Lexus GX470 2008 Owner's Manual

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2-5. Driving information
Trailer towing
Your vehicle is designed primarily as a passenger-and-load carrying vehi-
cle. Towing a trailer will have an adverse effect on handling, performance,
braking, durability, and fuel consumption. For your safety and the safety of
others, do not overload the vehicle or trailer.
Lexus warranties do not apply to damage or malfunction caused by towing
a trailer for commercial purposes.
■ Weight limits
Confirm that the total trailer weight, gross vehicle weight, gross axle
weight and trailer tongue load are all within the limits.
■ Gross vehicle weight
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, pas-
sengers, luggage, hitch and trailer tongue load. Also included is the
weight of any special equipment installed on your vehicle.
■ Gross axle weight
The load on either the front or rear axle resulting from distribution of
the gross vehicle weight on both axles must not exceed the Gross
Axle Weight Rating (GAWR) listed on the Certification Label.
Certification Label

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2-5. Driving information
2
When driving
Towing a trailerContact your Lexus dealer for further information about additional
requirements such as a towing kits, etc.
Hitch and tow hitch receiver■ Hitch
Trailer hitch assemblies have different weight capacities established by
the hitch manufacturer. Even though the vehicle may be rated for tow-
ing a higher weight, the operator must never exceed the maximum
weight rating specified for the trailer hitch.
■Trailer tongue load
The trailer cargo load should be distributed so that the tongue load
is 9 to 11% for weight carrying hitch or 15% for weight distributing
hitch of the total trailer weight, not exceeding the following.
Weight carrying hitch: 650 lb. (294 kg)
Weight distributing hitch: 975 lb. (442 kg)
(Tongue load/Total trailer weight x 100 = 9 to 11% or 15%)
The total trailer weight and tongue load can be measured with plat-
form scales found at a highway weighing stations, building supply
companies, trucking companies, junk yards, etc.
Total trailer weight
Tongue load

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2-5. Driving information
■Tow hitch receiver
A tow hitch receiver installed
under the rear bumper is rated for
weight that does not exceed the
vehicle’s total towing weight.
Selecting trailer ball
Use the correct trailer ball for your application. Trailer ball load rating
Matches or exceeds the gross
trailer weight rating of the trailer.
Ball diameter
Matches the size of the trailer cou-
pler. Most couplers are stamped
with the required trailer ball size.
Shank length
Protrudes beyond the bottom of
the lock washer and nut at least 2
threads.
Shank diameter
Matches the ball mount hole diam-
eter size.

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2-5. Driving information
2
When driving
Connecting trailer lightsUse the wire harness stored in the rear end underbody.
■When connecting and disconnecting a trailer Connecting
Set the rear height control air suspension to “LO” mode.
Turn off the engine switch or the rear height control air suspension.
Connect the trailer.
Turn on the switch that was turned off on STEP 2.
Set the rear height control air suspension to “N” mode.
Disconnecting
Set the rear height control air suspension to “LO” mode.
Turn off the engine switch or the rear height control air suspension.
Set the supporting leg of the trailer on the ground and raise the hitch by
4 in. (100 mm).
Turn on the switch that was turned off on STEP 2.
Wait until vehicle height is stabilized.
Make sure the hitch is disconnected. If the hitch does not disconnect, raise
the hitch higher and repeat steps 2 through 5.
Move the vehicle forward in the “LO” mode where the hitch does not
touch anything in the “N” mode.
Set the rear height control air suspension in the “N” mode.
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2-5. Driving information
■Before towing
Check that the following conditions are met:
●The vehicle’s tires are properly inflated. (→P. 4 1 9 )
●Trailer tires are inflated according to the trailer manufacturer’s recommenda-
tion.
●All trailer lights work.
●All lights work each time you connect them.
●The trailer ball is set up at the proper height for the coupler on the trailer.
●The vehicle remains level when a loaded or unloaded trailer is hitched. Do not
drive if the vehicle is not level, and check for improper tongue load, overloading,
worn suspension, or other possible causes.
●The trailer cargo is securely loaded.
●The rear view mirrors conform to all applicable federal, state/provincial or local
regulations. If they do not, install rear view mirrors appropriate for towing pur-
poses.
■Break-in schedule
Lexus recommends that you do not use a new vehicle or a vehicle with any new
power train components (engine, transmission, differential, wheel bearings, etc.) to
tow a trailer for the first 500 miles (800 km) of driving.
■Maintenance
●If you tow a trailer, your vehicle will require more frequent maintenance due to
the additional load. (See “Warranty and Services Guide/Owner’s Manual Sup-
plement/Scheduled Maintenance”.)
●Retighten the fixing bolts of the towing ball and bracket after approximately
600 miles (1000 km) of trailer towing.

