1994 Buick Regal Owner's Manual - Page 225

Engine Coolant The following explains your cooling system and how to add coolantwhen it is low. If you have a problem with engine overheating or you need to add coolant to your if radiator, see "Engine Overheating" in the Index. The proper coolantfor your Buick will: 0 0 Give freezing protection down to -34°F (-37°C). Give boiling protection up to 262°F (128°C). Protect against rust and corrosion. Help keep the proper engine temperature. Let the warning lights work as they should. 0 What to Use Use a mixture of one-half clean water (preferably distilled) and one-half antifreeze that meets "GM Specification 1825-M," which won't damage aluminum parts. You can also usea recycled coolant conforming to GM Specification 1825-M with a complete coolant flush and refill. If you use this mixture, you don't needadd to anything else. NOTICE: If you use an improper coolant mix, your engine could overheat and be badly damaged. The repair cost wouldn't be covered by your warranty. Too much water in the mix can freeze 'and crack the engine, radiator, heater core and other parts. 223