How Often Should the Vehicle's Coolant Be Replaced?
2 Answers
The vehicle's coolant should be replaced every two years. This is just a reference interval. For commercial vehicles with higher mileage, the replacement interval should be shorter. Since driving conditions vary for each vehicle, the replacement should be based on actual usage. Regularly check the coolant level and top it up if it is insufficient. If suspended particles, sediment, or signs of deterioration or discoloration are observed in the coolant, replace it immediately and flush the system. Coolant Replacement Procedure: Before performing a complete coolant replacement, conduct a thorough inspection to check for leaks or cracks in all hoses, with a focus on the five-way hose. The five-way hose, named for its five connection points to various components, distributes coolant to different parts of the vehicle. If any leakage is detected in this area, replace the hose or reseal the connections as needed. Drain the old coolant, then flush the system with clean water. Add water to the coolant reservoir and continue filling until clean water flows continuously through the engine cooling system. Start the engine and let it idle for 3 to 5 minutes to circulate the water. Initially, the discharged water may appear slightly pinkish. Keep adding clean water until the discharged water runs clear. Remember to disconnect the heater hose to drain the heater core completely. About one hour after draining, add the new coolant through the radiator hose to allow rapid filling. Then, pour another container of coolant into the reservoir until it is nearly full. Run the engine for about 10 minutes, during which the coolant level may drop as air is purged from the system. Top up the coolant to the "MAX" mark on the reservoir.
My experience with frequent coolant changes is roughly every three to five years, depending on your car type. When I drove an older Toyota, the manual recommended changing it every two years or 30,000 kilometers. Now, with newer models using so-called long-life coolant like G-05, it can last about five years. However, I always check the coolant reservoir during every oil change to ensure it remains clear, without cloudiness or sediment. I remember last winter when I delayed the coolant change, my car almost failed to start during a cold snap. The mechanic said aged coolant can corrode the engine’s internal pipes, and repairs could cost at least a couple thousand yuan. I usually recommend changing it in spring or autumn to avoid extreme weather issues. A simple method is to buy a cheap test strip for a few bucks to check the pH level—that’ll tell you if it’s time for a change. The key is regular maintenance; don’t wait for problems to arise. Spending a little to protect your car is what matters most.
