LEXUS RX 450HL (2019 year). Instruction - part 14

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Contact your Lexus dealer for further information about additional requirements
such as a towing kit, etc.

Trailer towing (vehicles with towing package)

Your vehicle is designed primarily as a passenger-and-load-carrying vehicle.
Towing a trailer can have an adverse impact on handling, performance, brak-
ing, durability, and fuel consumption. For your safety and the safety of others,
you must not overload your vehicle or trailer. You must also ensure that you
are using appropriate towing equipment, that the towing equipment has been
installed correctly and used properly, and that you employ the requisite driv-
ing habits.
Vehicle-trailer stability and braking performance are affected by trailer sta-
bility, brake performance and setting, trailer brakes, the hitch and hitch sys-
tems (if equipped).
To tow a trailer safely, use extreme care and drive the vehicle in accordance
with your trailer’s characteristics and operating conditions.
Lexus warranties do not apply to damage or malfunction caused by towing a
trailer for commercial purposes.

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GCWR (Gross Combination Weight Rating)
The maximum allowable gross com-
bination weight. The gross combina-
tion weight is the sum of the total
vehicle weight (including the occu-
pants, cargo and any optional equip-
ment installed on the vehicle) and
the weight of the trailer being towed
(including the cargo in the trailer).

■

GVWR (Gross Vehicle Weight Rating)
The maximum allowable gross vehi-
cle weight. The gross vehicle weight
is the total weight of the vehicle.
When towing a trailer, it is the sum of
the vehicle weight (including the
occupants, cargo and any optional
equipment installed on the vehicle)
and the tongue weight.

■

GAWR (Gross Axle Weight Rating)
The maximum allowable gross axle
weight. The gross axle weight is the
load placed on each axle (front and
rear).

Towing related terms

Front GAWR

Rear GAWR

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TWR (Trailer Weight Rating)
The maximum allowable gross trailer
weight. The gross trailer weight is
the sum of the trailer weight and the
weight of the cargo in the trailer.
TWR is calculated assuming base
vehicle with one driver, one front
passenger, towing package (if avail-
able), hitch and hitch systems (if
required).

Additional optional equipment, passengers and cargo in the vehicle will reduce the

trailer weight rating so as not to exceed GCWR, GVWR and GAWR.
If the gross trailer weight exceeds 3000 lb. (1360 kg), it is recommended to use a

trailer with 2 or more axles.

■

Unbraked TWR (Unbraked Trailer Weight Rating)
The trailer weight rating for towing a
trailer without a trailer service brake
system.

■

Tongue Weight
The load placed on the trailer hitch
ball. (

P. 228)

(With brakes)

(Without brakes)

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The gross trailer weight must never exceed 3500 lb. (1585 kg).

●

The gross combination weight must never exceed 9500 lb. (4309 kg). 

●

The gross vehicle weight must never
exceed the GVWR indicated on the
Certification Label.

●

The gross axle weight on each axle
must never exceed the GAWR indi-
cated on the Certification Label.

●

If the gross trailer weight is over the unbraked TWR, trailer service brakes are
required.

●

If the gross trailer weight is over 2000 lb. (907 kg), a sway control device with
sufficient capacity is required.

Confirm that the gross trailer weight, gross combination weight, gross vehicle
weight, gross axle weight and tongue weight are all within the limits.

■

GCWR

*

9500 lb. (4309 kg)

■

TWR

*

3500 lb. (1585 kg)

■

Unbraked TWR

*

1000 lb. (453 kg)

*

: These models meet the tow-vehicle trailering requirement of SAE International per

SAE J2807.

Weight limits

GCWR, TWR and Unbraked TWR

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●

A recommended tongue weight varies in accordance with the types of trailers
or towing as described below.

●

To ensure the recommended values shown below, the trailer must be loaded
by referring to the following instructions.

• Tongue Weight

The gross trailer weight should be distributed so that the tongue weight is
9% to 11%. 
(Tongue weight/Gross trailer weight x 100 = 9% to 11%)

Gross trailer weight
Tongue weight

The gross trailer weight, gross axle weight and tongue weight can be mea-
sured with platform scales found at a highway weighing station, building
supply company, trucking company, junk yard, etc.

