GMC 2007 Acadia - Manual (Page 414)

When the engine is cold, the coolant level should
be at least up to 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.
{ 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.
If there seems to be no leak, with the engine on,
check to see if the electric engine cooling fans are
running. If the engine is overheating, both fans
should be running. If they are not, your vehicle
needs service.
Notice: Engine damage from running your
engine without coolant is not covered by your
warranty.
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.
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