2004 Lexus GX470 transmission

STARTING AND DRIVING
408
DOWNHILL ASSIST CONTROL
SYSTEM
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 four-wheel drive control lever in the Lº position,
push the DACº 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 off-road surfaces on which sliding can
easily occur, such as extremely steep slopes or icy or
muddy roads.
Turning on the system
1. Shift the four-wheel drive control lever to the Lº
position.
The system will not operate if the four-wheel drive control lever
is in the Hº position.
2. In order to make full use of the engine brake, putting the
transmission in Lº or 2º is recommended.
The system will operate even if the transmission selector lever
is in Dº, 4º, 3º or Nº. However, when it is in Lº or 2º the
engine brake can also be utilized enabling the system to
operate more effectively.
3. Push the DACº 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 Nº or four-wheel drive
control lever may be in the Hº position.

STARTING AND DRIVING
411
HILL-ST ART ASSIST CONTROL
SYSTEM
The hill-start assist control system assists you in starting
to move up a steep or slippery hill. When you start to move
up the hill slope, the system helps to prevent the vehicle
from rolling backward in the interval while you move your
foot from the brake pedal to the accelerator pedal.
CAUTION
Do not rely excessively on the hill-start assist control
system. The vehicle may not be able to start
smoothly on road surfaces or off-road surfaces such
as extremely steep slopes or icy roads, on which
sliding can occur very easily.
Do not use the hill-start assist control system to stop
the vehicle. This system is not designed as a function
for stopping the vehicle on a uphill slope.
The hill-start assist control system will operate for 5
seconds maximally when all of the following conditions
apply.
When the transmission is in any of positions Dº, 4º,
3º, 2º or Lº
When the brake pedal is not depressed
The system is designed to operate when the vehicle is starting
on an uphill slope; therefore, if the transmission is in Pº or Nº
it will not operate. It will not operate either if the vehicle starts
to move in reverse on a slope with the transmission in the Rº.

Slip indicator light
When the hill-start assist control system is operating, the slip
indicator light flashes and an alarm sounds intermittently. At
the same time, the stop lamps and high mounted stoplight are
lit.

DRIVING TIPS
432
OPERATION IN FOREIGN
COUNTRIES
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 such as a tire burst.
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 place the transmission in Pº. 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
437
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 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
maintenance information, refer to the Owner's
Manual Supplement/Scheduled Maintenanceº.

DRIVING TIPS
439 Use a washer fluid containing an antifreeze solution.
This product is available at your Lexus dealer and most auto
parts stores. Follow the manufacturer's directions for how
much to mix with water.
NOTICE
Do not use engine antifreeze or any other substitute
because it may damage your vehicle's paint.
Do not use your parking brake when there is a possibility
it could freeze.
When parking, put the transmission into Pº and block the front
wheels. Do not use the parking brake, or snow or water
accumulated in and around the parking brake mechanism may
freeze the parking brake, making it hard to release.Keep ice and snow from accumulating under the fenders.
Ice and snow built up under your fenders can make steering
difficult. During bad winter driving, stop and check under the
fenders occasionally.
Depending on where you are driving, we recommend you
carry some emergency equipment.
Some of the things you might put in the vehicle are tire chains,
window scraper, bag of sand or salt, flares, small shovel,
jumper cables, etc.

DRIVING TIPS
450
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.
Break-in 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
Maintenanceº.
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 LOº (low)
mode. Turn the ignition switch off or push the HEIGHT
CONTROL OFFº 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
OFFº switch to turn on the rear height control air suspension.
Select the Nº (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 LOº (low)
mode. (Make sure the vehicle height is in the LOº (low) mode
by pushing the height select switch on the º side.)
2. Turn the ignition switch off or push the HEIGHT CONTROL
OFFº 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
OFFº switch to turn on the rear height control air suspension.
5. Wait for about 20 seconds until the rear vehicle height is
lowered by the automatic leveling function.
6. Make sure the hitch is disconnected. If not, raise the hitch
higher and repeat steps 2 through 5.

