How Many Kilometers Should Brake Fluid Be Replaced?
3 Answers
Generally speaking, brake fluid should be replaced after a car has been driven for more than 20,000 kilometers. This is necessary to ensure effective braking and safe driving. If used for too long, brake fluid will absorb moisture from the air, reducing braking effectiveness. Replacement can also be done after three years or even longer. As long as the braking performance hasn’t deteriorated, it can continue to be used. However, timely replacement is crucial to ensure effective braking and safe driving. When selecting brake fluid, the following points should be noted: First, the model of the car should match the type of brake fluid used. Second, synthetic brake fluid should be preferred, and high-grade products should be prioritized. Third, professional equipment should be used for replacement. Principle: The volume of brake fluid changes with temperature, so the brake fluid reservoir is equipped with a vent hole. The air drawn in through this hole contains moisture or impurities, which can be absorbed or dissolved by the brake fluid. As a result, brake fluid containing moisture will have a lower boiling point. When a car brakes for an extended period, the temperature of the braking system rises, making the brake lines prone to vapor lock. The air is compressed, which can lead to reduced braking force or even brake failure.
Regarding how often to change brake fluid, I personally think it depends on specific driving habits. Generally, it should be changed every two years or after driving 20,000 to 30,000 kilometers. However, if you frequently drive long distances or often drive in congested urban conditions, you might need to change it earlier, around every 1.5 years or 20,000 kilometers. Having driven several cars, my experience tells me that brake fluid is highly hygroscopic—it absorbs moisture, which lowers its boiling point and can cause bubbling during braking. This makes the pedal feel soft and less responsive, especially noticeable during the rainy season in southern regions. Regular changes not only ensure safety but also extend the life of the brake pump. Don’t forget to check the user manual or consult a technician—don’t skimp on this expense and risk major brake system issues. Make it a habit to check the fluid’s color or smell every six months; if it appears cloudy or has a burnt odor, address it immediately.
Brake fluid replacement frequency is a safety-critical issue. I personally recommend changing it every 2-3 years or 20,000-40,000 km. If you frequently drive in humid environments or on mountainous steep slopes, it's better to shorten the interval. I recall neglecting a replacement once - during highway braking, I nearly had an accident because the moisture-absorbed fluid vaporized under high temperature, significantly increasing stopping distance. Regular maintenance prevents ABS pump or pipeline corrosion. Don't underestimate this detail - spending a little money buys peace of mind. It's best to combine this with your driving habits: frequent braking or high fluid temperature in traffic jams may warrant early moisture testing to ensure stable boiling points. Remember, safety is no trivial matter - always prioritize your vehicle's manual specifications and schedule professional inspections regularly.
