2003 TOYOTA SIENNA Owners Manual

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2452003 MY SIENNA (OM45410U)
Do not use your parking brake when
there is a possibility it could freeze.
When parking, put the transmission into
“P” and block the rear wheels. Do not use
the parking brake, or snow or water accu-
mulated in and around the parking brake
mechanism may freeze, making it hard to
release.
Keep ice and snow from accumulating
under the fenders.
Ice and snow built up under your fenders
can make steering difficult. During bad
winter driving, stop and check under the
fenders occasionally.
Depending on where you are driving,
we recommend you carry some emer-
gency equipment.
Some of the things you might put in the
vehicle are tire chains, window scraper,
bag of sand or salt, flares, small shovel,
jumper cables, etc.
Your vehicle is not designed to be
dinghy towed (with four wheels on the
ground) behind a motorhome.
NOTICE
Do not tow your vehicle with four
wheels on the ground. This may
cause serious damage to your vehicle.
Your vehicle is designed primarily as a
passengerandloadcarrying vehicle. Tow-
ing a trailer will have an adverse effect 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 safe-
ty and the safety of others, you must not
overload your vehicle or trailer. Ask your
local Toyota dealer for further details be-
fore towing.
WEIGHT LIMITS
Before towing, make sure the total trail-
er weight, gross combination 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, build-
ing supply company, trucking company,
junk yard, etc.
Dinghy towing Trailer towing

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CAUTION
The maximum gross trailer weight
(trailer weight plus cargo weight)
must never exceed the following. Without towing package
907 kg (2000 lb.)
With towing package 1587 kg (3500 lb.)
If towing a trailer and cargo weigh-
ing over 907 kg (2000 lb.), it is
necessary to use a sway control de-
vice 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
the following. Without towing package 3129 kg (6900 lb.)
With towing package 3537 kg (7800 lb.)
Exceeding the maximum weight of
the trailer, the vehicle, or the ve-
hicle and trailer combination, can
cause an accident resulting in seri-
ous personal injuries.
Trailer hitch assemblies have differ-
ent weight capacities established by
the hitch manufacturer. Even though
the vehicle may be physically capa-
ble of towing a higher weight, the
operator must determine the maxi-
mum weight rating of the particular
hitch assembly and never exceed
the maximum weight rating speci-
fied for the trailerhitch. Exceeding
the maximum weight rating set by
the trailer hitch manufacturer can
cause an accident resulting in seri-
ous personal injuries.
The gross vehicle weight must not
exceed the Gross Vehicle Weight
Rating (GVWR) indicated on the
Certification Label. The gross ve-
hicle weight is the sum of weights
of the unloaded vehicle, driver, pas-
sengers, 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 Gross
Axle Weight Rating (GAWR) listed
on the Certification Label.

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Total trailer weight Tongue loadTongue load
Total trailer weight 
100 = 9 to 11%
(∗
1)
or 15% (∗
2)
The trailer cargo load should be
distributed so that the tongue load
is 9 to 11% for weight carrying
hitch
(∗
1) or 15% for weight distrib-
ut i ng hi t ch ( ∗
2) of the total trailer
weight, not exceeding the maximum
load of the following.
Weight carrying hitch
Without towing package 90 kg (200 lb.)
With towing package
158 kg (350 lb.)
Weight distributing hitch With towing package
238 kg (525 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.
HITCHES
If you wish to install a trailer hitch, you
should consult with your Toyota dealer.
Use only a hitch recommended by the
hitch manufacturer and the one which
conforms to the total trailer weight
requirement.
The hitch must be bolted securely to
the vehicle frame and installed accord-
ing to the hitch manufacturer ’s instruc-
tions.
The hitch ball and king pin should have
a light coat of grease.
Toyota recommends removing the trail-
er hitch whenever you are not towing
a trailer to reduce the possib ility of
additional damage caused by the hitch
if your vehicle is struck from behind.
After removing the hitch, seal any
mounting holes in the vehicle body to
prevent entry of pollutants such as ex-
haust fumes, dirt, water, etc.
NOTICE
Do not use axlemounted hitches as
they can cause damage to the axle
housing, wheel bearings, wheels or
tires. Also, never install a hitch which
may interfere with the normal function
of an Energy Absorbing Bumper, if so
equipped.
BRAKES AND SAFETY CHAINS
Toyota recommends trailers with
brakes that conform to any applica-
ble federal and state/provincial regu-
lations.

