GMC 2010 Sierra 1500 Crew Cab Owner's Manual page 269

For vehicles with an engine oil pressure gauge, it shows
the engine oil pressure in psi (pounds per square inch)
when the engine is running. Canadian vehicles indicate
pressure in kPa (kilopascals).
Oil pressure can vary with engine speed, outside
temperature and oil viscosity, but if readings are outside
the normal operating range, the oil pressure light comes
on. See
information.
A reading outside the normal operating range can be
caused by a dangerously low oil level or some other
problem causing low oil pressure. Check the vehicle's
oil as soon as possible. See OIL PRESSURE LOW
under
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
for more
.
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