2001 Cadillac Eldorado Owner's Manual - Page 278

NOTICE: If you use an improper coolant mixture, your engine could overheat and be badly damaged. The repair cost wouldn't be covered by your warranty. Too much water in the mixture can freeze and crack the engine, radiator, heater core and other parts. If you have to add coolant more than four times a year, have your dealer check your cooling system. Checking Coolant NOTICE: If you use the proper coolant, you don't have to add extra inhibitors or additives which claim to improve the system. These can be harmful. The surge tank is located next to the engine block on the passenger's side of the engine. For more information on location, see "Engine Compartment Overview" in the Index. 6-24