2018 Lexus GX460 engine

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GX460_OM_OM60Q09U_(U)4-5. Using the driving support systems
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Driving
Rear height control air suspension∗
Height control OFF button
Height control switch
Operating the switch changes ve hicle rear height as follows:
Higher
Lower
Vehicle height can be adjusted only
when the engine is running.
The selected height mode will be
shown on the rear height control air
suspension display.
The selected mode will flash while the
height mode is being changed.
∗: If equipped
The rear height control air suspension allows the driver to control vehicle rear
height in order to adjust driving condit ions. Select the desired height with the
height control switch.
1
2
Selecting vehicle height
1
2

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GX460_OM_OM60Q09U_(U)4-5. Using the driving support systems
■Height modes
●N mode (normal mode): For ordinary driving
Normal height
●HI mode (high mode): For driving on bumpy roads
1.6 in. (40 mm) higher than the normal rear height
HI mode cannot be selected when vehicle speed exceeds 18 mph (30
km/h).
●LO mode (low mode): For the ease
of egress/ingress and loading luggage
0.8 in. (20 mm) lower than the normal rear height
LO mode cannot be selected when vehicle speed exceeds 7 mph (12 km/h).
When the height control OFF button is
pressed with the vehicle stopped, the
vehicle height is fixed at the current
height.
This status is memorized in the system
even after the engine is stopped.
The height can be adjusted by pressing
the height control OFF button again.
When vehicle speed exceeds 18 mph (30 km/h), the rear height control air suspen-
sion turns on automatically.
Disabling the height control

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Driving
■When HI mode is selected
The vehicle height will change to N mode when driving at the speeds of 18 mph (30 km/h).
Even if vehicle speed is then reduced to un der 18 mph (30 km/h), height will not return to
HI mode.
■When LO mode is selected
The vehicle height will change to N mode when vehicle speed exceeds 7 mph (12 km/h).
Even if vehicle speed is then reduced to un der 7 mph (12 km/h), height will not return to
LO mode.
■Automatic leveling function
Regardless of the number of occupants and the luggage load, vehicle height in any mode
is always adjusted to a fixed height by the automatic leveling function.
■The rear height control air suspension will not operate in the following cases:
●The underbody of the vehicle is touching the surface of the road.
●The area around the suspension is covered with ice.
■Even if you hear an operating noise
This does not indicate a problem in th e rear height control air suspension.
■Parking and stopping tips
●If you immediately stop the engine after off- road driving, or park the vehicle for a long
time, the vehicle height may gradually lower. When parking, make sure there is nothing
under the vehicle that may come in contact with the underbody. The vehicle will return
to the set height when the engine is started.
●The vehicle height may change as the temperature changes when the engine is
stopped. The vehicle will return to the set height when the engine is started.
■When lowering the vehicle
In order to prevent the vehicle height from rising as occupants leave the vehicle, lowering
control will occur for a short while after the engine has been stopped.
■The rear height control air suspension failure warning
●If a malfunction occurs in the rear height control air suspension, N mode is automati-
cally selected. However, the system may not switch to N mode depending on the loca-
tion of the malfunction.
●The warning message is displayed on the mult i-information display, and the rear height
control air suspension cannot be activated until the malfunction is corrected.
Stop the engine and start it again. If the wa rning message turns off, the system is operat-
ing correctly. If the warning message continues to be displayed, have your vehicle
inspected by your Lexus dealer as soon as possible.

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GX460_OM_OM60Q09U_(U)4-5. Using the driving support systems
CAUTION
■The rear height control air suspension must be turned off
Be sure to observe the following precautions. Otherwise, the automatic leveling func-
tion may cause vehicle height to change, an
d you may catch part of your body in the
vehicle, resulting in an accident:
●When jacking up the vehicle, installing tire chains or tying the vehicle with chains/
wires for transportation via flatbed truck, tu rn off the rear height control air suspen-
sion and stop the engine.
●When the vehicle must be towed or disconnect ing a trailer, put the vehicle height in N
mode and turn off the rear he ight control air suspension.
●When the vehicle is stuck, turn off the rear height control air suspension.
■Selecting the correct height mode
●HI mode should only be used when drivin g on rough roads, for example when driving
off-road.
Because the vehicle’s center of gravity will become higher when in the mode, the
vehicle may become unstable when turnin g abruptly, resulting in an accident.
●Do not select HI mode when loading cargo on the roof luggage carrier.
Because the vehicle’s center of gravity will become higher when in the mode, the
vehicle may become unstable when turnin g abruptly, resulting in an accident.
●Before lowering vehicle height, check that there is no one under the vehicle.
NOTICE
■Be careful in any place where overhead space is limited
The vehicle height will rise when a higher mode is selected or cargo is unloaded. This
may cause damage to the vehicle.
■Do not select LO mode when driving on bumpy roads
If the underbody of the vehicle touches a rugged road surface, the vehicle may be
damaged.
■Changing vehicle height
Do not change vehicle height frequently.
The compressor may overhe at and stop operation.
■When on the extremely uneven roads with rocks
Sometimes the vehicle height is not adjusted because it is judged as uneven road driv-
ing.

