GMC 2007 Envoy - Manual (Page 411)

Cooling System
When you decide it is safe to lift the hood, here is
what you will see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan
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.
4.2L L6 Engine
5.3L V8 Engine
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