How often should antifreeze be changed?
2 Answers
For ordinary family cars, it is generally recommended to change the antifreeze every two years or 40,000 kilometers, depending on actual usage. If the vehicle is used intensively, it may need to be replaced earlier. The engine and its cooling system are made of metals such as copper, iron, aluminum, steel, and solder. Over time, these metals can corrode and rust when exposed to water under high temperatures. Antifreeze not only prevents corrosion in the engine cooling system but also has anti-corrosion and rust-removal functions. The full name of antifreeze should be 'antifreeze coolant,' meaning a coolant with antifreeze properties. Antifreeze prevents the coolant from freezing in cold winter conditions, which could otherwise cause the radiator to crack or damage the engine cylinder block or head. Antifreeze is not just for winter use—it should be used year-round.
I've found that the frequency of coolant replacement varies by vehicle, typically every two years or around 50,000 kilometers is recommended. I usually refer to the vehicle manual's suggestions, as requirements differ between models—some newer cars use long-life coolant that can last five years or more. Coolant doesn't just prevent freezing; it also protects the engine from overheating and reduces corrosion. If left unchanged for too long, it degrades, accumulates deposits, and can clog the radiator or damage the engine, leading to repair costs far exceeding a coolant change. I make it a habit to check the coolant level every season when the engine is cold, ensuring it's within the normal range. If the color turns cloudy or shows impurities, it's a sign to replace it. I also use simple test strips to check pH and concentration, confirming its protective state. In short, regular replacement not only saves fuel but also extends engine life, avoiding the embarrassment of a roadside breakdown.