2006 Lexus GX470 Suspension System

OCCUPANT RESTRAINT SYSTEMS
165
Do not attach a microphone or any other device or
object around the area where the curtain shield
airbag activates such as on the windshield glass,
side door glass, front and rear pillars, roof side rail
and assist grips. When the curtain shield airbag
inflates, the microphone or other device or object will
be thrown away with great force or the curtain shield
airbag may not activate correctly, resulting in death
or serious injury.
 Do not hook a hanger , heavy or sharp pointed objects
on the coat hook. If the curtain shield airbag inflates,
those items will be thrown away with great force or
the curtain shield airbag may not activate correctly,
resulting in death or serious injury. When you hang
clothes, hang them on the coat hook directly.
 Do not use seat accessories which cover the parts
where the side airbags inflate. Such accessories may
prevent the side airbags from activating correctly,
causing death or serious injury.
 Do not modify or replace the seats or upholstery of
the seats with side airbags. Such changes may
prevent the side airbag system from activating
correctly, disable the system or cause the side
airbags to inflate accidentally, resulting in death or
serious injury.
 Do not disassemble or repair the front and rear pillars
and roof side rail containing the curtain shield
airbags. Such changes may disable the system or
cause the curtain shield airbags to inflate
accidentally, resulting in death or serious injury.
 Do not modify or change the suspension system.
Such changes may cause the curtain shield airbags
to inflate accidentally, which could result in death or
serious injury . Consult your Lexus dealer about any
repair and modification.
 Do not use tires or wheels other than the
manufacture’s recommended size. Such a use may
cause the curtain shield airbags and seat belt
pretensioners to inflate accidentally, which could
result in death or serious injury. For details, see
“Checking and replacing tires” on page 538.

OCCUPANT RESTRAINT SYSTEMS
166
Do not place luggage heavier than specified on the
roof luggage carrier. Such luggage may cause the
curtain shield airbags and seat belt pretensioners to
inflate accidentally, which could result in death or
serious injury. For details, see “Roof luggage
carrier” on page 107.
Failure to follow these instructions can result in death
or serious injury. Consult your Lexus dealer about any
repair and modification.
If you wish to modify your vehicle for a person with a
physical disability, consult your Lexus dealer. It may
dangerously interfere with the SRS side airbags and
curtain shield airbags operation.
NOTICE
Do not perform any of the following changes without
consulting your Lexus dealer. Such changes can
interfere with proper operation of the SRS side airbag
and curtain shield airbag system in some cases.
 Installation of electronic devices such as a mobile
twoway radio, cassette tape player or CD player
 Modification of the suspension system
 Modification of the structure of the passenger
compartment
 Repairs made on or near the console or front seat
The indicator comes on when the ignition key is turned to
the “ON” position. It goes off after about 6 seconds. This
means the SRS side airbags and curtain shield airbags are
operating properly.
This warning light system monitors the airbag sensor
assembly, front airbag sensors, side and curtain shield airbag
sensor assemblies, curtain shield airbag sensor assemblies,
driver’s seat position sensor, driver’s seat belt buckle switch,
front passenger occupant classification system, “AIRBAG ON”
indicator light, “AIRBAG OFF” indicator light, front passenger’s
seat belt buckle switch, front seat belt pretensioner
assemblies, inflators, warning light, “RSCA OFF” indicator
light, interconnecting wiring and power sources. (For details,
see “Service reminder indicators and warning buzzers” on
page 51 for instructions.)

SECTION 3 – 1
341
STARTING AND DRIVING
Starting and driving
Three−way catalytic converters342
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Engine exhaust caution 343
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Before starting the engine 344
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Ignition switch 345
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Parking brake 347
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. . . . . .
How to start the engine 348
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Automatic transmission 349
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Four−wheel drive system 356
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Rear view monitor system 358
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Cruise control 362
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Rear height control air suspension 366
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Electronic modulated suspension 371
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Active traction control system 372
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Vehicle stability control system 375
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Downhill assist control system 377
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Hill −start assist control 380
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Brake system 383
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Tire pressure warning system 387
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Brake pad wear limit indicators 394
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Limited −slip differential 395
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STARTING AND DRIVING
369
(d) Turning off the rear height control airsuspension
To turn off the rear height control air suspension with the
vehicle stopped, push the “HEIGHT CONTROL OFF”
switch. The height control “OFF” indicator light comes on
and the vehicle height is fixed in the same mode as the
height control switch is pushed.
This status is memorized in the system even after the engine
is stopped.
If you push the switch again, the height control “OFF” indicator
light goes out and the rear height control air suspension is
turned on.
Even after the rear height control air suspension is turned off
with the “HEIGHT CONTROL OFF” switch, if the vehicle speed
exceeds 30 km/h (19 mph), the rear height control air
suspension automatically selects the “N” mode.
CAUTION
If you drive through deep water over about 700 mm (28
in.) in depth, put the vehicle height in the “HI” mode with
the height select switch and then turn off the rear height
control air suspension by pushing the “HEIGHT
CONTROL OFF” switch.
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.
 If your vehicle must be towed, put the vehicle height
in the “N” mode and turn off the rear height control air
suspension. Otherwise, the vehicle height may
change because of the automatic leveling function
resulting in accident.
 If your vehicle gets ditched, turn off the rear height
control air suspension with the “HEIGHT CONTROL
OFF” switch. Otherwise, the vehicle height may
change because of the automatic leveling function
resulting in accident.

