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2005 SIENNA from Sep. ’04 Prod. (OM45431U)
Tire pressure gauge
INSPECTION AND ADJUSTMENT
PROCEDURE 1. Remove the tire valve cap.
2. Press the tip of the tire pressure gauge to the tire valve.
3. Read the pressure using the grad- uations of the gauge.
4. In case the tire inflation pressure
is not within the prescribed range,
insert the compressed air from the
valve. In case of applying too
much air, press the center of the
valve and release the air to adjust. 5. After completing the tire inflation
pressure measurement and ad-
justment, apply soapy water to the
valve and check for leakage.
6. Install the tire valve cap.
If a gauge and air pump are not avail-
able, have your vehicle checked by
your Toyota dealer.
CAUTION
Be sure to reinstall the tire valve
caps. Without the valve caps, dirt
or moisture could get into the
valve core and cause air leakage.
If the caps have been lost, have
new ones put on as soon as pos-
sible.
Incorrect tire infl ation pressure may
waste fuel, reduce the comfort of driv-
ing, reduce tire life and make your ve-
hicle less safe to drive.
If a tire frequently needs refilling,
have it checked by your Toyota deal-
er.
CAUTION
Keep your tires properly inflated.
Otherwise, the following condi-
tions may occur and cause an ac-
cident resulting in death or seri-
ous injuries.
Low tire pressure ( underinfla-
tion)—
Excessive wear
Uneven wear
Poor handling
Possibility of blowouts from an
overheated tire
Poor sealing of the tire bead
Wheel deformation and/or tire
separation
A greater possibility of tire
damage from road hazards
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High tire pressure (overinfla-
tion)—
Poor handling
Excessive wear
Uneven wear
A greater possibility of tire
damage from road hazardsTread wear indicator
CHECKING YOUR TIRES
Check the tire’s tread for tread
wear indicators. If the indicators
show, replace the tires. The loca-
tion of tread wear indicators is
shown by the “TWI” or “
Δ” marks,
etc., molded on the sidewall of
each tire. The tires on your Toyota have built
−in
tread wear indicators to help you
know when the tires need replace-
ment. When the tread depth wears to
1.6 mm (0.06 in.) or less, the indica-
tors will appear. If you can see the
indicators in two or more adjacent
grooves, the tire should be replaced.
The lower the tread, the higher the
risk of skidding.
The effectiveness of snow tires is
lost if the tread wears down below
4 mm (0.16 in.).
If you have tire damage such as
cuts, splits, cracks deep e nough to
expose the fabric, or bulges indi-
cating internal damage, the tire
should be repl aced.
If a tire often goes flat or cannot be
properly repaired due to the size or
location of a cut or other damage, it
should be replaced. If you are not
sure, consult with your Toyota dealer.
Checking and replacing tires
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If air loss occurs while driving, do not
continue driving. Driving even a short
distance can damage a tire beyond
repair.
An y ti res wh i ch are over 6 years
old must be checked by a qualified
technician even if damage is not
obvious.
Tires deteriorate with age even if they
have never or seldom been used.
This applies also to the spare tire and
tires stored for future use.
REPLACING YOUR TIRES
When replacing a tire, use a tire of
the same size and construction,
and the same or greater maximum
load as the originally installed
tires. Also, on all wheel drive mod-
els, all the tires must be the same
brand and have the same tread pat-
terns.Using any other size or type of tire
may seriously affect handling, ride,
speedometer/odometer calibration,
ground clearance, and clearance be-
tween the body and tires or snow
chains.
Check that the maximum load of the
replaced 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. As for the
maximum load of the tire, see the load
limit at maximum cold tire inflation
pressure mentioned on the sidewall
of the tire, and as for the Gross Axle
Weight Ratings (GAWR), see the Cer-
tification Label.
For details about the side wall of the
tire and the Certification Label, see
pages 386 and 388.
CAUTION
Observe the following instruc-
tions. Otherwise, an accident
may occur resulting in death or
serious injuries.
Do not mix radial, bias belted,
or bias ply tires on your ve-
hicle, as this may cause dan-
gerous handling characteris-
tics resulting in loss of control.
Do not use tires other than the
manufacturer’s recommended
size, as this may cause danger-
ous handling characteristics
resulting in loss of control.
All wheel drive models:
Do not use tires of different
brands, sizes, construction or
tread patterns, as this may
cause dangerous handling
characteristics resulting in
loss of control.
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Toyota recommends all four tires,
or at least both of the front or rear
tires be replaced at a time as a set.
See “If you have a flat tire” on page
421 in Section 4 for tire change proce-
dure.
When a tire is replaced, the wheel
should always be balanced.
An unbalanced wheel may affect ve-
hicle handling and tire life. Wheels
can get out of balance with regular
use and should therefore be balanced
occasionally.
When replacing a tubeless tire, the
air valve should also be replaced
w i t h a new on e.
Initial adjustment of the tire pres-
sure warning system is necessary
after you have rotated your tires.
See “Tire pressure warning sys-
tem” on page 196 in Section 1 7.
To equalize the wear and help ex-
tend tire life, Toyota recommends
that you rotate your tires accord-
ing to the maintenance schedule.
(For scheduled maintenance infor-
mation, please refer to the “Sched-
uled Maintenance Guide” or “Own-
er’s Manual Supplement”.)
However, the most appropriate tim-
ing for tire rotation may vary ac-
cording to your driving habits and
road surface conditions.
See “If you have a flat tire” on page
421 in Section 4 for tire change proce-
dure. When rotating tires, check for uneven
wear and damage. Abnormal wear is
usually caused by incorrect tire pres-
sure, improper wheel alignment, out
−
of −balance wheels, or severe braking.
CAUTION
Do not include a compact spare
tire when rotating the tires. It is
designed for temporary use only.
Initial adjustment of the tire pres-
sure warning system is necessary
after you have rotated your tires.
See “Tire pressure warning sys-
tem” on page 196 in Section 1 7.
Rotating tires
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