How Many Kilometers Should Brake Fluid Be Replaced After?
2 Answers
Generally, the maintenance cycle of brake fluid is time-based, with a replacement cycle of two years. Some manufacturers specify two years or 40,000 kilometers, whichever comes first. Below is more information about automotive brake fluid: 1. Essentially, whether brake fluid needs replacement mainly depends on the water content in the brake fluid. 2. Since brake fluid is highly hygroscopic, over time, a large number of bubbles will form in the brake lines, which can significantly affect the performance of the braking system. 3. When the braking system operates, it generates high temperatures, causing the water in the brake fluid to vaporize. The gas is easily compressed, leading to soft brakes and dangerous loss of braking power. 4. It is recommended to use a brake fluid tester to measure the moisture content in the brake fluid.
After driving for so many years, I think brake fluid generally needs to be changed every 30,000 kilometers, and this number is quite reliable. I used to have an old car that went over 35,000 kilometers without a change, and the brake pedal became soft, especially during rainy days on the highway—it almost caused an accident. Later, the mechanic explained that brake fluid absorbs moisture, lowering its boiling point, and prolonged downhill driving could lead to vapor lock failure. Most manuals recommend changing it every two years or between 30,000 to 60,000 kilometers, depending on driving habits—if you often drive on mountain roads or in humid areas, it’s better to change it earlier. Personally, I’ve made it a habit to handle it during routine maintenance. It costs a few hundred bucks, but it buys peace of mind. After all, safety comes first—don’t wait for danger to knock on your door.
