Should Antifreeze Be Replaced in Winter?
4 Answers
Antifreeze replacement is not season-dependent, meaning it doesn't matter whether it's summer or winter. For vehicles that run for long hours, such as taxis, high-quality antifreeze generally needs to be replaced once a year. For vehicles with shorter operating times, replacement can be done every two years or every 30,000 kilometers. How to Replace Antifreeze: Before completely replacing the antifreeze, conduct a thorough inspection to check for any signs of leaks or cracks in the pipelines, with a special focus on the five-way water pipe. Antifreeze is distributed to different parts of the car through the five-way pipe to perform its function. If there are any signs of antifreeze leakage in this part, replace the water pipe or resecure the connection as needed. Drain the old antifreeze, then flush the liquid channels with clean water. Add clean water to the antifreeze reservoir and continue filling until water continuously flows through the engine cooling system. Then, start the engine and let it idle for 3 to 5 minutes to circulate the water. The water initially flowing out from the reservoir will have a faint pink tint. Continue adding clean water until the outflow is clear. Don’t forget to remove the heater hose and drain the water from the heater core. About an hour after draining, add new antifreeze through the radiator hose. Then, pour another container of antifreeze into the antifreeze reservoir until it is nearly full. Start the engine and let it run for about 10 minutes. At this point, the coolant level will drop slightly as air is purged from the system. Top up the antifreeze until it reaches the "MAXT" mark on the reservoir.
Back when I drove a taxi, I used to think about this a lot. Actually, antifreeze doesn't necessarily need to be changed in winter - what really matters is its actual condition. I usually test it with an antifreeze tester before winter comes. If the reading is about 10 degrees Celsius lower than the local minimum temperature, it's still usable. If it's been used for two or three years or has exceeded 50,000 kilometers, I replace it immediately regardless of whether it's winter or summer - aged antifreeze can easily corrode holes in the radiator pipes (I learned this the hard way last year). Adding water as an emergency measure is a bad idea unless you can get to a repair shop for a complete replacement within three to five days - impurities in water can form ice crystals that puncture the radiator like a sieve. I still remember that snowstorm when my radiator leaked - the towing fee cost me enough to buy three barrels of antifreeze.
Just got scammed by the 4S store last month and finally learned the tricks. The salesperson pointed at the red liquid in the radiator and insisted it must be replaced for winter, but a veteran mechanic quietly told me: the color doesn’t affect antifreeze performance at all! My car originally had green coolant, and switching to red didn’t cause any freezing. Now I’ve wised up—every late autumn, I take a plastic measuring cup, fill it with some old coolant, and leave it in the freezer overnight at -20°C. If it doesn’t freeze, I keep using it. What you really need to watch out for is the rust-colored oil film floating near the radiator cap—that means the corrosion inhibitors have failed, and if you don’t replace it, the entire cooling system could be ruined. Saving $200 on coolant isn’t worth risking an engine repair.
Just helped my neighbor deal with an overheating issue last week. The coolant in his old car hadn't been changed for six years and was clogged like sesame paste. A mechanic friend taught me a trick: first check the fluid level marks in the overflow tank, and top up with dedicated coolant if it's below the minimum line. Never mix different colors or brands - last time an owner mixed red and green and it solidified into a gel-like substance. Friends in the north should pay special attention to the freezing point; when buying bottled coolant, make sure it's labeled for -35 degrees to be safe. If you find the coolant turning black or foaming, it's best to replace the whole system. Saving a hundred bucks now could cost you ten times that in radiator repairs later.
