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4-1. Before driving
■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. 606)
● Trailer tires are inflated according to the trailer manufacturer’s recommen-
dation.
● 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,
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 tow-
ing purposes.
■ Break-in schedule
If your vehicle is new or equipped with any new power train components
(such as an engine, transmission, differ ential or wheel bearing), Toyota rec-
ommends 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. No matter which class of tow hitch
applies, for a safe trailer hookup, the
trailer ball setup on must be proper height
for the coupler on the trailer.
Coupler
Trailer ball
1
2

SIENNA_OM_OM08007U_(U)
2214-1. Before driving
4
Driving
■Maintenance
●If you tow a trailer, your vehicle will require more frequent maintenance due
to the additional load. (See “Scheduled Maintenance Guide” or “Owner’s
Manual Supplement”.)
● 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.
● 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 vehicle-trailer increases as speed increases.

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4-1. Before driving
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 accident resulting in death or serious injury. Vehicle stability
and braking performance are affected by trailer stability, brake setting and
performance, and the hitch. Your vehi cle 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 sufficient 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 sur-
faces.
● Do not exceed the trailer hitch assembly weight, gross vehicle weight,
gross axle weight and trailer tongue weight capacities.

SIENNA_OM_OM08007U_(U)
2234-1. Before driving
4
Driving
WARNING
■To avoid accident or injury
●Do not use cruise control when towing.
● 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 downshifts 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.
● Vehicles with compact spare tire: Do not tow a trailer when the compact
spare tire is installed on your vehicle.
■ Hitch
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 death or serious personal injuries.
■ When towing a trailer
Toyota recommends trailers with brakes that conform to any applicable fed-
eral and state/provincial regulations.
●If the gross trailer weight exceeds unbraked TWR, trailer brakes are
required. Toyota recommends trailers with brakes that conform to all appli-
cable federal and state/provincial regulations.
● Never tap into your vehicle’s hydraulic system, as this will lower the vehi-
cle’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 Toyota 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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6-3. Using the storage features
■Coin holder (type B)
Nickels, quarters and dimes can be stored
separately.
WARNING
■Maximum storage weight (type A)
Do not store items heavier than 0.4 lb. (200 g).
Doing so may cause the auxiliary box to open and the items inside may fall
out, resulting in an accident.

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4997-3. Do-it-yourself maintenance
7
Maintenance and care
■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on a tire.
●You have tire damage such as cuts, splits, cracks deep enough to
expose the fabric, and bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size
or location of a cut or other damage
If you are not sure, consult with your Toyota dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not reg-
istered, the tire pressure warning system will not work properly. After driv-
ing for about 20 minutes, the tire pressure warning light blinks for
1 minute and stays on to indicate a system malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even
if it has seldom or never been used or damage is not obvious.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation
pressure checks. Make sure to check tire inflation pressure as part of
your routine of daily vehicle checks.
■Maximum load of tire
Check that the number given by dividing the maximum load by 1.10 of the
replacement tire is greater than 1/ 2 of the Gross Axle Weight Ratings
(GAWR) of either the front axle or the rear axle, whichever is greater.
For the GAWR, see the Certification
Label. For the maximum load of the tire,
see the load limit at maximum cold tire
inflation pressure mentioned on the
sidewall of the tire. ( P. 612)

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SIENNA_OM_OM08007U_(U)
7-3. Do-it-yourself maintenance
■Instructions for checking tire inflation pressure
When checking tire inflation pressure, observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at least 3 hours or has not been
driven for more than 1 mile or 1.5 km, you will get an accurate cold tire
inflation pressure reading.
●Always use a tire pressure gauge.
It is difficult to judge if a tire is properly inflated based only on its appear-
ance.
●It is normal for the tire inflation pressure to be higher after driving as
heat is generated in the tire. Do not reduce tire inflation pressure after
driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle is
balanced.
WARNING
■Proper inflation is critical to save tire performance
Keep your tires properly inflated.
If the tires are not properly inflated, the following conditions may occur
which could lead to an accident resulting in death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts result ing from overheated tires
●Air leaking from between tire and wheel
●Wheel deformation and/or tire damage
●Greater possibility of tire damage while driving (due to road hazards,
expansion joints, sharp edges in the road, etc.)
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to put the tire valve caps back on.
If a valve cap is not installed, dirt or moisture may get into the valve and
cause an air leak, resulting in decreased tire inflation pressure.

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7-3. Do-it-yourself maintenance
7
Maintenance and care
Wheels
When replacing wheels, care should be taken to ensure that they are
equivalent to those removed in load capacity, diameter, rim width and
inset
*.
Replacement wheels are available at your Toyota dealer.
*: Conventionally referred to as “offset”.
Toyota does not recommend using the following:
● Wheels of different sizes or types
● Used wheels
● Bent wheels that have been straightened
● Use only Toyota wheel nuts and wrenches designed for use with
your aluminum wheels.
● When rotating, repairing or changi ng your tires, check that the
wheel nuts are still tight after driving 1000 miles (1600 km).
● Be careful not to damage the aluminum wheels when using tire
chains.
● Use only Toyota genuine balance weights or equivalent and a plas-
tic or rubber hammer when balancing your wheels.
■When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning
valves and transmitters that allow the tire pressure warning system to
provide advanced warning in the event of a loss in tire inflation pressure.
Whenever wheels are replaced, tire pressure warning valves and trans-
mitters must be installed. ( P. 497)
If a wheel is bent, cracked or heavily corroded, it should be
replaced.
Otherwise, the tire may separate from the wheel or cause a loss
of handling control.
Wheel selection
Aluminum wheel precautions