LEXUS RX350 2019 Owners Manual

220 4-1. Before driving
RX350/RX350L_U ●
A recommended tongue weight varies in accordance with the types of trailers
or towing as described below. ●
To ensure the recommended values show n below, the trailer must be loaded
by referring to the following instructions.
• Tongue Weight
The gross trailer weight should be dist ributed 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 ve hicle. 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 ar e not towing a trailer. After removing
the hitch, seal any mounting hole in th e vehicle body to prevent entry of any
substances into the vehicle.Trailer Tongue Weight 1
2
Hitch

2214-1. Before driving
4
Driving
RX350/RX350L_U 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. 
RX350
Weight carrying ball position:
44.96 in. (1142 mm)
Hitch receiver pin hole position:
35.94 in. (913 mm) 
RX350L
Weight carrying ball position:
49.72 in. (1263 mm)
Hitch receiver pin hole position:
45.08 in. (1145 mm)Selecting trailer ball 1
2
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 3
4
1
2
1
2

222 4-1. Before driving
RX350/RX350L_U 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 cu t function is activated
If a trailer light does not come on due to th e 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 lig ht 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

2234-1. Before driving
4
Driving
RX350/RX350L_U 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 tr ailer vary by state or province. Do not exceed the
posted towing speed limit. ●
Lexus recommends that the vehicle-traile r speed limit is 65 mph (104 km/h)
on a flat, straight, dry road. Do not exce ed 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 incr eases. 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 acc ustomed to the feel of the vehicle-
trailer combination. ●
Reversing with a trailer attached is di fficult 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 with out a trailer attached.) Avoid sharp or
prolonged turning. Have someone guid e 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, re sulting in the trailer jackknifing and a
loss of vehicle control. This is especi ally true on wet or slippery surfaces.●
Avoid jerky starts or sudden acceleration. ●
Avoid jerky steering and sharp turns, an d 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 fo rget the length of your trailer, and be
sure you have plenty of room before changing lanes.Trailer towing tips

224 4-1. Before driving
RX350/RX350L_U ●
To maintain engine braking efficien cy and charging system performance
when using engine braking, do not put th e transmission in D. If in the M or S
mode, the transmission shift range po sition must be in 6 or lower. (  P. 240)●
Instability happens more fr equently when descending steep or long downhill
grades. Before descending, slow down and downshift. Do not make sudden
downshifts while descending st eep 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, yo ur 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 temperat ure 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. 692)●
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 engine.●
When restarting afte r parking on a slope:
With the transmission in P, start the en gine. 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. 248)
Release the brake pedal, and slowly pull or back away from the wheel
blocks. Stop and apply the brakes.
Have someone retrieve the blocks. 1
2
3
4
5
1
2
3
4
5

2254-1. Before driving
4
Driving
RX350/RX350L_U ■
Matching trailer ball height to trailer coupler height
■
Before towing
Check that the followin g conditions are met:●
Ensure that your vehicle’s tires are properly inflated. (  P. 704)●
Trailer tires are inflated a ccording 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 to ngue 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 fo r improvement in driveability. (  P. 379)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 1
2

226 4-1. Before driving
RX350/RX350L_U ■
Break-in schedule
If your vehicle is new or equipped with any new power train components (such as an
engine, transaxle, transfer (AWD models), rear differential (AWD models) 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 requir e 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 ba ll and bracket after approximately 600 miles
(1000 km) of trailer towing. ■
If trailer sway occurs
One or more factors (crosswinds, passing ve hicles, rough roads, etc.) can adversely
affect handling of your vehicle and trailer, causing instability. ●
If trailer swaying occurs:
• Firmly grip the steering wh eel. Steer straight ahead.
Do not try to control trailer sway ing by turning the steering wheel.
• Begin releasing the accelerator pedal im mediately but very gradually to reduce
speed.
Do not increase speed. Do not apply vehicle brakes.
If you make no extreme correction with the st eering or brakes, your vehicle and trailer
should stabilize. (if enabled, Trailer Sway Control can also he lp to stabilize the vehicle and
trailer.) ●
After the trailer sw aying 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 ov erloaded 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.

2274-1. Before driving
4
Driving
RX350/RX350L_U 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 conditio ns. Failure to do so could cause an acci-
dent resulting in deat h or serious injury. Vehicle stab ility and braking performance are
affected by trailer stability, brake setting an d 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 approp riate 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 trai ler owner’s manual, whichever is lowest. Slow
down sufficiently before making a turn, in cr oss winds, on wet or slippery surface, etc.
to help avoid an accident. If you experien ce a vehicle-trailer in stability from reducing
a certain speed, slow down and make sure you keep your vehicle speed under the
speed of which you expe rience the instability.●
Do not make jerky, abrupt or sharp turns. ●
Do not apply the brakes suddenly as you ma y 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 cont rol 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 do wnhill grades. Avoid ho lding 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 sp are tire is installed on your vehicle.

228 4-1. Before driving
RX350/RX350L_U WARNING ■
Hitch
Trailer hitch assemblies have different weight capacities established by the hitch manu-
facturer. Even though the vehicle may be phys ically 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 co upling 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 splic e trailer lights. Directly splicin g trailer lights may damage your
vehicle’s electrical system and cause a malfunction.

2294-1. Before driving
4
Driving
RX350/RX350L_UTrailer 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.