2015 Lexus GX460 wheel

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GX460_OM_OM60L72U_(U)4-5. Using the driving support systems
4
Driving
Downhill assist control system
Shift the “DAC” switch to ON. The
downhill assist control system indicator
light comes on and the system will
operate.
When the system is in
operation, the slip
indicator light will flash, and the stop
lights/high mounted stop lights will be lit.
Shift the “DAC” switch to OFF while the system is in operation. The downhill
assist control system indicator will flash as the system gradually ceases operation,
and will turn off when the system is fully off.
Shift the “DAC” switch to ON while the downhill assist control system indicator is
flashing to start the system again.
: If equipped
The downhill assist control system helps to prevent excessive speed on steep
downhill slopes.
The system will operate when the vehicl e is traveling under 15 mph (25 km/h)
and the four-wheel drive control switch is in the L4 position.
System operation
Turning off the system

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GX460_OM_OM60L72U_(U)4-5. Using the driving support systems
■Operating tips
The system will operate when the shift lever is
in a position other than P, however to make
effective use of the system it is recommended that the shift lever be shifted to 2 or 1 range
of S mode.
■If the four-wheel drive control switch is in H4
The system does not operate.
■When the downhill assist control system is operated continuously
This may cause the brake actuator to overheat. In this case, the downhill assist control
system will stop operating, a buzzer will sound and the downhill assist control system
indicator will start flashing, and the “TRAC O FF” will be shown on the multi-information
display. Refrain from using the system until the downhill assist control system indicator
stays on and the message goes off. (The vehicl e can be driven normally during this time.)
■Sounds and vibrations caused by the downhill assist control system
●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 downhill assist control system.
●Either of the following conditions may occur when the downhill assist control system is
operating. None of these are indicators 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.
■System malfunction
●The downhill assist control system indicator does not come on when the engine switch
is turned to IGNITION ON mode.
●The downhill assist control system indicato r does not come on when the “DAC” switch
is pressed.
●The slip indicator comes on.
In the above cases, have your vehicle checked by your Lexus dealer.
CAUTION
■When using downhill assist control system
Do not rely overmuch on the downhill assist control system. This function does not
extend the vehicle’s performance limitations. Always thoroughly check the road condi-
tions, and drive safely.
■The system may not operate on the following surfaces, which may lead to an accident
causing death or serious injury
●Slippery surfaces such as wet or muddy roads
●Icy surface
●Unpaved roads

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GX460_OM_OM60L72U_(U)4-5. Using the driving support systems
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Driving
Driving assist systems
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if the brakes are
applied while driving on a slippery road surface
◆Multi Terrain ABS (Anti-lock Brake System) (vehicles with a Multi-terrain
Select system)
Helps to prevent wheel lock when the brakes are applied suddenly, or if the brakes are
applied while driving on a slippery road su
rface, or in off-road conditions (such as
rough roads, sand and mud)
The Multi Terrain ABS operates in synchr onization with the Multi-terrain Select
◆Brake assist
Generates an increased level of braking force after the brake pedal is depressed
when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on slippery
road surfaces
◆TRAC (Traction Control) for H4 position
Helps to maintain drive power and prevent the drive wheels from spinning when start-
ing the vehicle or accelerating on slippery roads
To help enhance driving safety and performance, the following systems oper-
ate automatically in response to various driving situations. Be aware, however,
that these systems are supplementary and should not be relied upon too
heavily when operating the vehicle.

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GX460_OM_OM60L72U_(U)4-5. Using the driving support systems
◆Active TRAC (Traction Control) for L4 position*
Helps to maintain drive power and prevent
the 4 wheels from spinning when starting
the vehicle or accelerating on slippery roads, or in off-road conditions
◆Hill-start assist control (if equipped)
Helps to prevent the vehicle from rolling backward when starting on an incline or slip-
pery slope
◆KDSS (Kinetic Dynamic Suspension System)
KDSS helps to enhance ride comfort and ha ndling response by using a hydraulic con-
trol system to control the suspension stabiliz er bars in response to road surface and
driving conditions during cornering or off-road driving
◆PCS (Pre-Collision system) (if equipped)
 P. 3 6 2
◆Trailer Sway Control
Helps the driver to control trailer sway by selectively applying brake pressure for indi-
vidual wheels and reducing engine to rque when trailer sway is detected.
Trailer Sway Control is part of the VSC system and will not operate if VSC turned off
or experiences a malfunction.
*: The function only works in vehicles with Multi-terrain Select when Multi-terrain
Select is switched on
If the vehicle is in danger of slipping or
rolling backward when starting on an
incline, or if any of the drive wheels
spins, the slip indicator light flashes to
indicate that the TRAC or Active
TRAC/VSC/Trailer Sway Control/hill-
start assist control systems are operat-
ing.
A buzzer (intermittent) sounds to indicate that VSC is operating.
The stop lights and high mounted stoplight tu rn on when the hill-start assist control
system is operating.
When the TRAC or Active TRAC/VSC /Trailer Sway Control/hill-start
assist control systems are operating

