2004 Cadillac Escalade EXT Owner's Manual - Page 334

Cooling System When you decide it's safe to lift the hood, here's what you'll see: If the coolant inside the coolant surge tank is boiling, don't do anything else until it cools down. The vehicle should be parked on a level surface. The coolant level should be at or above the FULL COLD mark. If it isn't, 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. A. Coolant Surge Tank B. Coolant Surge Tank Pressure Cap C. Engine Fan 5-28