2003 Lexus GX470 Towing

SECTION 3 – 2
338
STARTING AND DRIVING
Driving tips
Off−road vehicle precautions 339
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Break−in period 340
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Operation in foreign countries 341
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Tips for driving in various conditions 341
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Off −road driving precautions 343
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Winter driving tips 345
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Dinghy towing 346
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Trailer towing 347
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How to save fuel and make your vehicle
last longer 356
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DRIVING TIPS
346Depending 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.
DINGHY TOWING
Your vehicle is not designed to be dinghy towed (with four
wheels on the ground) behind a motorhome.
NOTICE
Do not tow your vehicle with four wheels on the ground.
This may cause serious damage to your vehicle.

DRIVING TIPS
347
TRAILER TOWING
Your vehicle is designed primarily as a passenger−and−load
carrying vehicle. T owing a trailer will have an adverse ef fect on
handling, performance, braking, durability and driving
economy (fuel consumption, etc.). Y our safety and satisfaction
depend on the proper use of correct equipment and cautious
driving habits. For your safety and the safety of others, you
must not overload your vehicle or trailer. Lexus warranties do
not apply to damage or malfunction caused by towing a trailer
for commercial purposes. Ask your local Lexus dealer for
further details before towing.
CAUTION
When disconnecting a trailer, put the vehicle height in
the “LO” (low) mode and push the “HEIGHT CONTROL
OFF” switch to turn off the rear height control air
suspension. Otherwise, the vehicle height may be
changed in the automatic leveling function, resulting in
accident. For details see “Rear height control air
suspension” on page 315.
Weight limits
Before towing, make sure the total trailer weight, gross
vehicle weight, gross axle weight and trailer tongue load
are all within the limits.
The total trailer weight and tongue load can be measured with
platform scales found at a highway weighing station, building
supply company, trucking company, junk yard, etc.
 Certification label
CAUTION
 The maximum gross trailer weight (trailer weight plus
cargo weight) must never exceed 2268 kg (5000 lb.)
for vehicle with equipped. If towing a trailer and
cargo weighing over 907 kg (2000 lb.), it is necessary
to use a sway control device with sufficient capacity.
The combination of the gross trailer weight added to
the total weight of the vehicle, occupants and vehicle
cargo must never exceed a total of 4764 kg (10500 lb.).
Exceeding the maximum weight of the trailer, the
vehicle, or the vehicle and trailer combination, can
cause an accident resulting in serious personal
injuries.

Tongue load
Total trailer weight x 100= 9 to 11%
DRIVING TIPS
348

Trailer hitch assemblies have different weight
capacities established by the hitch manufacturer.
Even though the vehicle may be physically capable of
towing a higher weight, the operator must determine
the maximum weight rating of the particular hitch
assembly and never exceed the maximum weight
rating specified for the trailer hitch. Exceeding the
maximum weight rating set by the trailer hitch
manufacturer can cause an accident resulting in
serious personal injuries.
 The gross vehicle weight must not exceed the Gross
Vehicle Weight Rating (GVWR) indicated on the
Certification Label. The gross vehicle weight is the
sum weight of the unloaded vehicle, driver,
passengers, luggage, hitch and trailer tongue load.
It also includes the weight of any special equipment
installed on your vehicle.
 The load on either the front or rear axle resulting from
distribution of the gross vehicle weight on both axles
must not exceed the front and rear Gross Axle W eight
Ratings (GAWR) listed on the Certification Label.
 Total trailer weight  Tongue load
 The trailer cargo load should be distributed so that
the tongue load is 9 to 11% of the total trailer weight,
not exceeding the maximum of 226 kg (500 lb.).
 Never load the trailer with more weight in the back
than in the front. About 60 % of the trailer load should
be in the front half of the trailer and the remaining 40%
in the rear.

