1995 Oldsmobile Silhouette Owner's Manual - Page 241

How to Add Coolant to the Coolant Recovery Tank If you haven't found a problem yet, the coolant but level isn't at or above the FULL HOT mark, add a 50/50 mixture of clean water (preferably distilled)and a proper antifreeze at the coolant recovery tank. (See "Engine Coolant" in the Index for information more about the proper coolant mix.) NOTICE: In cold weather, water can freeze and crack the engine, radiator, heater core and other parts. Use the recommended coolant. When the coolant in the coolant recovery tank is at or above the FULL HOT mark, start your vehicle. If the overheat warning continues, there's one more thing you can try. You can add the proper coolantmix directly to the radiator, but be sure the cooling system is cool before you do it. 5-19