Chevrolet SS Sedan 2015 Owner's Manual page 336

How to Check
Use a good quality pocket-type
gauge to check the tire
pressure. Proper tire inflation
cannot be determined by looking
at the tire. Check the tire
inflation pressure when the tires
are cold, meaning the vehicle
has not been driven for at least
three hours or no more than
1.6 km (1 mi).
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to
get the 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 the recommended
pressure is reached. If the
inflation pressure in high, press
on the metal stem in the center
of the tire valve to release air.
Re-check the tire pressure with
the tire gauge.
Return the valve caps on the
valve stems to keep out dirt and
moisture and prevent leaks.
Tire Pressure for
High-Speed Operation
Warning
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
Warning (Continued)
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 245/40ZR19 98Y and
275/35ZR19 100Y tires are capable
of high speed use.
Make sure front tires of size 245/
40ZR19 98Y are inflated to 310 kPa
(45 psi) before operating the vehicle
at speeds of 160 km/h (100 mph) or
higher.
Make sure rear tires of size 275/
35ZR19 100Y are inflated to
340 kPa (50 psi) before operating
the vehicle at speeds of 160 km/h
(100 mph) or higher.
Return the tires to the
recommended cold tire inflation
pressure when high-speed driving
(Continued)
Vehicle Care 10-43