Pontiac 2003 Bonneville Owner's Manual page 322

See the example below. When you end this high-speed
driving, return to the cold inflation pressure shown on
the Tire-Loading Information label.
Example:
You'll find maximum load and inflation pressure molded
on the tire's sidewall, in small letters near the rim
flange. It will read something like this: Maximum load
690 kg (1521 Ibs) @ 300 kPa (44 psi) Max. Press.
For this example, you would set the inflation pressure
for high-speed driving at 35 psi (244 kPa).
Notice:
Don't let anyone tell you that underinflation
or overinflation is all right. It's not. If your tires
don't have enough air (underinflation), you can get
the following:
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy
If your tires have too much air (overinflation), you
can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Don't forget your compact spare tire. It should be at
60 psi (420 kPa).
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can't tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they're underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks
by
keenin9 out
dirt and
moisture.
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