Toyota 2006 Prius Owner's Manual page 425

If air loss occurs while driving, do not
continue driving. Driving even a short
distance can damage a tire beyond
repair.
Any tires which 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.
408
REPLACING YOUR TIRES
When replacing a tire, use a tire of
the same size and construction,
and the same or greater load ca-
pacity as the originally installed
tires.
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
sidewall of the tire and the Certifica-
tion Label, see pages 332 and 330.
CAUTION
Observe the following instruc-
tions. Otherwise, an accident
may occur resulting in death or
serious injuries.
D 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.
D Do not use tires other than the
manufacturer's recommended
size, as this may cause danger-
ous handling characteristics
resulting in loss of control.
Toyota recommends all four tires,
or at least both front or rear tires
be replaced at a time as a set.
See "If you have a flat tire" on page
361 for tire change procedure.