Trailer hitch assemblies have different weight capacities. Lexus recommends the
use of Lexus hitch/bracket for your vehicle. For details, contact your Lexus
dealer.

●

If you wish to install a trailer hitch, contact your Lexus dealer.

●

Use only a hitch that conforms to the gross trailer weight requirement of your
vehicle.

●

Follow the directions supplied by the hitch manufacturer.

●

Lubricate the hitch ball with a light coating 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
substances into the vehicle.

Trailer Tongue Weight

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Hitch

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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 coupler.

Most couplers are stamped with the

required trailer ball size.

Shank length

Protrudes beyond the bottom of the lock washer and nut by at least 2 threads.

Shank diameter

Matches the ball mount hole diameter size.

Weight carrying ball position: 
44.96 in. (1142 mm)
Hitch receiver pin hole position:
35.94 in. (913 mm)

Selecting trailer ball

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Trailer class

Typical trailer ball size

IV

2 5/16 in.

II and III

2 in.

I

1 7/8 in.

Positions for towing hitch receiver and hitch ball

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Use the wire harness stored in the rear
end under body.

■

Auto current cut-off function
In case of over current, the auto cut-off function stops the power flowing to the trailer

lights to prevent damage to the vehicle’s electrical system.
This function is activated when the rated current of any of the following trailer light circuit

components is exceeded:

●

Tail lights: maximum 7.8 A 

●

Stop/turn signal light (right): maximum 4.5 A

●

Stop/turn signal light (left): maximum 4.5 A

■

When the auto current cut function is activated
If a trailer light does not come on due to the activation of the auto current cut function,

the light system will need to be reset.
Follow the reset procedure shown below.

●

If a tail light does not come on, turn off the headlight switch.

●

If the right-side stop/turn signal light does not come on, put the turn signal in the off

position or remove foot from the brake pedal.

●

If the left-side stop/turn signal light does not come on, put the turn signal in the off posi-

tion or remove foot from the brake pedal.

If the emergency flashers do not operate, press the emergency flasher switch to turn

them off.
After the light system is reset, operate the light switches again to see if the lights operate

normally.
If the lights do not operate normally, have the vehicle inspected by your Lexus dealer.

Connecting trailer lights

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Your vehicle will handle differently when towing a trailer. Help to avoid an acci-
dent, death or serious injury, keep the following in mind when towing:

●

Speed limits for towing a trailer vary by state or province. Do not exceed the
posted towing speed limit.

●

Lexus recommends that the vehicle-trailer speed limit is 65 mph (104 km/h)
on a flat, straight, dry road. Do not exceed this limit, the posted towing speed
limit or the speed limit for your trailer as set forth in your trailer owner’s man-
ual, whichever is lowest. Instability of the towing vehicle-trailer combination
(trailer sway) increases as speed increases. Exceeding speed limits may cause
loss of control.

●

Before starting out, check the trailer lights, tires and the vehicle-trailer con-
nections. Recheck after driving a short distance.

●

Practice turning, stopping and reversing with the trailer attached in an area
away from traffic until you become accustomed to the feel of the vehicle-
trailer combination.

●

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
prolonged 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 dis-
tance 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 the trailer jackknifing and a
loss of vehicle 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 a turn.

●

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 wider than normal
turning radius.

●

Slow down before making a turn, in cross winds, on wet or slippery surfaces,
etc.
Increasing vehicle speed can destabilize the trailer.

●

Take care when passing other vehicles. Passing requires considerable dis-
tance. After passing a vehicle, do not forget the length of your trailer, and be
sure you have plenty of room before changing lanes.

Trailer towing tips

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To maintain engine braking efficiency and charging system performance
when using engine braking, do not put the transmission in D. (

P. 246)

●

Instability happens more frequently when descending steep or long downhill
grades. Before descending, slow down and downshift. Do not make sudden
downshifts while descending steep or long downhill grades.

●

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.

