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Dear James, My dealership says that I must use their type antifreeze in my vehicle. Isn’t there universal type antifreeze I can use in my car? I read your column every week and I have not read anything about using the right type antifreeze. I know that years past antifreeze was green now it is every color of the rainbow. How come they changed from green to different colors? Joe in Panama.

Dear Panama Joe, The easiest part of your question about why they changed colors of the antifreeze. It was to let people know it is a different KIND of antifreeze. If you see a color fluid you’re not familiar with it may make you step back and think about just adding just any other color antifreeze to it. The difference between green antifreeze and the other color antifreeze is they are not silica based (like your old green antifreeze). They are now called (Organic Acid Technology) or OAT antifreeze or HOAT (Hybrid Organic Acid Technology) Silica is a hard glassy mineral such as sand or quartz that coats your cars metal like paint. Your water pump seals and your engine gaskets were designed for this type antifreeze on older model cars. Years ago we had brass/copper radiators that were very large and forgiving to abuse and neglect. Car engines were heavy duty and we had lots of cast iron and steel. Silica based antifreeze did a great job of getting rid of heat and keeping chemical corrosion down to a minimum. Of course you had to change it every two years or 30,000 miles or it would slowly destroy your cars cooling system with scale, rust and corrosion not to mention electrolysis eating away at the metal. Now here comes the mid 90’s and orange, blue, red and straw colored antifreeze appear in these newer cars. People believed the new car salesman that told you could go 5 years or 150,000 miles on this new “improved antifreeze”. So most people followed their advice and around 75,000 to 100,000 miles (when their new car warranty had expired) they had to replace their intake gaskets or their water pumps and radiators. Class action lawsuits were filed and car companies lost money helping to pave there downhill financial slide. What the car companies realized customers and shops were adding water to the antifreeze that was not distilled water. If so, the radiator would clog up with rust and sludge causing a problem. And if the customer did not change the antifreeze every two years or 30,000 miles it would slowly dissolve the plastic intake gaskets made of nylon 6.6, causing the coolant to leak out. This new Organic Acid Technology antifreeze was great to the metal parts in the engine. It chemically “blued” the metal like you would a firearm. It did a better job of protecting the metal in an engine over the old silica based green antifreeze which just coated the metal. The bad part is about this OAT/HOAT coolant will dissolve plastic intakes and gaskets and water pump impellors as well as radiator tanks if left too long in your car cooling system without being changed. So to answer your most important question: Do they make universal antifreeze for today’s cars? No, there is no such antifreeze sitting on the auto parts store shelf. That is why they have so many brands for you to choose from. You must use antifreeze that is compatible with your cars cooling system. If not, a few thousand miles down the road you will remember this letter when you have to change your water pump or head gasket or worse yet, replace your engine.


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