2015 Buick Regal Owner Manual - Page 267

10-20 Vehicle Care Caution (Continued) proper mixture of engine coolant for the cooling system. See Recommended Fluids and Lubricants on page 11-12. Never dispose of engine coolant by putting it in the trash, pouring it on the ground, or into sewers, streams, or bodies of water. Have the coolant changed by an authorized service center, familiar with legal requirements regarding used coolant disposal. This will help protect the environment and your health. If coolant is visible but the coolant level is not at or above the mark pointed to, add a 50/50 mixture of clean drinkable water and DEX-COOL coolant. Be sure the cooling system is cool before this is done. If no coolant is visible in the coolant surge tank, add coolant as follows: This mixture: . 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. . . . . How to Add Coolant to the Coolant Surge Tank { Caution If improper coolant mixture, inhibitors, or additives are used in the vehicle cooling system, the engine could overheat and be damaged. Too much water in the mixture can freeze and crack engine cooling parts. The repairs would not be covered by the vehicle warranty. Use only the (Continued) { Caution This vehicle has a specific coolant fill procedure. Failure to follow this procedure could cause the engine to overheat and be severely damaged. If no problem is found, check to see if coolant is visible in the coolant surge tank. If coolant is visible but the coolant level is not at the indicated level mark, add a 50/50 mixture of clean, drinkable Checking Coolant The vehicle must be on a level surface when checking the coolant level. Check to see if coolant is visible in the coolant surge tank. If the coolant inside the coolant surge tank is boiling, do not do anything else until it cools down.