2014 TOYOTA SIENNA traction

SIENNA_OM_OM45483U_(U)
29
CAUTION
■General precautions while driving
Driving under the influence: Never drive your vehicle when under the influ-
ence of alcohol or drugs that have impaired your ability to operate your vehi-
cle. Alcohol and certain drugs delay reaction time, impair judgment and
reduce coordination, which could lead to an accident that could result in
death or serious injury.
Defensive driving: Always drive defensively. Anticipate mistakes that other
drivers or pedestrians might make and be ready to avoid accidents.
Driver distraction: Always give your full attention to driving. Anything that dis-
tracts the driver, such as adjusting controls, talking on a cellular phone or
reading can result in a collision with resulting death or serious injury to you,
your occupants or others.
■ General precaution regarding children’s safety
Never leave children unattended in the vehicle, and never allow children to
have or use the key.
Children may be able to start the vehicle or shift the vehicle into neutral.
There is also a danger that children may injure themselves by playing with
the cigarette lighter, the windows, the moon roof, or other features of the
vehicle. In addition, heat build-up or ex tremely cold temperatures inside the
vehicle can be fatal to children.

331
2-4. Using other driving systems
2
When driving
SIENNA_OM_OM45483U_(U)
Driving assist systems
To help enhance driving safety and performance, the following sys-
tems operate automatically in res ponse to various driving situations.
Be aware, however, that these systems are supplementary and
should not be relied upon too heavi ly when operating the vehicle.
■ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface
■Brake assist
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation
■VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning
on slippery road surfaces
■Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road
surfaces by controlling steering performance.
■TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spin-
ning when starting the vehicle or accelerating on slippery roads
■Hill-start assist control (if equipped)
P. 337
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel

694 4-3. Do-it-yourself maintenance
SIENNA_OM_OM45483U_(U)
■Tire types
1 Summer tiresSummer tires are high-speed performance tires best suited to highway
driving under dry conditions. Sinc e summer tires do not have the same
traction performance as snow tire s, summer tires are inadequate for
driving on snow-covered or icy roads. For driving on snow-covered
roads or icy roads, the use of snow tires is recommended. When
installing snow tires, be sure to replace all four tires.
2 All season tires All season tires are designed to provide better traction in snow and to
be adequate for driving in most winter conditions, as well as for use
year round. All season tires, however, do not have adequate traction
performance compared with snow tires in heavy or loose snow. Also,
all season tires fall short in acceleration and handling performance
compared with summer tires in highway driving.
3Snow tires
For driving on snow-covered roads or icy roads, we recommend using
snow tires. If you need snow tires, select tires of the same size, con-
struction and load capacity as the or iginally installed tires. Since your
vehicle has radial tires as original equipment, make sure your snow
tires also have radial construction. Do not install studded tires without
first checking local regulations for possible restriction. Snow tires
should be installed on all wheels. ( P. 369)

5
When trouble arises
793
5-2. Steps to take in an emergency
SIENNA_OM_OM45483U_(U)
If the vehicle becomes stuck
CAUTION
■When attempting to free a stuck vehicle
If you choose to push the vehicle back and forth to free it, make sure the sur-
rounding area is clear to avoid striki ng other vehicles, objects or people. The
vehicle may also lunge forward or lu nge back suddenly as it becomes free.
Use extreme caution.
■ When shifting the shift lever
Be careful not to shift the shift lever with the accelerator pedal depressed.
This may lead to unexpected rapid acceleration of the vehicle that may
cause an accident resulting in death or serious injury.
Carry out the following procedures if the tires spin or the vehicle
becomes stuck in mud, dirt, or snow.
Stop the engine. Set the parki ng brake and shift the shift
lever to P.
Remove the mud, snow, or sand from around the stuck tire.
Place wood, stones or some other material under the tires
to help provide traction.
Restart the engine.
Shift the shift lever to the D or R position and carefully apply
the accelerator to free the vehicle.
Turn off TRAC and Enhanced VSC if these functions are hamper-
ing your attempts to free the vehicle. (P. 333)
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818 6-1. Specifications
SIENNA_OM_OM45483U_(U)
Tire section namesBead
Sidewall
Shoulder
Tread
Belt
Inner liner
Reinforcing rubber
Carcass
Rim lines
Bead wires
Chafer
Uniform Tire Quality GradingThis information has been prepared in accordance with regulations
issued by the National Highway Tr affic Safety Administration of the
U.S. Department of Transportation.
It provides the purchasers and/or prospective purchasers of Toyota
vehicles with information on uniform tire quality grading.
Your Toyota dealer will help answ er any questions you may have as
you read this information.
■ DOT quality grades
All passenger vehicle tires mu st conform to Federal Safety
Requirements in addition to these grades. Quality grades can be
found where applicable on the tire sidewall between tread shoulder
and maximum section width.
For example: Treadwear 200 Traction AA Temperature A
ITY61C013

