Cadillac 1999 DeVille Owner's Manual page 314

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 lbs.) @ 300 kPa (44 psi) Max. Press.
For this example, you would set the inflation pressure
-
for high speed driving at 38 psi (265 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:
D
Too much flexing
D
Too much heat
D
Tire overloading
D
Bad wear
D
Bad handling
D
Bad fuel economy.
6-44
NOTICE: (Continued)
NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:
D
Unusual wear
D
Bad handling
D
Rough ride
D
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
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 keeping out dirt
and moisture.
-
type gage to check tire
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