DRIVING TIPS
452Remember that when making a turn, the trailer wheels will
be closer than the vehicle wheels to the inside of the turn.
Therefore, compensate for this by making a larger than
normal turning radius with your vehicle.
Crosswinds and rough roads will adversely affect handling
of your vehicle and trailer, causing sway. Pay attention to
the rear from time to time to prepare yourself for being
passed by large trucks or buses, which may cause your
vehicle and trailer to sway. If swaying happens, firmly grip
the steering wheel and reduce speed immediately but
gradually. Never increase speed. If it is necessary to
reduce speed, brake slowly. Steer straight ahead. If you
make no extreme correction with the steering or brakes,
your vehicle and trailer will stabilize.
Be careful when passing other vehicles. Passing requires
considerable distance. After passing a vehicle, do not forget
the length of your trailer and be sure you have plenty of room
before changing lanes.
In order to maintain efficient engine braking and electrical
charging performance, do not use overdrive. Transmission
must be 4º position.
Because of the added load of the trailer, your vehicle's
engine may overheat on hot days (at temperatures over
30C [85F]) when going up a long or steep grade with a
trailer. If the engine coolant temperature gauge indicates
overheating, immediately turn off the air conditioning (if in
use), pull your vehicle off the road and stop in a safe spot.
See If your vehicle overheatsº on page 467.Always place wheel blocks under both the vehicle and trailer
wheels when parking. Apply the parking brake firmly. Put
the transmission in Pº. Avoid parking on a slope with a
trailer, but if it cannot be avoided, do so only after performing
the following:
1. Apply the brakes and keep them applied.
2. Have someone place wheel blocks under both the vehicle
and trailer wheels.
3. When the wheel blocks are in place, release your brakes
slowly until the blocks absorb the load.
4. Apply the parking brake firmly.
5. Shift into Pº and turn off the engine.

DRIVING TIPS
453 When restarting out after parking on a slope:
1. With the transmission in Pº position, start the engine. Be
sure to keep the brake pedal depressed.
2. Shift into the 3º, 2º, Lº or Rº position.
3. Release the parking brake and brake pedal and slowly pull
or back away from the wheel blocks. Stop and apply your
brakes.
4. Have someone retrieve the blocks.
CAUTION
Do not exceed 72 km/h (45 mph) or the posted towing
speed limit, whichever is lower. Because instability
(swaying) of a towing vehicle-trailer combination
usually increases as the speed increases, exceeding
72 km/h (45 mph) may cause loss of control.
Slow down and downshift before descending steep
or long downhill grades. Do not make sudden
downshifts.
Avoid holding the brake pedal down too long or too
frequently. This could cause the brakes to overheat
and result in reduced braking efficiency.
HOW TO SAVE FUEL AND MAKE
YOUR VEHICLE LAST LONGER
Improving fuel economy is easy Ð just take it easy. It will help
make your vehicle last longer, too. Here are some specific tips
on how to save money on both fuel and repairs:
Keep your tires inflated at the correct pressure. Check
the pressure every two weeks, or at least once a month.
Underinflation causes tire wear and wastes fuel.
Do not carry unneeded weight in your vehicle. Excess
weight puts a heavier load on the engine, causing greater
fuel consumption.
Avoid lengthy warm-up idling. Once the engine is
running smoothly, begin driving Ð but gently. Remember,
however, that on cold winter days this may take a little
longer.
Always keep the automatic transmission selector lever
in the Dº position when engine braking is not required.
Driving with the overdrive off will reduce the fuel economy.
(For details, see Automatic transmissionº on page 376.)
Accelerate slowly and smoothly. Avoid jackrabbit starts.
Avoid long engine idling. If you have a long wait and you
are not in traffic, it is better to turn off the engine and start
again later.
Avoid engine over-revving. Use a gear position suitable
for the road on which you are traveling.