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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 dam-
aged or separated. For correct safety
chain procedures, follow the hitch or
trailer manufacturer ’s recommenda-
tions.
CAUTION
If the total trailer weight exceeds
453 kg (1000 lb.), trailer brakes are
required.
Never tap into your vehicle’s hy-
draulic system as it would 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 danger of the
trailer wandering over into another
lane.
TIRES
Ensure that your vehicle’s tires are
properly inflated. Adjust the tire pres-
sure to the recommended cold tire
pressure indicated below. (See Section
72 and Section 8 for instructions.):
Tire pressure, kPa (kgf/cm
2 or bar, psi)
240 (2.4, 35)
The trailer tires should be inflated to
the pressure recommended by the trail-
er manufacturer in respect to the total
trailer weight.
TRAILER LIGHTS
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 trail-
er. Check for correct operation of the
turn signals and stop lights each time
you hitch up. Direct splicing may dam-
age your vehicle’s electrical system
and cause a malfunction of your lights. BREAKIN SCHEDULE
Toyota recommends that you do not
tow a trailer with a new vehicle or a
vehicle with any new power train com-
ponent (engine, transmission, differen-
tial, 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 “Scheduled Maintenance Guide” or
“Owner ’s Manual Supplement”.
Retighten all fixing bolts of the towing
ball and bracket after approximately
1000 km (600 miles) of trailer driving.
PRETOWING SAFETY CHECK
Check that your vehicle remains level
when a loaded or unloaded trailer is
hitched. Do not drive if the vehicle has
an abnormal noseup or nosedown
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.

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Check that your rear view mirrors con-
form to any applicable federal, state/
provincial or local regulations. If not,
install the rear view mirrors required
for towing purpose.
TRAILER TOWING TIPS
When towing a trailer, your vehicle will
handle differently than when not tow-
ing. The three main causes of vehicle
trailer accidents are driver error, exces-
sive speed and improper trailer loading.
Keep these in mind when towing:
Before starting out, check operation of
the lights and all vehicletrailer connec-
tions. After driving a short distance,
stop and recheck the lights and con-
nections. Before actually towing a trail-
er, practice turning, stopping and back-
ing with a trailer in an area away from
traffic until you learn the feel.
Backing with a trailer 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 the right. (This pro-
cedure is generally opposite to that
when backing without a trailer.) Also,
just turn the steering wheel a little at
a time, avoiding sharp or prolonged
turning. Have someone guide you when
backing to reduce the risk of an acci-
dent.
Because stopping distance may be in-
creased, vehicletovehicle distance
should be increased when towing a
trailer. For each 16 km/h (10 mph) of
speed, allow at least one vehicle and
trailer length between you and the ve-
hicle ahead. 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 accelera-
tion.
Avoid jerky steering and sharp turns.
The trailer could hit your vehicle in a
tight turn. Slow down before making a
turn to avoid the necessity of sudden
braking.
Remember that when making a turn,
the trailer wheels will be closer than
the vehicle wheels to the inside of the
turn. Therefore, compensate for this by
making a larger than normal turning
radius with your vehicle.
Crosswinds and rough roads will ad-
versely affect handling of your vehicle
and trailer, causing sway. Pay attention
to the rear from time to time to pre-
pare yourself for being passed by large
trucks or buses, which may cause your
vehicle and trailer to sway. If swaying
happens, firmly grip the steering wheel
and reduce speed immediately but
gradually. Never increase speed. Steer
straight ahead. If you make no extreme
correction with the steering or brakes,
the vehicle and trailer will stabilize.
Be careful when passing other ve-
hicles. Passing requires considerable
distance. After passing a vehicle, do
not forget the length of your trailer and
be sure you have plenty of room be-
fore changing lanes.
In order to maintain engine braking effi-
ciency, do not use overdrive.