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2-5. Driving information
2
When driving
CAUTION
■To avoid accident or injury
●The total trailer weight (trailer weight plus the weight of cargo) must not exceed
6500 lb. (2948 kg).
●If a trailer and cargo weight over 2000 lb. (907 kg), use a sway control device
with sufficient capacity.
●The gross combined weight (sum of your vehicle weight plus its load and the total
trailer weight) must not exceed 12000 lb. (5443 kg).
●Do not exceed the trailer hitch assembly weight, gross vehicle weight, gross axle
weight and trailer tongue load capacities.
●Never load more weight in the back than in the front of the trailer. About 60% of
the load should be in the front half of the trailer, and the remaining 40% in the
rear.
●Set the vehicle height to the “LO” mode and turn off the rear height control air
suspension to prevent the vehicle height from automatically changing.
●The tow hitch receiver installed on your vehicle must never be used on another
vehicle
■Hitches
●If you wish to install a trailer hitch, contact your Lexus dealer.
●Use only a hitch that conforms to the total trailer weight requirement.
●Follow the directions supplied by the hitch manufacturer.
●Lubricate the hitch ball with a light coat of grease.
●Remove the trailer hitch whenever you are not towing a trailer. After removing
the hitch, seal any mounting hole in the vehicle body to prevent entry of any sub-
stances into the vehicle.
■When towing a trailer
●If the total trailer weight exceeds 1000 lb. (453 kg), trailer brakes are required.
●Never tap into your vehicle’s hydraulic system, as this will lower the vehicle’s brak-
ing 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
danger of the trailer wandering into another lane.

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2-5. Driving information
NOTICE
■When installing a trailer hitch
●Use only the position recommended by your Lexus dealer. Do not install the
trailer hitch on the bumper; this may cause body damage.
●Do not use axle-mounted hitches, as they can cause damage to the axle housing,
wheel bearings, wheels or tires.
■Brakes
Lexus recommends trailers with brakes that conform to all applicable federal and
state/provincial regulations.
■Safety chain
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 the case that it
becomes damaged or separated. For the correct safety chain installation proce-
dure, ask your Lexus dealer.
■Do not directly splice trailer lights
Directly splicing trailer lights may damage your vehicle’s electrical system and
cause a malfunction.

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2-5. Driving information
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When driving
Trailer towing tipsYour vehicle will handle differently when towing a trailer. The 3 main
causes of vehicle-trailer accidents are driver error, excessive speed and
improper trailer loading. Keep the following in mind when towing.
● Before starting out, check the trailer lights and the vehicle-trailer con-
nections. Recheck after driving a short distance.
● Practice turning, stopping and rever sing with the trailer attached in an
area away from traffic until you become accustomed to the feel of the
vehicle.
● Reversing with a trailer attached is difficult and requires practice Grip
the bottom of the steering wheel 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 right. (This is generally opposite to reversing without a trailer
attached.) Avoid sharp or prolon ged turning. Have someone guide
you when reversing to reduce the risk of an accident.
● As stopping distance is increased when towing a trailer, vehicle-to-
vehicle distance should be increased. For each 10 mph (16 km/h) of
speed, allow at least one vehicle and trailer length.
● 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, and slow down before making
turns.

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2-5. Driving information
●Note that when making a turn, the trailer wheels will be closer than the
vehicle wheels to the inside of the turn. Compensate by making a
larger than normal turning radius.
● Crosswinds and rough roads will adversely affect handling of your
vehicle and trailer, causing sway. Periodically check the rear to prepare
for being passed by large trucks or buses, which may cause your vehi-
cle and trailer to sway. If swaying occurs, firmly grip the steering wheel,
reduce speed immediately but gradually, and steer straight ahead.
Never increase speed. If you make no extreme correction with the
steering or brakes, your vehicle and trailer will stabilize.
● Take care 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 shift range position
must be in “4”.
● Due to the added load of the trailer, your vehicle’s engine may overheat
on hot days (at temperatures over 85°F [30°C] when driving up a
long or steep grade. 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. (
→P. 4 0 8 )

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2-5. Driving information
2
When driving
●Always place wheel blocks under both the vehicle and the trailer
wheels when parking. Apply the parking brake firmly, and put the
transmission in “P”. Avoid parking on a slope, but if unavoidable, do so
only after performing the following:
Apply the brakes and keep them applied.
Have someone place wheel blocks under both the vehicle and
trailer wheels.
When the wheel blocks are in place, release the brakes slowly
until the blocks absorb the load.
Apply the parking brake firmly.
Shift into “P” and turn off the engine.
● When restarting after parking on a slope:
With the transmission in the “P” position, start the engine. Be sure
to keep the brake pedal pressed.
Shift into “3”, “2”, “L”, or “R” position (if reversing).
Release the parking brake and brake pedal, and slowly pull or
back away from the wheel blocks. Stop and apply the brakes.
Have someone retrieve the blocks.
CAUTION
■To avoid an accident
●Do not exceed 45 mph (72 km/h) or the posted towing speed limit, whichever is
lower. A instability (swaying) of the towing vehicle-trailer combination increases
as speed increases, exceeding 45 mph (72 km/h) 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 applying the brakes too fre-
quently.
This could cause the brakes to overheat and result in reduced braking efficiency.
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