antifreeze

According to the owners manual: "Use a mixture of one-half clean water (preferably distilled) and one-half DEX-COOL@ coolant which won't damage aluminum parts. And the cooling system capacity including the reservoir is 10.2 qts." I don't know which brand names coolants are the equivalent of Dex-Cool. If your car didn't have a manual or it got lost somewhere along the long road of life, you can download one free here: http://www.autousermanual.com/view/oldsmobile/intrigue/ I hope this helps.