1995 Buick Roadmaster Owner's Manual - Page 233

Engine CooIant The following explains yo& cooling system how to and add coolant when is low. If youhave a problem with it engine overheating,see "Engine Overheating"in the Index. The proper coolafitfor your Buick will: Give freezing protection down to-340 F (-37" C). Give boiling protection up to 262'" (128 C . F ) O Protect against rust and corrosion. 0 0 Help keep the proper engine temperature. Let the warning lights work as they should. 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 use a recycled coolant conforming to GM Specification 1825-M with a complete coolant flush and refill. Use GM Engine Coolant Supplement (sealer) with any complete coolantflush and refill.If you use this mixture, you don't need to add 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 waterin the mix can freeze and crack the engine, radiator, heater core and other parts. 6-17