2012 Buick LaCrosse Owner Manual - Page 354

10-16 Vehicle Care What to Use Use a 50/50 mixture of deionized water or clean, drinkable water and DEX-COOL coolant. If using this mixture, nothing else needs to be added. This mixture: . Engine Coolant The cooling system in the vehicle is filled with DEX-COOL® engine coolant mixture. See Recommended Fluids and Lubricants on page 11‑12 and Maintenance Schedule on page 11‑3 for more information. The following explains the cooling system and how to check and add coolant when it is low. If there is a problem with engine overheating, see Engine Overheating on page 10‑19. { WARNING Adding only plain water or some other liquid to the cooling system can be dangerous. Plain water and other liquids can boil before the proper coolant mixture will. The coolant warning system is set for the proper coolant mixture. With plain water or the wrong mixture, the engine could get too hot but you would not get the overheat warning. The engine could catch fire and you or others could be burned. Use a 50/50 mixture of clean, drinkable water and DEX-COOL coolant for non-eAssist engine(s). Use a 50/50 mixture of deionized water and DEX-COOL coolant for eAssist engine(s). Gives freezing protection down to −37°C (−34°F), outside temperature. Gives boiling protection up to 129°C (265°F), engine temperature. Protects against rust and corrosion. Will not damage aluminum parts. Helps keep the proper engine temperature. . . . .