●

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, imme-
diately turn off the air conditioning (if in use), pull your vehicle off the road and
stop in a safe spot. (

P. 702)

●

Always place wheel blocks under both the vehicle’s and the trailer’s wheels
when parking. Put the transmission in P and apply the parking brake. Avoid
parking on a slope, but if unavoidable, do so only after performing the follow-
ing:

Apply the brakes and keep them applied.
Have someone place wheel blocks under both the vehicle’s and trailer’s
wheels.
When the wheel blocks are in place, release the brakes slowly until the
blocks absorb the load.
Shift into P and apply the parking brake.
Turn off the hybrid system.

●

When restarting after parking on a slope:

With the transmission in P, start the hybrid system. Be sure to keep the
brake pedal depressed.
Shift into a forward gear. If reversing, shift into R.
If the parking brake is in manual mode, release the parking brake.
(

P. 254)

Release the brake pedal, and slowly pull or back away from the wheel
blocks. Stop and apply the brakes.
Have someone retrieve the blocks.

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Matching trailer ball height to trailer coupler height

■

Before towing
Check that the following conditions are met:

●

Ensure that your vehicle’s tires are properly inflated. (

P. 717)

●

Trailer tires are inflated according to the trailer manufacturer’s recommendation.

●

All trailer lights work as required by law.

●

All lights work each time you connect them.

●

The trailer ball is set at the proper height for the coupler on the trailer.

●

The trailer is level when it is hitched.

Do not drive if the trailer is not level, and check for improper tongue weight, overload-

ing, 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 regula-

tions. If they do not, install rear view mirrors appropriate for towing purposes.

■

AVS (adaptive variable suspension system) (if equipped) 
The suspension can be switched for improvement in driveability. (

P. 383)

No matter which class of tow hitch

applies, for a more safe trailer hookup,

the trailer ball setup must be the proper

height for the coupler on the trailer.

Coupler
Trailer ball

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Break-in schedule
If your vehicle is new or equipped with any new power train components (such as an

engine, hybrid transmission, rear differential or wheel bearing), Lexus recommends that

you do not tow a trailer until the vehicle has been driven for over 500 miles (800 km).
After the vehicle has been driven for over 500 miles (800 km), you can start towing.

However, for the next 500 miles (800 km), drive the vehicle at a speed of less than

50 mph (80 km/h) when towing a trailer, and avoid full throttle acceleration.

■

Maintenance

●

If you tow a trailer, your vehicle will require more frequent maintenance due to the addi-

tional load. (See “Warranty and Services Guide”, “Owner’s Manual Supplement” or

“Scheduled Maintenance”.)

●

Retighten the fixing bolts of the towing ball and bracket after approximately 600 miles

(1000 km) of trailer towing.

■

If trailer sway occurs
One or more factors (crosswinds, passing vehicles, rough roads, etc.) can adversely

affect handling of your vehicle and trailer, causing instability.

●

If trailer swaying occurs:
• Firmly grip the steering wheel. Steer straight ahead.

Do not try to control trailer swaying by turning the steering wheel.

• Begin releasing the accelerator pedal immediately but very gradually to reduce

speed.

Do not increase speed. Do not apply vehicle brakes.

If you make no extreme correction with the steering or brakes, your vehicle and trailer

should stabilize. (if enabled, Trailer Sway Control can also help to stabilize the vehicle and

trailer.)

●

After the trailer swaying has stopped:
• Stop in a safe place. Get all occupants out of the vehicle.

• Check the tires of the vehicle and the trailer.

• Check the load in the trailer.

Make sure the load has not shifted.

Make sure the tongue weight is appropriate, if possible.

• Check the load in the vehicle.

Make sure the vehicle is not overloaded after occupants get in.

If you cannot find any problems, the speed at which trailer swaying occurred is beyond

the limit of your particular vehicle-trailer combination.

Drive at a lower speed to prevent instability. Remember that swaying of the towing vehi-

cle-trailer increases as speed increases.

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WARNING

■

Trailer towing precautions
To tow a trailer safely, use extreme care and drive the vehicle in accordance with the

trailer’s characteristics and operating conditions. Failure to do so could cause an acci-

dent resulting in death or serious injury. Vehicle stability and braking performance are

affected by trailer stability, brake setting and performance, and the hitch. Your vehicle

will handle differently when towing a trailer.

