Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -2016 - crc - 11/6/15Vehicle Care 279{ WarningSteam and scalding liquids from ahot cooling system can blow outand burn you badly. Never turnthe cap when the cooling system,including the surge tank pressurecap, is hot. Wait for the coolingsystem and surge tank pressurecap to cool.{ WarningAdding only plain water or someother liquid to the cooling systemcan be dangerous. Plain waterand other liquids, can boil beforethe proper coolant mixture will.The coolant warning system is setfor the proper coolant mixture.With plain water or the wrongmixture, the engine could get toohot but you would not get theoverheat warning. The enginecould catch fire and you or others(Continued)Warning (Continued)could be burned. Use a 50/50 mixture of clean, drinkablewater and DEX-COOL coolant.CautionIn cold weather, water can freezeand crack the engine, radiator,heater core, and other parts. Usethe recommended coolant andthe proper coolant mixture.{ WarningYou can be burned if you spillcoolant on hot engine parts.Coolant contains ethylene glycoland it will burn if the engine partsare hot enough. Do not spillcoolant on a hot engine.1. Remove the coolant surge tankpressure cap when the coolingsystem, including the coolantsurge tank pressure cap andupper radiator hose, is nolonger hot.Turn the pressure cap slowlycounterclockwise aboutone-quarter of a turn. If youhear a hiss, wait for that tostop. This will allow anypressure still left to be ventedout the discharge hose.2. Keep turning the pressure capslowly and remove it.3. Fill the coolant surge tank withthe proper mixture to theindicated level mark.4. With the coolant surge tankpressure cap off, start theengine and let it run until youcan feel the upper radiatorhose getting hot. Watch out forthe engine cooling fan.By this time, the coolant levelinside the coolant surge tankmay be lower. If the level islower, add more of the propermixture to the coolant surgetank until the level reaches theindicated level mark.