DRIVING TIPS
349
Tow hitch receiver (on some models)
The tow hitch receiver is installed under the rear bumper.
CAUTION
A tow hitch receiver is rated for weight carrying towing
only up to 2268 kg (5000 lbs.) Only use this tow hitch
receiver on your vehicle. Do not use this tow hitch
receiver on any other vehicle.
Hitches
Use only weight carrying hitch hardware designed for the
total trailer weight with the factory installed hitch.
 If you wish to install an aftermarket hitch, the hitch must be
bolted securely to the vehicle frame and installed according
to the hitch manufactures’ instructions.
 The hitch ball and king pin should have a light coat of grease.
 Lexus recommends the ball mount assembly be removed
when not towing to prevent injury and to prevent damage in
the event of a rear end collision. After removing the ball
mount assembly, install the grommet to the hitch to prevent
entry of dirt and mud.
Trailer ball
Follow these easy steps to properly determine the correct
trailer ball for your application:
1. Determine the correct trailer ball size for the trailer coupler.
Most couplers are stamped with the required trailer ball size.
The sizes you’ll most likely find stamped on the coupler are:
Trailer Class
Typical Trailer Ball Size
III 2−5/16 in.
II 2 in.
I1 −7/8 in.
2. Select the appropriate trailer ball to match or exceed the
gross trailer weight rating of the trailer. The trailer ball load
rating should be printed on the top of the ball.

DRIVING TIPS
351
Brakes and safety chains
Lexus recommends trailers with brakes that conform to
any applicable federal and state/provincial regulations.
 A safety chain must always be used between the towing
vehicle and the trailer. Leave sufficient slack in the
chain for turns. The chain should cross under the
trailer tongue to prevent the tongue from dropping to
the ground in case it becomes damaged or separated.
For correct safety chain procedures, consult your
Lexus dealer.
CAUTION
If the total trailer weight exceeds 453 kg (1000 lb.),
trailer brakes are required.
 Never tap into your vehicle’s hydraulic system as it
will lower its braking effectiveness.
 Never tow a trailer without using a safety chain
securely attached to both the trailer and the vehicle.
If damage occurs to the coupling unit or hitch ball,
there is possible danger of the trailer wandering over
into another lane.
Service connector for towing brake controller
Your vehicle is equipped with a service connector for the
towing brake controller as shown. Link the connector to the
towing brake controller via the sub wire harness stored in the
glove box. The detailed explanation of the sub wire harness
circuit is packed together with the sub wire harness. Be sure
to position the towing brake controller where it does not prevent
the driver from operating the pedal. Lexus recommends that
the sub wire harness be stored in the glove box when it is not
in use.

DRIVING TIPS
353
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.
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.
7. Move the vehicle forward in the “LO” (low) mode where the
hitch does not touch anything in the “N” (normal) mode.
8. Put the rear height control air suspension in the “N” (normal)
mode.

DRIVING TIPS
354
Pretowing safety check
Check that your vehicle remains level when a loaded or
unloaded trailer is hitched. Do not drive if the vehicle has an
abnormal nose −up or nose− down condition, and check for
improper tongue load, overload, worn suspension or other
possible causes.
 Make sure the trailer cargo is securely loaded so that it
cannot shift.
 Check that your rear view mirrors conform to any federal,
state/provincial or local regulations. If they do not, install
required rear view mirrors appropriate for towing purposes.
Trailer towing tips
When towing a trailer, your vehicle will handle differently
than when not towing. The three main causes of
vehicletrailer accidents are driver error, excessive speed
and improper trailer loading. Keep these in mind when
towing:
 Before starting out, check the operation of the lights and all
vehicle −trailer connections. After driving a short distance,
stop and recheck the lights and connections. Practice
turning, stopping and backing with a trailer in an area away
from traffic until you learn the feel. 
Backing with a trailer is difficult and requires practice. Grip
the bottom of the steering whe el and move your hand to the
left to move the trailer to the left. Move your hand to the right
to move the trailer to the right. (This procedure is generally
opposite to that when backing without a trailer.) Also, just
turn the steering wheel a little at a time, avoiding sharp or
prolonged turning. Have someone guide you when backing
to reduce the risk of an accident.
 Because stopping distance may be increased,
vehicle −to−vehicle distance should be increased when
towing a trailer. For each 16 km/h (10 mph) of speed, allow
at least one vehicle and trailer length between you and the
vehicle ahead. Avoid sudden braking as you may skid,
resulting in jackknifing and loss of control. This is especially
true on wet or slippery surfaces.
 Avoid jerky starts or sudden acceleration.
 Avoid jerky steering and sharp turns. The trailer could hit
your vehicle in a tight turn. Slow down before making a turn
to avoid the need of sudden braking.
 Remember 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.