How to Determine When to Replace Brake Fluid?
3 Answers
If the water content in the brake fluid reaches 3%, it needs to be replaced immediately. Below is relevant information about brake fluid: 1. Definition: Brake fluid is a liquid medium that transmits braking pressure in a hydraulic braking system, used in vehicles equipped with hydraulic braking systems. Also known as braking oil or force oil, brake fluid is an indispensable part of the braking system. Within the system, it acts as a force-transmitting medium. Because liquids cannot be compressed, the pressure output from the master cylinder is directly transmitted to the wheel cylinders through the brake fluid. 2. Precautions: For vehicles equipped with a brake fluid level warning device, always monitor whether the warning indicator light is flashing and whether the warning sensor is functioning properly. When the brake fluid is insufficient, it should be replenished promptly. The stored brake fluid should be maintained between the marked minimum and maximum capacity levels.
As a long-time experienced driver, I believe the most important method to determine whether brake fluid needs replacement is by observing the usage time. Generally speaking, it should be changed every two years or 40,000 kilometers, which is almost an industry consensus. However, actual usage should also consider road conditions. For example, when I frequently drive on mountain roads with constant braking, the fluid deteriorates faster. Also, remember to open the hood and check the brake fluid reservoir's level mark. If the fluid level drops below the 'min' line or the color turns dark brown like soy sauce, it's time for a change. The most concerning situation is when the brakes suddenly feel soft, with the pedal losing its elasticity – that absolutely cannot be delayed. It's best to completely flush the entire system during each fluid change, as air bubbles can severely affect braking performance.
During routine maintenance, the technician told me that besides checking the mileage, professionally testing the moisture content in the brake fluid is crucial. Nowadays, most repair shops have those test pens with indicator lights that can be inserted into the fluid reservoir to display the moisture level. If the moisture content exceeds 3%, it's time to change the fluid, as water can corrode metal components and lower the boiling point. From my own experience, regularly checking the fluid condition is essential, especially during periods of frequent rainy weather when brake fluid absorbs moisture more quickly. I recommend not skimping on this expense, as changing the fluid is much cheaper than replacing brake discs and significantly improves safety performance.
