1996 Pontiac Trans Sport Owner's Manual - Page 237

How to Add Coolant to theCoolant Recovery Tank If you haven't found a problem yet, but the coolant level isn't at or above the FULL HOT mark, add a 50/50 mixture of clean water (preferably distilled) and DEX-COOL TM (orange-colored, silicate-free) antifreeze at thecoolant recovery tank. (See "EngineCoolant" in the Index for more information.) plain water or the wrong mix,your engine could get toohot but you wouldn't get overheat the warning. Your engine could catch fire andyou o'r others could beburned. Use a 50/50 mix of clean water and DEX-COOL antifreeze. NOTICE: ~ ~ Adding onlyplain water to your cooling system can be dangerous.Plain water, or some other liquid like alcohol, can boil before the proper coolant mix will. Your vehicle's coolant warning system isset for the proper coolant mix. With CAUTION: (Continued) In cold weather,water can freeze and crack the engine, radiator, heatercore and otherparts. Use the recommended coolant and the proper coolant mix. 5-17 I