What Are the Main Components of Automotive Antifreeze?
2 Answers
Antifreeze is mainly composed of 50% pure water, 40% methanol, and 10% other substances. Functions of Antifreeze: Antifreeze is a coolant containing special additives, primarily used in liquid-cooled engine cooling systems. It offers excellent performance in preventing freezing in winter, boiling in summer, and resisting scale and corrosion year-round. Antifreeze Replacement Cycle: For vehicles that operate for long periods, such as taxis, high-quality antifreeze should generally be replaced annually. For vehicles with shorter operating times, replacement can be done every two years or every 30,000 kilometers. To avoid excessive foam formation, which reduces the heat exchange efficiency between the antifreeze and engine components, ensure the product is within its validity period when adding it. Long-life antifreeze can remain effective for up to three years. If suspended particles, sediment, or signs of deterioration or discoloration are observed in the antifreeze, it should be replaced promptly, and the system should be cleaned. Can Different Antifreeze Brands Be Mixed? It is necessary to use the same brand of antifreeze. Different brands may have varying production formulas, and mixing them could lead to chemical reactions between additives, rendering them ineffective.
I've been running an auto repair shop for over a decade. The main components of antifreeze are actually ethylene glycol and water, accounting for about 95%. Ethylene glycol is quite amazing—it won't freeze even at minus 30-40 degrees Celsius and can withstand temperatures over 100 degrees Celsius in summer, making it super effective for engine protection. The remaining 5% is the secret formula that manufacturers keep confidential, mainly consisting of additives like corrosion inhibitors and anti-foaming agents. Corrosion inhibitors prevent rust in the pipes, while anti-foaming agents stop bubbles from forming during high-speed coolant circulation. By the way, there are now eco-friendly antifreeze options that use propylene glycol instead of ethylene glycol—they're more expensive but significantly less toxic. Every time I change antifreeze for customers, I always remind them: never cut corners by mixing it with tap water to save money, as the mineral deposits can clog the radiator.
