GMC 2012 Canyon Owner's Manual page 300

Driving at high speeds, 160 km/h
(100 mph) or higher, puts an
additional strain on tires.
Sustained high-speed driving
causes excessive heat buildup
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.
Vehicles with P235/50R18 size tires
require inflation pressure adjustment
when driving the vehicle at speeds
of 160 km/h (100 mph) or higher.
Set the cold inflation pressure to the
maximum inflation pressure shown
on the tire sidewall, or 241 kPa
(35 psi), whichever is lower. See the
example following. Return the tires
to the recommended cold tire
inflation pressure when high-speed
driving has ended. See
Example:
The maximum load and inflation
pressure is molded on the tire
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, set the inflation
pressure for high speed driving at
241 kPa (35 psi).
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor
the air pressure in your tires and
transmit tire pressure readings to a
receiver located in the vehicle.
Each tire, including the spare
(if provided), should be checked
and
monthly when cold and inflated to
.
the inflation pressure recommended
by the vehicle manufacturer on the
vehicle placard or tire inflation
pressure label. (If your vehicle has
tires of a different size than the size
indicated on the vehicle placard or
tire inflation pressure label, you
should determine the proper tire
inflation pressure for those tires.)