Most carmakers recommend changing engine coolant every five years or 60,000 miles, whichever comes first. But this varies depending on the type of engine coolant, the severity of your driving conditions and whether you use your vehicle for towing. You might be able to go longer between changes if you stick to the schedule in your owner’s manual and live somewhere with mild weather.
If you frequently drive in stop-and-go traffic or extreme heat or cold, you might need to change your coolant more often. The same goes for if you use your vehicle for off-roading or heavy towing, since those activities put extra strain on the engine.
Over time, engine coolant breaks down and can become corrosive. It can also form deposits that clog the cooling system and reduce its efficiency. So even if you don’t hit the recommended interval, it’s a good idea to have your mechanic check the condition of your coolant during routine maintenance visits. They can test the pH level and specific gravity to see if it needs to be changed.