2006 GMC Envoy Owner's Manual - Page 383

Adding Coolant If you need more coolant, add the proper DEX-COOL coolant mixture at the coolant recovery tank. ® Add coolant mixture at the recovery tank, but be careful not to spill it. {CAUTION: {CAUTION: Turning the radiator pressure cap when the engine and radiator are hot can allow steam and scalding liquids to blow out and burn you badly. With the coolant recovery tank, you will almost never have to add coolant at the radiator. Never turn the radiator pressure cap - even a little - when the engine and radiator are hot. You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol, and it will burn if the engine parts are hot enough. Do not spill coolant on a hot engine. Occasionally check the coolant level in the radiator. For information on how to add coolant to the radiator, see Cooling System on page 5-30. 5-27