Saturn 2009 ASTRA - Manual (Page 232)

When to Check
Check your tires once a month
or more. Do not forget to
check the compact spare tire,
it should be at 60 psi (420 kPa).
For additional information
regarding the compact spare
tire, see Compact Spare Tire
on page 9-68.
How to Check
Use a good quality pocket-type
gage to check tire pressure.
You cannot tell if your tires are
properly inflated simply by
looking at them. Radial tires
may look properly inflated even
when they are under-inflated.
Check the tire’s inflation
pressure when the tires are
cold. Cold means your vehicle
has been sitting for at least
three hours or driven no more
than 1 mile (1.6 km).
Remove the valve cap from
the tire valve stem. Press the tire
gage firmly onto the valve to
get a pressure measurement.
If the cold tire inflation pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the inflation pressure is low,
add air until you reach the
recommended amount.
If you overfill the tire, release air
by pushing on the metal stem
in the center of the tire valve.
Re-check the tire pressure with
the tire gage.
Be sure to put the valve caps
back on the valve stems.
They help prevent leaks by
keeping out dirt and moisture.
High-Speed Operation
{ CAUTION
Driving at high speeds, 100 mph
(160 km/h) or higher, puts an
additional strain on tires.
Sustained high-speed driving
causes excessive heat build up
and can cause sudden tire failure.
You could have a crash and
you or others could be killed.
Some high-speed rated tires
require inflation pressure
adjustment for high speed
operation. When speed limits and
road conditions are such that a
vehicle can be driven at high
speeds, make sure the tires are
rated for high speed operation, in
excellent condition, and set to the
correct cold tire inflation pressure
for the vehicle load.
9-48 Vehicle Service and Care