STARTING AND DRIVING
370
(e) Height control indicator lights
1Height control indicator lights
2Height control “OFF” indicator light
When the ignition switch is turned on, all the indicator lights
come on. Only the indicator light showing the present mode
remains on and all other lights go off after a few seconds. This
means the system operates correctly.
When you change the vehicle height mode, the indicator lights
change as follows:
When changing the vehicle height from the “N” mode to
“HI”:
1. The “N” mode indicator light goes off and the “HI” mode
indicator light blinks.
2. After the vehicle height control reaches the “HI” mode, the
“HI” mode indicator light remains on. If the underbody of the vehicle has touched the surface on
bumpy roads or the area around the rear suspension is
coated with ice, the height control suspension will not
operate and the indicator lights change as follows:
1. The present mode indicator light goes off and the selected
mode indicator light blinks.
2. The selected mode indicator light goes off. (The vehicle
height does not change.) The present mode indicator light
comes on again.
Height control “OFF” indicator light:
When the ignition
switch is turned on, this light comes on. If it goes out after a few
seconds, the rear height control air suspension operates
correctly. If you push the “HEIGHT CONTROL OFF” switch,
the rear height control air suspension is turned off. The height
control “OFF” indicator light comes on.
In the following cases, there is a problem somewhere in the
rear height control air suspension. Although there is no
problem to continue normal driving, have the rear height
control air suspension checked by your Lexus dealer as soon
as possible.
 The height control “OFF” indicator light does not come on
when the ignition switch is turned on.
 The height control “OFF” indicator light blinks.

DRIVING TIPS
403
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”.

DRIVING TIPS
413
Trailer lights
Your vehicle is equipped with a wire harness stored in the rear
end underbody. 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.
Maintenance
 If you tow a trailer, your vehicle will require more frequent
maintenance due to the additional load. For this
information, please refer to the scheduled maintenance
information in the “Owner’s Manual Supplement/Scheduled
Maintenance”.
 Retighten all fixing bolts of the towing ball and bracket after
approximately 1000 km (600 miles) of trailer driving.
Connecting a trailer
Stop your vehicle and a trailer in line and perform the following:
1. Put the rear height control air suspension in the “LO” (low)
mode. Turn the ignition switch off or push the “HEIGHT
CONTROL OFF” switch to turn off the rear height control air
suspension.
2. Connect a trailer.
3. Turn the ignition switch on or push the “HEIGHT CONTROL
OFF” switch to turn on the rear height control air suspension.
Select the “N” (normal) mode with the height select switch.
Disconnecting a trailer
Stop your vehicle and a trailer in line and perform the following:
1. Put the rear height control air suspension in the “LO” (low)
mode. (Make sure the vehicle height is in the “LO” (low) mode
by pushing the height select switch on the “
” side.)
2. Turn the ignition switch off or push the “HEIGHT CONTROL
OFF” switch to turn off the rear height control air suspension.
3. Set the supporting leg of a trailer on the ground and raise the
hitch by 100 mm (4 in.).
4. Turn the ignition switch on or push the “HEIGHT CONTROL
OFF” switch to turn on the rear height control air suspension.

IN CASE OF AN EMERGENCY
436
To remove the spare tire:
1. Open the back door and remove the spare tire
carrier lid using a flat−bladed screwdriver.
2. Insert the end of the jack handle extension into the
lowering screw and put a cloth between the jack
handle extension and rear bumper to protect the
bumper surface.
3. Turn the jack handle counterclockwise until the
spare tire completely lowered to the ground. Make
sure the handle remains firmly fitted onto the jack
handle extension. Vehicles with kinetic dynamic suspension system —
When lowering the spare tire, make sure the spare
tire does not to interfere with the suspension
components. If interference occurs, raise the spare
tire, and pull it toward the rear of the vehicle, and
start again.
4. After the tire is lowered completely to the ground,
remove the holding bracket.