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GX460_OM_OM60Q09U_(U)4-5. Using the driving support systems
■When the four-wheel drive control switch can be operated
●The engine switch is in IGNITION ON mode.
●The shift lever is in the N position.
●The vehicle is stopped completely.
■The low speed four-wheel drive indicator
●The indicator blinks while sw
itching between H4 and L4.
●If the low speed four-wheel drive indicator continues to blink when you operate the
four-wheel drive control switch to the H4 or L4 position, stop the vehicle completely,
shift the shift lever securely into N and then operate the switch again.
●If the shift lever is moved before the low speed four-wheel drive indicator turns on/off,
the transfer mode may not be shifted completely. The transfer mode disengages both
the front and rear drive shafts from the powertrain and allows the vehicle to move
regardless of the shift position. (At this time , the indicator blinks and the buzzer sounds.)
Therefore, the vehicle is free to roll even if the shift lever is in P. You or someone else
could be seriously injured. You must comple te the shifting of the transfer mode and
confirm that the indicator has turned off (H4) or turned on (L4).
●If the engine coolant temperature is too low, the four-wheel drive control system may
not be able to shift. When the engine is warmer operate the switch again.
If the indicator continue to blink even if doing so, have the vehicle inspected by your
Lexus dealer as soon as possible. There may be a trouble in the four-wheel drive system.
■When the transfer mode is switched to L4
Vehicles without Multi-terrain Select:
VSC is automatically turned off. (T he VSC OFF indicator will come on.)
Vehicles with Multi-terrain Select:
VSC and TRAC/Active TRAC are automatically turned off. (The VSC OFF indicator will
come on and the “TRAC OFF” will be sh own on the multi-information display.)
■When the center differential lock/unlock switch can be operated
The engine switch is in IGNITION ON mode.
■The center differential lock indicator
●The indicator blinks while locking/unlocking the center differential.
●If the center differential lock indicator b links and the buzzer sounds when the center
differential is locked, stop the slipping or spinning and push the switch again.
If the indicator continue to blink even if doing so, have the vehicle inspected by your
Lexus dealer as soon as possible. There may be a trouble in the four-wheel drive system.

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Driving
●LO (low mode)
Effective when traveling on rocks, or descending a slope of mogul and rub-
ble.
*
●MED (medium mode)
Effective when ascend ing a slope of mogul.
*
●HI (high mode)
Effective when ascending a slope of mo gul and rubble, or traveling on snow,
dirt, mud, sand, gravel, grass etc.
*
The position between low and medium modes and the position between medium
and high modes can also be selected.
*: Depending on the road surface, may not be the most effective.
■The Crawl Control can be operated when
●The shift lever is in any gear other than P or N.
●The four-wheel drive control switch is in L4.
●The driver’s door is closed.
■Automatic system cancelation
In the following situations, the system is canceled automatically:
At that time, the buzzer will sound, the slip indicator turns off, and the Crawl Control indi-
cator flashes.
A notification will be displa yed on the multi-information display for several seconds.
( → P. 528)
●When the shift lever is moved to P or N.
●When the four-wheel drive control switch is in H4.
●When the driver’s door is opened.
When turning off Crawl Control while travelin g, stop the vehicle before the Crawl Con-
trol indicator turns off, or drive extremely carefully.
■Function limit
●In the following situations, you will be able to use brake control to drive downhill at a
fixed low speed, but you will be unable to use engine control to drive uphill at a fixed low
speed.
• When the driving mode is set to second start mode.
• When the vehicle speed is higher than 6 mph (10 km/h).
●When the vehicle speed is higher than 15 mph (25 km/h), engine control and brake
control will stop temporarily. At that time, the Crawl Control indicator flashes.
Speed modes

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GX460_OM_OM60Q09U_(U)4-5. Using the driving support systems
■When the Crawl Control system
is operated continuously
This may cause the brake actuator to overheat . In this case, the Crawl Control system will
stop operating, a buzzer will sound, the Crawl Control indicator will turn off after flashing
and the “TRAC OFF” will be show n on the multi-information display. In this case, quickly
stop the vehicle in a safe place and give the actuator adequate time to cool off. Refrain
from using the system until the message goes off. (The vehicle can be driven normally
during this time.)
■If the automatic transmission system overheats
The system will cease operation, a buzzer w ill sound and a warning message will be dis-
played to alert the driver. Stop the vehicle in a safe place until the warning message turns
off. ( →P. 533)
■Sounds and vibrations caused by the Crawl 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 soun d does not indicate that a malfunction has
occurred in Crawl Control system.
●Either of the following conditions may occu r when the Crawl Control system is operat-
ing. 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 afte r the vehicle comes to a stop.
■If the slip indicator comes on...
It may indicate a malfunction in the system. Cons ult your Lexus dealer.
CAUTION
■When using Crawl Control
Do not rely solely on the Crawl Control. This function does not extend the vehicle’s
performance limitations. Always thoroughly check the road conditions, and drive
safely.
■These conditions may cause the system not to operate properly
When driving on the following surfaces, the sy stem may not be able to maintain a fixed
low speed, which may re sult in an accident:
●Extremely steep inclines.
●Extremely uneven surfaces.
●Snow-covered roads, or other slippery surfaces.

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GX460_OM_OM60Q09U_(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 OF F” will be shown on the multi-information
display. Refrain from using th e system until the downhill assi st control system indicator
stays on and the message goes of f. (The vehicle 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 soun d does not indicate that a malfunction has
occurred in downhill assist control system.
●Either of the following conditions may occur when the do wnhill 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 afte r 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 indicator 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