2003 Pontiac Grand Prix Owner's Manual - Page 256

Checking Coolant water or e coo I t n ture. wrongmixture, your engine could get too hot but you wouldn'tget the overheat warning. Your engine could catch fire and you or others could be burned. Use a 50/50 mixture of clean, drinkable water and DEX-COOL@coolant. The coolant recovery tank is located in the engine compartment toward the rear of the engine on the passenger's side of the vehicle. See Engine Compartment Overview on page5-12 for more information on location. The vehicle must be on a level surface. When your engine is cold, the coolant level should be at the COLD mark or a little higher. When your engine is warm, the level should be up to the HOT mark or a little higher. Notice: If you use an improper coolant mixture, your engine could overheat and be badlydamaged. 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. 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. When your engine is warm, the level should be up to the HOT mark or a little higher. 5-31