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Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30C [85 F]) when going up a long or
steep grade with a trailer. If the engine
coolant temperature gauge indicates
overheating, immediately turn off the air
conditioning (if in use), pull off the road
and stop in a safe spot. Refer to “If
your vehicle overheats” in Section 4.
Always place wheel blocks under both
the vehicle and trailer wheels when
parking. Apply the parking brake firmly.
Put the transmission in “P”. Avoid park-
ing on a slope with a trailer, but if it
cannot be avoided, do so only after
performing the following:
1. Apply the brakes and hold.
2. Have someone place wheel blocks un- der both the vehicle and trailer wheels.
3. When the wheel blocks are in place, release your brakes slowly until the
blocks absorb the load.
4. Apply the parking brake firmly.
5. Shift into “P” and turn off the engine. When restarting out after parking on a
slope:
1. With the transmission in “P” position, start the engine. Be sure to keep the
brake pedal depressed.
2. Shift into gear.
3. Release the parking brake and brake pedal and slowly pull or back away
from the wheel blocks. Stop and apply
your brakes.
4. Have someone retrieve the blo cks.
CAUTION
Do not exceed 72 km/h (45 mph) or
the posted towing speed limit,
whichever is lower. Because insta-
bility (swaying) of a towing vehicle
trailer combination usually in-
creases as the speed increases, ex-
ceeding 72 km/h (45 mph) may
cause loss of control.
Slow down and downshift before
descending steep or long downhill
grades. Do not make sudden down-
shifts.
Avoid holding the brake pedal down
too long or too frequently. This
could cause the brakes to overheat
and result in reduced braking effi-
ciency.

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Improving fuel economy is easy—just take
it easy. It will help make your vehicle last
longer, too. Here are some specific tips
on how to save money on both fuel and
repairs:
Keep your tires inflated at the cor-
rect pressure. Underinflation causes
tire wear and wastes fuel. See Section
72 for instructions.
Do not carry unneeded weight in
your vehicle. Excess weight puts a
heavier load on the engine, causing
greater fuel consumption.
Avoid lengthy warmup idling. Once
the engine is running smoothly, begin
driving—but gently. Remember, howev-
er, that on cold winter days this may
take a little longer.
Keep the automatic transmission
overdrive turned on when engine
braking is not required. Driving with
the overdrive off will reduce the fuel
economy. (For details, see “Automatic
transmission” in Section 16.)
Accelerate slowly and smoothly.
Avoid jackrabbit starts. Get into high
gear as quickly as possible.
Avoid long engine idling. If you have
a long wait and you are not in traffic,
it is better to turn off the engine and
start again later.
Avoid engine lugging or overrev-
ving. Use a gear position suitable for
the road on which you are travelling.
Avoid continuous speeding up and
slowing down. Stopandgo driving
wastes fuel.
Avoid unnecessary stopping and
braking. Maintain a steady pace. Try
to time the traffic signals so you only
need to stop as little as possible or
take advantage of through streets to
avoid traffic lights. Keep a proper dis-
tance from other vehicles to avoid sud-
den braking. This will also reduce wear
on your brakes.
Avoid heavy traffic or traffic jams
whenever possible.
Do not rest your foot on the brake
pedal. This causes premature wear,
overheating and poor fuel economy.
Maintain a moderate speed on high-
ways. The faster you drive, the greater
the fuel consumption. By reducing your
speed, you will cut down on fuel con-
sumption.
Keep the front wheels in proper
alignment. Avoid hitting the curb and
slow down on rough roads. Improper
alignment not only causes faster tire
wear but also puts an extra load on
the engine, which, in turn, wastes fuel.
Keep the bottom of your vehicle free
from mud, etc. This not only lessens
weight but also helps prevent corro-
sion.
Keep your vehicle tunedup and in
top shape. A dirty air cleaner, improp-
er valve clearance, dirty plugs, dirty oil
and grease, brakes not adjusted, etc.
all lower engine performance and con-
tribute to poor fuel economy. For longer
life of all parts and lower operating
costs, keep all maintenance work on
schedule, and if you often drive under
severe conditions, see that your vehicle
receives more frequent maintenance.
(For scheduled maintenance informa-
tion, please refer to the “Scheduled
Maintenance Guide” or “Owner ’s Manu-
al Supplement”.)
How to save fuel and make
your vehicle last longer

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CAUTION
Never turn off the engine to coast
down hills. Your power steering and
brake booster will not function with-
out the engine running. Also, the
emission control system operates
properly only when the engine is run-
ning.