Chevrolet TrailBlazer 2007 Owner's Manual page 417

5.3L V8 Engine shown, 6.0L V8 Engine similar
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan
If the coolant inside the coolant recovery tank is
boiling, do not do anything else until it cools down.
The vehicle should be parked on a level surface.
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.
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.
417