2008 TOYOTA SIENNA wheel

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
CAUTION
Do not overestimate the antilock
brake system: Although the antilock
brake system assists in providing ve-
hicle control, it is still important to
drive with all due care and maintain
a moderate speed and safe distance
from the vehicle in front of you, be-
cause there are limits to the vehicle
stability and effectiveness of steering
wheel operation even with the anti
lock brake system on.
If tires grip performance exceeds its
capability, or if hydroplaning occurs
during high speed driving in the rain,
the antilock brake system does not
provide vehicle control.
Antilock brake system is not de-
signed to shorten the stopping dis-
tance: Always drive at the moderate
speed and maintain a safe distance
from the vehicle in front of you.
Compared with vehicles without an
antilock brake system, your vehicle
may require a longer stopping dis-
tance in the following cases:
Driving on rough, gravel or snow
covered roads.
Driving with tire chains installed.
Driving over the steps such as the
joints on the road.
Driving on roads where the road
surface is pitted or has other differ-
ences in surface height.
Install all 4 tires of specified size at
appropriate pressure: The antilock
brake system detects vehicle speeds
using the speed sensors for respec-
tive wheels’ turning speeds. The use
of tires other than specified may fail
to detect the accurate turning speed
resulting in a longer stopping dis-
tance.
Ty p e A
Ty p e B

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
“ABS” warning light
Vehicles without the vehicle stability
control system—
The light comes on when the engine
switch is turned to the “ON” position. If
the anti−lock brake system works properly,
the light turns off after a few seconds.
Thereafter, if either of the systems mal-
functions, the light comes on again.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate,
but the brake system still operates con-
ventionally.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate
but the brake assist system still operates.
In this case the wheels could lock up
during a sudden braking or braking on
slippery road surfaces. If either of the following conditions
occurs, this indicates a malfunction
somewhere in the components moni-
tored by the warning light system. Con-
tact your Toyota dealer as soon as
possible to service the vehicle.
The light does not come on when the
engine switch is turned to the “ON”
position, or remains on.
The light comes on while you are driv-
ing.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If the “ABS” warning light remains on
together with the brake system warn-
ing light, immediately stop your ve-
hicle at a safe place and contact your
Toyota dealer.
In this case, not only the antilock
brake system will fail but also the
vehicle will become extremely unsta-
ble during braking.
Vehicles with the vehicle stability con-
trol system—
The light comes on when the engine
switch is turned to the “ON” position. If
the anti −lock brake system and the brake
assist system work properly, the light
turns off after a few seconds. Thereafter,
if either of the systems malfunctions, the
light comes on again.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system, the brake assist
system, the traction control system and
the vehicle stability control system do not
operate, but the brake system still oper-
ates conventionally.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate
so that the wheels could lock up during
a sudden braking or braking on slippery
road surfaces.
If either of the following conditions
occurs, this indicates a malfunction
somewhere in the components moni-
tored by the warning light system. Con-
tact your Toyota dealer as soon as
possible to service the vehicle.

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
This illustration indicates typical tire
size.1. Tire use (P=Passenger car, T=Temporary use)
2. Section width (in millimeters)
3. Aspect ratio (tire height to section width)
4. Tire construction code (R=Radial, D=Diagonal)
5. Wheel diameter (in inches)
6. Load index (2 digits or 3 digits)
7. Speed symbol (alphabet with one letter)1. Section width
2. Tire height
3. Wheel diameter1. Bead
2. Sidewall
3. Shoulder
4. Tread
5. Belt
6. Inner liner
7. Reinforcing rubber
8. Carcass
9. Rim lines
10.Bead wires
11. Chafer
—Tire size —Name of each section of tire

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
Temperature A, B, C—T he tem per a-
ture grades are A (the highest), B,
and C, representing the tire’s resis-
tance to the generation of heat and
its ability to dissipate heat when
tested under controlled conditions on
a specified indoor laboratory test
wheel. Sustained high temperature
can cause the material of the tire to
degenerate and reduce tire life, and
excessive temperature can lead to
sudden tire failure. The grade C cor-
responds to a level of performance
which all passenger car tires must
meet under the Federal Motor Vehicle
Safety Standard No.109. Grades B
and A represent higher levels of per-
formance on the laboratory test wheel
than the minimum required by law.
Warning: The temperature grades for
this tire are established for a tire that
is properly inflated and not over-
loaded. Excessive speed, underinfla-
tion, or excessive loading, either sep-
arately or in combination, can cause
heat buildup and possible tire failure.

