At What Moisture Content Should Brake Fluid Be Replaced?

1 Answers
StJudah
07/25/25 4:46am
Brake fluid should be replaced when its moisture content exceeds 2.5%. The characteristics of brake fluid are: 1. It has a very low freezing point, maintaining good fluidity in low-temperature conditions; 2. It has an extremely high boiling point, preventing vapor lock in high-temperature conditions; 3. It undergoes minimal quality changes during use, avoiding corrosion of metals and rubber. The working principle of brake fluid is that it is an indispensable part of the braking system, serving as an incompressible medium for force transmission within the system. The pressure output from the master cylinder is directly transmitted to the wheel cylinders through the brake fluid. In a sealed container or a fluid-filled pipeline, when the fluid is subjected to pressure, the pressure is quickly and uniformly transmitted throughout the fluid.
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