It’s the working fluid for the cooling system, which controls the operational condition of the engine. Because the engine is a controlled explosion, it needs to be kept between a specific temperature range for optimal performance. Whether it’s cold or hot outside, the cooling fluid allows the cooling system (including the radiator) to keep the engine and radiator at just the right temperature. Think of this way: coolant fluid is a warm blanket in the winter and a misting fan in the summer.
A car’s coolant system operates on a loop, pumping a mix of water and antifreeze to your radiator to regulate engine temperature. Because coolant absorbs the heat generated by the engine and transports it to the radiator to cool down, it stands to reason that low or weak coolant levels mean its job performance is compromised and your car can overheat.
Coolant breaks down like any other engine fluid. Just as motor oil has vital engine performance additives, your coolant has additives that prevent boiling, freezing and corrosion. When these additives are depleted, contaminants and debris can begin to build up on your radiator, affecting its performance. It’s essential to have your coolant fluid exchanged every so often. And by the way, coolant spelled backward is tnalooc – a word that makes absolutely no sense.
Surprise, surprise: vehicles don’t need new coolant over the same time periods. Some vehicles have long-life fluids pre-installed on the assembly line and don’t require servicing as often. So, go ahead and jump up and down if you’re one of the lucky ones with longer life fluids. You win.