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
Ti r e relat ed ter mMeaning
Production options weight
the combined weight of those installed regular production options weighing
over 2.3 kg (5 lb.) in excess of those standard items which they replace,
not previously considered in curb weight or accessory weight, including
heavy duty brakes, ride levelers, roof rack, heavy duty battery, and special
trim
Rima metal support for a tire or a tire and tube assembly upon which the tire beads
are seated
Rim diameter (Wheel diameter)nominal diameter of the bead seat
Rim size designationrim diameter and width
Rim type designationthe industry of manufacturer ’s designation for a rim by style or code
Rim widt hnominal distance between rim flanges
Vehicle capacity weight
(Total load capacity)the rated cargo and luggage load plus 68 kg (150 lb.) times the vehicle’s desig-
nated seating capacity
Vehicle maximum load on the tirethe load on an individual tire that is determined by distributing to each axle
its share of the maximum loaded vehicle weight and dividing by two
Vehicle normal load on the tire
the load on an individual tire that is determined by distributing to each axle
its share of the curb weight, accessory weight, and normal occupant weight
(distributed in accordance with Table 1 that follows) and dividing by two
Weather sidethe surface area of the rim no t covered by the inflated tire
Beadthe part of the tire that is made of steel wires, wrapped or reinforced by ply
cords and that is shaped to fit the rim

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
Ti r e relat ed ter mMeaning
Passenger car tire
a tire intended for use on passenger cars, multipurpose passenger vehicles,
and trucks, that have a gross vehicle weight rating (GVWR) of 10,000 lb. or
less.
Plya layer of rubber−coated parallel cords
Ply separationa parting of rubber compound between adjacent plies
Pneumatic tire
a mechanical device made of rubber, chemicals, fabric and steel or other mate-
rials, that, when mounted on an automotive wheel, provides the traction and
contains the gas or fluid that sustains the load
Radial ply tirea pneumatic tire in which the ply cords that extend to the beads are laid at
substantially 90 degrees to the centerline of the tread
Reinforced tirea tire designed to operate at higher loads and at higher inflation pressures
than the corresponding standard tire
S ec t ion widt hthe linear distance between the exteriors of the sidewalls of an inflated tire,
excluding elevations due to labeling, decoration, or protective bands
Sidewallthat portion of a tire between the tread and bead
Sidewall separationthe 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 Signal Wheel
Driving Traction in a Straight Line on Snow −and Ice −Cov er ed Sur f ac es , and
which is marked with an Alpine Sym bol ( ) on at least one sidewall

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
Ti r e relat ed ter mMeaning
Te s t r i mthe rim on which a tire is fitted for testing, and may be any rim listed as appropri-
ate for use with that tire
Treadthat portion of a tire that comes into contact with the road
Tread riba tread section running circumferentially around a tire
Tread separationpulling away of the tread from the tire carcass
Treadwear indicators (TWI)the projections within the principal grooves designed to give a visual indication
of the degrees of wear of the tread
Wheel−holding fixturethe fixture used to hold the wheel and tire assembly securely during testing
Table 1—Occupant loading and distribution for vehicle normal load for various designated seating capacities
Designated seating capacity,number of occupants
Vehicle normal load, number of occupantsOccupant distribution in a normallyloaded vehicle
2 through 422 in front
5 through 1032 in front, 1 in second seat
11 through 1552 in front, 1 in second seat, 1 in third
seat, 1 in fourth seat
16 through 2072 in front, 2 in second seat, 2 in third
seat, 1 in fourth seat

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2008 SIENNA from Aug. ’08 Prod. (OM45455U)
Determine what kind of tires your
vehicle is originally equipped with.1. Summer tires
Summer tires are high −speed capabil-
ity tires best suited to highway driving
under dry conditions.
Since summer tires do not have the
same traction performance as snow
tires, summer tires are inadequate for
driving on snow −covered or icy roads.
For driving on snow −covered or icy
roads, we recommend using snow
tires. If installing snow tires, be sure
to replace all four tires.
2. All season tires
All season tires are designed to pro-
vide better traction in snow and to be
adequate for driving in most winter
conditions, as well as for use all 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.
The details about how to distinguish
summer tires from all season tires are
described on page 433.
CAUTION

Do not mix summer and all sea-
son tires on your vehicle as
this can cause dangerous han-
dling characteristics, resulting
in loss of control.
 Do not use tires other than the
manufacturer’s designated
tires, and never mix tires or
wheels of the sizes different
from the originally equipped
tires and wheels.
Types of tires