■

To avoid accident or injury

●

Do not exceed the TWR, unbraked TWR, GCWR, GVWR or GAWR.

●

If the gross trailer weight is over 2000 lb. (907 kg), a sway control device with suffi-

cient capacity is required.

●

Adjust the tongue weight within the appropriate range. Place heavier loads as close

to the trailer axle as possible.

●

Do not exceed 65 mph (104 km/h), the posted towing speed limit or the speed limit

for your trailer as set forth in your trailer owner’s manual, whichever is lowest. Slow

down sufficiently before making a turn, in cross winds, on wet or slippery surface, etc.

to help avoid an accident. If you experience a vehicle-trailer instability from reducing

a certain speed, slow down and make sure you keep your vehicle speed under the

speed of which you experience the instability.

●

Do not make jerky, abrupt or sharp turns.

●

Do not apply the brakes suddenly as you may skid, resulting in jackknifing and loss of

vehicle control. This is especially true on wet or slippery surfaces.

●

Do not exceed the trailer hitch assembly weight, gross vehicle weight, gross axle

weight and trailer tongue weight capacities.

●

Do not use the following systems when trailer towing.
• Dynamic radar cruise control with full-speed range

• LKA (Lane-Keeping Assist)

• PCS (Pre-Collision system)

• BSM (Blind Spot Monitor)

*

*

: If equipped

●

Slow down and downshift before descending steep or long downhill grades. Do not

make sudden downshifts while descending steep or long downhill grades.

●

Vehicle-trailer instability is more likely on steep long downhills. Before descending

steep or long downhill grades, slow down and downshift. Do not make sudden down-

shifts when descending steep or long downhill grades. Avoid holding the brake pedal

down too long or applying the brakes too frequently. This could cause the brakes to

overheat and result in reduced braking efficiency.

●

Do not tow a trailer when the compact spare tire is installed on your vehicle.

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WARNING

■

Hitch
Trailer hitch assemblies have different weight capacities established by the hitch manu-

facturer. 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 assem-

bly 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 death or serious personal injuries.

■

When towing a trailer
Lexus recommends trailers with brakes that conform to any applicable federal and

state/provincial regulations.

●

If the gross trailer weight exceeds unbraked TWR, trailer brakes are required. Lexus

recommends trailers with brakes that conform to all applicable federal and state/pro-

vincial regulations.

●

Never tap into your vehicle’s hydraulic system, as this will lower the vehicle’s 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 danger of

the trailer wandering into another lane.

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 directly splice trailer lights
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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Trailer towing (vehicles without towing package)

Lexus does not recommend towing a trailer with your vehicle. Lexus also does
not recommend the installation of a tow hitch or the use of a tow hitch carrier
for a wheelchair, scooter, bicycle, etc. Your vehicle is not designed for trailer
towing or for the use of tow hitch mounted carriers.

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Dinghy towing

Your vehicle is not designed to be dinghy towed (with 4 wheels on the ground)
behind a motor home. 

NOTICE

■

To avoid serious damage to your vehicle
Do not tow your vehicle with the four wheels on the ground.

■

To prevent causing serious damage to the hybrid transmission and Hybrid AWD sys-

tem
Never tow this vehicle with any of the wheels

on the ground. This may cause serious damage

to the hybrid transmission and AWD system.

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4-2. Driving procedures

Check that the parking brake is set.
Check that the shift lever is in P.
Firmly depress the brake pedal.

 and a message will be displayed on the multi-information display. 

If it is not displayed, the hybrid system cannot be started.

Press the power switch shortly and
firmly.

When operating the power switch, one

short, firm press is enough.

It is not necessary to press and hold the

switch.
If the “READY” indicator turns on, the

hybrid system will operate normally.
Continue depressing the brake pedal

until the “READY” indicator is illumi-

nated.
The hybrid system can be started from

any power switch mode.

Check that the “READY” indicator is illuminated.

The vehicle will not move when the “READY” indicator is off.

Power (ignition) switch

Performing the following operations when carrying the electronic key on your
person starts the hybrid system or changes power switch modes.

Starting the hybrid system

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