1996 GMC Jimmy Owner's Manual - Page 226

How to Add Coolant to the Coolant Recovery Tank If you haven't found a problem yet, but the coolant level isn't at the ADD mark, add a 50/50 mixture of clean wcrter (preferably distilled)and DEX-COOL (orange-colored, silicate-free) antifreezeat the coolant recovery tank. (See "Engine Coolant'' in the Index for more information.) TM I NOTICE: In cold weather, water can freeze and crack the engine, radiator, heater core and other parts. Use the recommended coolant and the proper coolant mix. I Adding only plain water to your cooling system can be dangerous. Plain water, some other or liquid like alcohol, can boil before the proper coolant mix will. Your vehicle's coolant warning system is set for the proper coolant With mix. plain water or the wrong your engine could mix, get too hot but you wouldn't get the overheat warning. Your engine could catch fire and or you others could be burned. a 50/50 mix of clean Use water and DEX-COOL TM antifreeze. 5-15