Lexus GX470 2005 Engine / LEXUS 2005 GX470 OWNER'S MANUAL (OM60B11U)

DRIVING TIPS
470
TRAILER TOWING
Your vehicle is designed primarily as a passenger±and±load
carrying vehicle. Towing a trailer will have an adverse ef fect on
handling, performance, braking, durability and driving
economy (fuel consumption, etc.). Your 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 ªLOº (low) mode and push the ªHEIGHT CONTROL
OFFº 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 ªRear height control air
suspensionº on page 422.
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

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471

Weight distributing hitch receiver
CAUTION
The maximum gross trailer weight (trailer weight plus
cargo weight) must never exceed 2948 kg (6500 lb.)
for vehicle with equipped.
If towing a trailer and cargo weighing over 907 kg
(2000 lb.), Lexus recommends 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 5443 kg (12000 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.
 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.

Tongue load
Total trailer weight

100 = 10%
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472
 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 10% of the total trailer weight, not
exceeding the maximum of 294 kg (650 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.

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473
Hitches
If you wish to install a trailer hitch, you should consult with
your Lexus dealer.
 Use only a hitch recommended by the hitch manufacture
and the one which conforms to the total trailer weight
requirement.
 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.

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474
NOTICE
Do not use axle±mounted hitches as they can causedamage to the axle housing, wheel bearings, wheels ortires. Also, never install a hitch which may interfere with
the normal function of an Energy Absorbing Bumper.
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 in.
II 2 in.
I 1 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.

1Trailer ball load rating
2Ball diameter
3Shank length
4Shank diameter

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475
3. When mounted in the ball mount, the threaded ball shank
must protrude beyond the bottom of the lock washer and nut
at least 2 threads. The trailer ball shank must be matched to
the ball mount hole diameter size.
NOTICE
Only use a ball mount attachment specified for the
Lexus GX470.

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476
Matching trailer ball height to trailer coupler
height
No matter which class of tow hitch applies, for a safe trailer
hookup, the trailer ball setup on must be the proper height for
the coupler on the trailer.
32PY007

1Coupler2Trailer ball

DRIVING TIPS
477
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
478
Tires
Ensure that your vehicle's tires are properly inflated. Adjust
the tire inflation pressure to the recommended cold tire
inflation pressure indicated below.
Tire inflation pressure: 220 kPa (2.2 kgf/cm
2 or bar, 32 psi)
 The trailer tires should be inflated to the pressure
recommended by the trailer manufacturer in respect to the
total trailer weight.
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 ªOwner's Manual Supplement/Scheduled
Maintenanceº.
 Retighten all fixing bolts of the towing ball and bracket after
approximately 1000 km (600 miles) of trailer driving.

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479
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 ªLOº (low)
mode. Turn the ignition switch off or push the ªHEIGHT
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 ªHEIGHT CONTROL
OFFº switch to turn on the rear height control air suspension.
Select the ªNº (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 ªLOº (low)
mode. (Make sure the vehicle height is in the ªLOº (low) mode
by pushing the height select switch on the ª º side.)
2. Turn the ignition switch off or push the ªHEIGHT 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 ªHEIGHT 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.
7. Move the vehicle forward in the ªLOº (low) mode where the
hitch does not touch anything in the ªNº (normal) mode.
8. Put the rear height control air suspension in the ªNº (normal)
mode.
Pre±towing safety check

Check that your vehicle remains level when a loaded or
unloaded tra iler 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.