819
6-1. Specifications
6
Vehicle specifications
SIENNA_OM_OM45483U_(U)
■
Treadwear
The treadwear grade is a comparative rating based on the wear
rate of the tire when tested under controlled conditions on a speci-
fied government test course.
For example, a tire graded 150 would wear one and a half (1-1/2)
times as well on the government course as a tire graded 100.
The relative performance of tires depends upon the actual conditions
of their use, performance may differ significantly from the norm due
to variations in driving habits, service practices and differences in
road characteristics and climate.
■ Traction AA, A, B, C
The traction grades, from highest to lowest, are AA, A, B and C,
and they represent the tire’s ab ility to stop on wet pavement as
measured under controlled cond itions on specified government
test surfaces of asphalt and concrete.
A tire marked C may have poor traction performance.
Warning: The traction grade assigned to this tire is based on braking
(straight ahead) traction tests and does not include cornering (turn-
ing) traction.

825
6-1. Specifications
6
Vehicle specifications
SIENNA_OM_OM45483U_(U)
Tire related termMeaning
Maximum permissible
inflation pressure The maximum cold inflation pressure to which
a tire may be inflated
Measuring rim The rim on which a tire is fitted for physical
dimension requirements
Open splice Any parting at any junction of tread, sidewall, or
innerliner that extends to cord material
Outer diameter The overall diameter of an inflated new tire
Overall width The linear distance between the exteriors of
the sidewalls of an inflated tire, including eleva-
tions due to labeling, decorations, or protective
bands or ribs
Passenger car tire A tire intended for use on passenger cars, mul-
tipurpose passenger vehicles, and trucks, that
have a gross vehicle weight rating (GVWR) of
10,000 lb. or less
Ply A layer of rubber-coated parallel cords
Ply separation A parting of rubber compound between adja-
cent plies
Pneumatic tire A mechanical device made of rubber, chemi-
cals, fabric and steel or
other materials, that,
when mounted on an automotive wheel, pro-
vides the traction and contains the gas or fluid
that sustains the load
Radial ply tire A pneumatic tire in which the ply cords that
extend to the beads are laid at substantially 90
degrees to the centerline of the tread

826 6-1. Specifications
SIENNA_OM_OM45483U_(U)
Tire related termMeaning
Reinforced tire A tire designed to operate at higher loads and
at higher inflation pressures than the corre-
sponding standard tire
Section width The linear distance between the exteriors of
the sidewalls of an inflated tire, excluding ele-
vations due to labeling, decoration, or protec-
tive bands
Sidewall That portion of a tire between the tread and
bead
Sidewall separation The parting of the rubber compound from the
cord material in the sidewall
Snow tire A tire that attains a traction index equal to or
greater than 110, compared to the ASTM E-
1136 Standard Reference Test Tire, when
using the snow traction test as described in
ASTM F-1805-00, Standard Test Method for
Single Wheel Driving Traction in a Straight Line
on Snow-and Ice-Covered Surfaces, and which
is marked with an Alpine Symbol ( ) on at
least one sidewall
Te s t r i m The rim on which a tire is fitted for testing, and
may be any rim listed as appropriate for use
with that tire
Tread That portion of a tire that comes into contact
with the road
Tread rib A tread section running circumferentially
around a tire
Tread separation Pulling away of the tread from the tire carcass