GX460_OM_OM60L72U_(U)
3474-5. Using the driving support systems
4
Driving
If the vehicle gets stuck in fresh snow or mud, the TRAC or Active TRAC/VSC/
Trailer Sway Control systems may reduce power from the engine to the wheels.
You may need to turn the system off to enable you to rock the vehicle in order to
free it.
■Turning off TRAC or Active TRAC system only
To turn the TRAC or Active TRAC
system off, quickly press and release
the switch.
The “TRAC OFF” will be shown on
the multi-information display.
Press the switch again to turn the sys-
tem back on.
■Turning off both TRAC or Active TRAC and VSC/Trailer Sway Control sys-
tems
To turn the TRAC or Active TRAC
and VSC/Trailer Sway Control sys-
tems off, press and hold the switch
for 3 seconds and more while the
vehicle is stopped.
The VSC OFF indicator light will
come on and the “TRAC OFF” will
be shown on the multi- information
display.
Press the switch again to turn the sys-
tem back on.
■When the “TRAC OFF” is displayed on the multi-information display even if the VSC
OFF switch has not been pressed
TRAC/Active TRAC, hill-start assist control, downhill assist control and Crawl Control
cannot be operated. Contact your Lexus dealer.
■Hill-start assist control operation conditions
●The shift lever is in D or S.
●The brake pedal is not depressed.
Disabling the TRAC or Active TRAC/VSC/Trailer Sway Control sys-
tems

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GX460_OM_OM60L72U_(U)4-5. Using the driving support systems
CAUTION
■Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load capac-
ity. In addition, make sure that the tires are inflated to the recommended tire inflation
pressure level.
The ABS/Multi Terrain ABS, TRAC/Active
TRAC and VSC/Trailer Sway Control will
not function correctly if different tires are installed on the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modi fying the suspension will affect the driving
assist systems, and may caus e the system to malfunction.
■Trailer Sway Control precaution
The Trailer Sway Control system is not able to reduce trailer sway in all situations.
Depending on many factors such as the condit ions of the vehicle, trailer, road surface,
and driving environment, the Trailer Sway Co ntrol system may not be effective. Refer to
your trailer owner’s manual for information on how to tow your trailer properly.
■If trailer sway occurs
Observe the following precautions.
Failing to do so may caus e death or serious injury.
●Firmly grip the steering wh eel. Steer straight ahead.
Do not try to control trailer swaying by turning the steering wheel.
●Begin releasing the accelera tor pedal immediately but very gradually to reduce
speed.
Do not increase speed. Do not apply vehicle brakes.
If you make no extreme correction with the steering or brakes, your vehicle and trailer
should stabilize. ( P. 1 8 0 )

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GX460_OM_OM60L72U_(U)4-6. Driving tips
Accelerate the vehicle slowly, keep a safe distance between you and the vehicle
ahead, and drive at a reduced speed
suitable to road conditions.
Park the vehicle and move the shift lever to P without setting the parking brake.
The parking brake may freeze up, preventing it from being released. If necessary,
block the wheels to prevent in advertent sliding or creeping.
Use the correct tire chain size when mounting the snow chains.
Chain size is regulated for each tire size. Side chain
(0.20 in. [5 mm] in diameter)
Cross chain
(0.25 in. [6.3 mm] in diameter)
Regulations regarding the use of tire chains vary depending on location and type
of road. Always check local regulations before installing chains.
■Tire chain installation
Observe the following precautions wh en installing and removing chains:
●Install and remove tire chains in a safe location.
●Install tire chains on the rear tires. Do not install tire chains on the front tires.
●Install tire chains on rear tires as tightly as possible. Retighten chains after driving 1 /4 -
1 /2 mile (0.5 - 1.0 km).
●Install tire chains following the instru ctions provided with the tire chains.
When driving the vehicle
When parking the vehicle
Selecting tire chains
1
2
Regulations on the use of tire chains

GX460_OM_OM60L72U_(U)
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4
Driving
CAUTION
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of vehicle control and cause death or serious injury.
●Use tires of the specified size.
●Maintain the recommended level of air pressure.
●Do not drive in excess of 75 mph (120 km/h), regardless of the type of snow tires
being used.
●Use snow tires on all, not just some wheels.
●Do not use LDA (Lane Departure Alert) system. (if equipped)
■Driving with tire chains
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in the vehicle being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed limit specified for the tire chains being used, or 30
mph (50 km/h), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden acceleration, ab rupt steering, sudden braking and shifting operations
that cause sudden engine braking.
●Slow down sufficiently before entering a cu rve to ensure that vehicle control is main-
tained.
●Do not use LDA (Lane Departure Alert) system. (if equipped)
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow tires from Lexus dealers or legitimate tire
retailers.
This is because the removal and attachment of snow tires affects the operation of the
tire pressure warning valves and transmitters.
■Fitting tire chains
The tire pressure warning valves and transmitters may not function correctly when tire
chains are fitted.