2008 Lexus GX470 Owner's Manual

160
2-4. Using other driving systems
When the VSC/TRAC/hill-start assist control systems are operating
If the vehicle is in danger of slip-
ping, rolling backwards when
starting on an incline, or if the rear
wheels spin, the slip indicator light
flashes to indicate that the VSC/
TRAC/hill-start assist control sys-
tems have been engaged.
A buzzer (intermittent) sounds to
indicate that VSC is operating.
The stop lights and high mounted
stoplight turn on when the hill-start
assist control system is operating.
The slip indicator light flashes as
well when ABS is operating.
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC and hill-start
assist control systems
●A sound may be heard from the engine compartment when the engine is
started or just after the vehicle begins to move. This sound does not indicate that
a malfunction has occurred in any of these systems.
●Any of the following conditions may occur when the above systems are operat-
ing. None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
■Hill-start assist control is operational when
●The shift lever is in any of the positions “D”, “4”, “3”, “2” or “L”.
●The brake pedal is not depressed.

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2-4. Using other driving systems
2
When driving
CAUTION
Any of the following conditions may result in an accident which could cause death or
serious injury:
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded.
●The vehicle hydroplanes while driving at high speed on the wet or slick road.
■Stopping distance when the ABS is operating on the wet or slick roads
The ABS is not designed to shorten the vehicle’s stopping distance. Always main-
tain a safe distance from the vehicle in front of you in the following situations.
●When driving on dirt, gravel or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or roads with uneven roads
■TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the TRAC is operating.
Do not drive the vehicle in conditions where stability and power may be lost.
■The hill-start assist control may not operate effectively when
●On steep inclines.
●On icy surfaces.
■When the VSC is activated
The slip indicator light flashes and a warning buzzer sounds. Always drive carefully.
Reckless driving may cause an accident. Exercise particular care when the indica-
tor light flashes and a buzzer sounds.

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2-4. Using other driving systems
CAUTION
■Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the specified tire pres-
sure level.
The ABS and VSC will not function correctly if different tires are fitted on the vehi-
cle.
Contact your Lexus dealer for further information when replacing tires or wheels.
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will affect the driv-
ing assist systems, and may cause the system to malfunction.

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2
When driving
2-5. Driving information
Off-road precautions
Off-road vehicle feature● Specific design characteristics give it a higher center of gravity than
ordinary passenger cars. This vehicle design feature causes this type of
vehicle to be more likely to rollover. And, utility vehicles have a signifi-
cantly higher rollover rate than other types of vehicles.
● An advantage of the higher ground clearance is a better view of the
road allowing you to anticipate problems.
● It is not designed for cornering at the same speeds as ordinary passen-
ger cars any more than low-slung sports cars designed to perform sat-
isfactorily under off-road conditions. Therefore, sharp turns at
excessive speeds may cause rollover.
This vehicle belongs to the utility vehicle class, which has higher
ground clearance and narrower tread in relation to the height of its
center of gravity to make it capable of performing in a wide variety of
off-road applications.

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2-5. Driving information
CAUTION
■Off-road vehicle precautions
Always observe the following precautions to minimize the risk of serious personal
injury or damage to your vehicle:
●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.
●Avoid sharp turns or abrupt maneuvers, if at all possible.
Failure to operate this vehicle correctly may result in loss of control or vehicle roll-
over causing death or serious injury.
●Loading cargo on the roof luggage carrier will make the center of the vehicle
gravity higher. Avoid high speeds, sudden starts, sharp turns, sudden braking or
abrupt maneuvers, otherwise it may result in loss of control or vehicle rollover
due to failure to operate this vehicle correctly.
●Always slow down in gusty crosswinds. Because of its profile and higher center of
gravity, your vehicle is more sensitive to side winds than an ordinary passenger
car. Slowing down will allow you to have better control.
●Do not drive horizontally across steep slopes. Driving straight up or straight down
is preferred. Your vehicle (or any similar off-road vehicle) can tip over sideways
much more easily than forward or backward.

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2-5. Driving information
2
When driving
Off-road drivingWhen driving your vehicle off-road, please observe the following precau-
tions to ensure your driving enjoyment and to help prevent the closure of
areas to off-road vehicles.
● Drive your vehicle only in areas where off-road vehicles are permitted
to travel.
● Respect private property. Get owner’s permission before entering pri-
vate property.
● Do not enter areas that are closed. Honor gates, barriers and signs
that restrict travel.
● Stay on established roads. When conditions are wet, driving tech-
niques should be changed or travel delayed to prevent damage to
roads.
■Additional information for off-road driving
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

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2-5. Driving information
CAUTION
■Off-road driving precautions
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 off-road. 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.
●When driving off-road or in rugged terrain, do not drive at excessive speeds,
jump, make sharp turns, strike objects, etc. This may cause loss of control or vehi-
cle rollover causing death or serious injury. You are also risking expensive dam-
age to your vehicle’s suspension and chassis.
NOTICE
■To prevent the water damage
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 entering the automatic transmission will cause deterioration in shift quality,
locking up of your transmission accompanied by vibration, and ultimately dam-
age.
●Water can wash the grease from wheel bearings, causing rusting and premature
failure, and may also enter the differentials, transmission and transfer case, reduc-
ing the gear oil’s lubricating qualities.

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2-5. Driving information
2
When driving
NOTICE
■When you drive through water
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.
■Inspection after off-road driving
●Sand and mud that has accumulated in brake drums and around brake discs may
affect braking efficiency and may damage brake system components.
●Always perform a maintenance inspection after each day of off-road driving that
has taken you through rough terrain, sand, mud, or water. For scheduled mainte-
nance information, refer to the “Warranty and Services Guide/Owner’s Manual
Supplement/Scheduled Maintenance”.