Cadillac 2011 STS Owner's Manual page 415

10. After hearing the confirming single horn chirp for
the driver side rear tire, a double horn chirp will
sound to signal the tire matching mode is no longer
active. Press the push button ignition switch
to Acc.
11. Set all four tires to the recommended air pressure
level as indicated on the tire and loading
information label.
12. Put the valve caps back on the valve stems.
We recommend that you regularly inspect your
vehicle's tires, including the spare tire, for signs of
wear or damage. See
for more information.
Always remove the tires if any of the following
statements are true:
You can see the indicators at three or more
places around the tire.
You can see cord or fabric showing through
the tire's rubber.
The tread or sidewall is cracked, cut,
or snagged deep enough to show cord or
fabric.
The tire has a bump, bulge, or split.
The tire has a puncture, cut, or other damage
that cannot be repaired well because of the
size or location of the damage.
Tire rotation is not recommended if your vehicle
has P235/50ZR18 size tires on the front wheels
and P255/45ZR18 size tires on the rear wheels.
Different tire sizes should not be rotated front to
rear. Each tire and wheel should only be used in
the original front or rear position it is in.
Tire rotation is recommended if the vehicle is
equipped with P235/50R17 size tires on all four
wheel positions or 255/45ZR18 size tires on all
four wheel positions. These tires should be
rotated every 12 000 km (7,500 miles). See
The purpose of a regular tire rotation is to achieve
a uniform wear for all tires on the vehicle. This will
ensure that the vehicle continues to perform most
like it did when the tires were new.
Any time you notice unusual wear, rotate your
tires as soon as possible and check wheel
alignment. Also check for damaged tires or
wheels. See
and
.
.
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