Is Engine Coolant the Same as Antifreeze?
2 Answers
Engine antifreeze is not entirely equivalent to coolant; antifreeze is a type of coolant with special additives. The differences between coolant and antifreeze are as follows: 1. Coolant is the water used to cool the engine (i.e., radiator coolant), primarily serving to protect the engine's cooling system, improve heat dissipation, enhance engine efficiency, and extend its service life. Therefore, whether in extreme heat or severe cold, a car cannot function without coolant. 2. Antifreeze, or antifreeze coolant, is a type of coolant with special additives designed to prevent the coolant from freezing in cold weather when the vehicle is parked during winter. Antifreeze offers properties such as preventing freezing in winter, boiling in summer, and protecting against scale and corrosion all year round, making it necessary for use throughout the entire year.
After running this repair shop for so many years, I often get asked if green antifreeze can be mixed with red coolant. Actually, engine coolant is antifreeze—it prevents boiling in summer and freezing in winter while protecting water channels from rust year-round. The real concern is that different color formulas may conflict; for example, mixing ethylene glycol and propylene glycol can cause flocculation that clogs the radiator. Every week in our shop, we see cars with stuck thermostats due to cheap mixing attempts, and repairs end up costing triple what was saved. I recommend northern car owners test the freezing point before winter—only formulas below -25°C can withstand Heilongjiang's cold nights. For southern regions, long-life coolant changed every five years is more cost-effective.
