The changing colors of coolant. It used to be quite simple, coolant was green. Now there is green, dark green, orange, pink, yellow, red and even blue. What does it all mean? That’s a good question since there isn’t really a standardization yet. The green is still the same ethylene glycol but the others are propylene glycol with either organic or inorganic acid technology. The acid technology is designed to inhibit the electrolysis and corrosion of aluminum, since most newer cars are using aluminum core heaters, radiators, water pumps, not to mention, aluminum heads and blocks are more common as well.

Here is a technical service bulletin about the changing colors of coolant – TSB in PDF format

Auto Outlet can determine what coolant is best for your vehicle and perform any cooling system service or repair. Auto Outlet stocks the common coolants but can order whatever your vehicle needs.

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