How Often Should Brake Fluid Be Replaced?
3 Answers
Brake fluid should be replaced every two years or when the mileage reaches 40,000 kilometers. As the brake pads wear down with driving, the fluid level in the brake fluid reservoir will drop. Brake fluid is a liquid that easily absorbs moisture. If the area where the vehicle is driven has high humidity, it is recommended to shorten the replacement interval. When replacing brake fluid yourself, it is important to first remove the old fluid before adding new fluid up to the maximum level, then securely close the reservoir cap. The brand and type of brake fluid should be selected according to the maintenance manual or replaced directly at a 4S shop. After replacing the brake fluid, it is necessary to completely bleed the air from the brake system lines; otherwise, insufficient braking force may result, leading to longer braking distances.
As a veteran driver with over 20 years of experience, I fully understand the importance of brake fluid replacement. Generally speaking, it should be changed every two years or after driving 30,000 to 40,000 kilometers, because brake fluid gradually absorbs moisture from the air. Over time, the increased moisture lowers the boiling point. During hard braking, if the fluid temperature gets too high, it can boil, resulting in a spongy brake pedal and longer stopping distances, which can easily lead to accidents. I make it a habit to regularly visit professional shops for inspections and fluid changes. By the way, brake fluid is particularly prone to moisture absorption in summer or humid areas, so changing it early can prevent rust and corrosion. Long-term neglect may also corrode brake system components, leading to more expensive repairs. Safety comes first—this is one expense you shouldn't skimp on. Developing this habit will make driving much more worry-free.
I don't think brake fluid needs to be changed too frequently, but you shouldn't delay it for too long either. It's generally recommended to change it every two years or around 30,000 kilometers. I used to neglect this before, and it resulted in poor braking performance. A test revealed excessive moisture content. Checking the owner's manual is the most reliable approach, as requirements vary between different vehicles. Economy models might be a bit more durable in this regard. Changing it too often is a waste of money, but if you don't change it at all, the risk of brake failure increases, leading to higher repair costs. I usually use a simple moisture test pen to check the fluid; if it exceeds the standard, then I replace it. Pay attention to the pedal feel while driving—if it feels too soft or too hard, it's time for a check. Also, integrating other maintenance tasks like tire pressure checks can save money and give peace of mind.
