get owner’s permission before
entering private property.
c. Do not enter areas that are closed. Honor gates, barriers
and signs that restrict travel.
d. Stay on established roads. When conditions are wet,
driving techniques should be changed or travel delayed to
prevent damage to roads.
For owners in U.S. mainland, Hawaii and Puerto Rico:
To obtain additional information pertaining to driving your
vehicle off −road, consult the following organizations.
 State and Local Parks and Recreation Departments
 State Motor Vehicle Bureau
 Recreational Vehicle Clubs
 U.S. Forest Service and Bureau of Land Management
CAUTION
Always observe the following precautions to minimize
the risk of serious personal injury or damage to your
vehicle:
Drive carefully when off the road. Do not take
unnecessary risks by driving in dangerous places.
 Do not grip the steering wheel spokes when driving
offroad. A bad bump could jerk the wheel and injure
your hands. Keep both hands and especially your
thumbs on the outside of the rim.
 Always check your brakes for effectiveness
immediately after driving in sand, mud, water or
snow.
 After driving through tall grass, mud, rock, sand,
rivers, etc., check that there is no grass, bush, paper,
rags, stone, sand, etc. adhering or trapped on the
underbody. Clear off any such matter from the
underbody. If the vehicle is used with these materials
trapped or adhering to the underbody, a breakdown
or fire could occur.
 In a rollover crash, an unbelted person is
significantly more likely to die than a person wearing
a seat belt. Therefore, the driver and all passengers
should fasten their seat belts whenever the vehicle is
moving.

DRIVING TIPS
344
When driving offroad or in rugged terrain, do not
drive at excessive speeds, jump, make sharp turns,
strike objects, etc. This may cause loss of control or
vehicle rollover causing death or serious injury. You
are also risking expensive damage to your vehicle’s
suspension and chassis.
NOTICE
 If driving through water, such as when crossing
shallow streams, first check the depth of the water
and the bottom of the river bed for firmness. Drive
slowly and avoid deep water.
 Take all necessary safety measures to ensure that
water damage to the engine or other components
does not occur.
Water entering the engine air intake will cause severe
engine damage.
Water can wash the grease from wheel bearings,
causing rusting and premature failure, and may also
enter the differentials, transmission and transfer
case, reducing the gear oil’s lubricating qualities.
 Sand and mud that has accumulated in brake drums
and around brake discs may affect braking ef ficiency
and may damage brake system components.
 Always perform a maintenance inspection after each
day of offroad driving that has taken you through
rough terrain, sand, mud, or water. For scheduled
maintenance information, refer to the “Owner’s
Manual Supplement / Scheduled Maintenance”.