1996 Mercury Cougar Owner's Manual - Page 244

Ford Premium Cooling System Fluid is an optimized formula that will protect all metals and rubber elastomers used in Ford engines for four years or 50,000 miles (80,000 km). It is not necessary and not recommended to use supplemental coolant additives in your gasoline powered vehicle. These additives may harm your engine cooling system. Follow the recommended service interval for changing your engine coolant. NOTE: When you change or add engine coolant, it is important to maintain your engine coolant concentration between 40% (-11˚F [-24˚C]) and 60% (-62˚F [-52˚C]), depending on your local climate conditions. Below 40% you will lose freeze protection and above 60% your engine may overheat on a warm day. NOTE: The use of an improper coolant may void your warranty for the engine cooling system. Use only a premium nationally recognized brand name engine coolant. Do not use alcohol, methanol antifreeze or engine coolant mixed with alcohol or methanol antifreeze. If you do not use the proper coolant, the aluminum radiator on your vehicle will corrode. Ford Motor Company expressly authorizes the Ford Rotunda engine coolant recycling process and chemicals. Use only Ford Rotunda recycled engine coolant or an equivalent recycled engine coolant that is certified by the supplier to meet Ford specification ESE-M97B44-A. 247