Coolant Surge Tank Pressure Cap; Engine Overheating - GMC Sierra Denali Owner's Manual

Coolant Surge Tank Pressure Cap
The coolant surge tank
pressure cap must be fully
installed on the coolant
surge tank.
Nofice: Your pressure cap is a pressure-type cap
and must be tightly installed to prevent coolant loss
and possible engine damage from overheating.
See "Capacities and Specifications" for more
information.
Engine Overheating
You will find a coolant temperature gage on your
vehicle's instrument panel. See Engine Coolant
Temperature Gage
on
page 3-36. In addition, you will
find a LOW COOLANT, ENGINE OVERHEATED and a
REDUCED ENGINE POWER message in the DIC on
the instrument panel. See Driver lnformation Center
(DIC) on page 3-43.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternates firing groups
of cylinders helps prevent engine damage. In this mode,
you will notice a loss in power and engine performance.
This operating mode allows your vehicle to be driven to
a
safe place in an emergency. Driving extended miles (km)
and/or towing a trailer in the overheat protection mode
should be avoided.
Nofice: After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any re
The engine oil will be severely degraded. Repair the
cause of coolant
loss,
change the oil and reset the oi
life system. See "Engine Oil" in the Index.
5-27