GMC Sierra Classic 2007 Owner's Manual page 506

CAUTION:
{
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
Do not run the engine if there is a leak. If
you run the engine, it could lose all
coolant. That could cause an engine fire,
and you could be burned. Get any leak
fixed before you drive the vehicle.
506
The coolant level should
be at or above the
FULL COLD mark. If it
is not, you may
have a leak at the
pressure cap or in the
radiator hoses,
heater hoses, radiator,
water pump, or
somewhere else in the
cooling system.
If your vehicle has an electric engine cooling fan,
check the coolant temperature gage. If the coolant
temperature is approximately 232°F (111°C), the
electric cooling fan should be running. If it is not,
your vehicle needs service. Turn off the engine.
If your vehicle has an engine-driven cooling fan,
start the engine again and see if the fan speed
increases when idle speed is doubled by pushing
the accelerator pedal down. If it does not, your
vehicle needs service. Turn off the engine.
Notice: Engine damage from running your
engine without coolant is not covered by your
warranty. See Overheated Engine Protection
Operating Mode (V8 Engines Only) on page 504
for information on driving to a safe place in
an emergency.
Notice: Using coolant other than DEX-COOL
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant could require changing sooner, at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Any repairs would not
be covered by your warranty. Always use
®
DEX-COOL (silicate-free) coolant in your
vehicle.
®