When talking about the maintenance of brake system, most car owners will focus on the brake pads, as for the brake fluid which is equally important, is ignored. The function of brake fluid is transmission, which is to transport the brake power to the brake system. When we step on the brake pad, the vacuum booster will push the main brake pump; the brake pump will then push the brake fluid and transport the force to the brake sub-pumps belong to 4 wheels; the brake sub-pumps will push the brake pads, the brake pads will squeeze the brake plate and form the brake force.

The brake fluid needs to be replaced in every 40000 km or 2 years. Hygroscopicity of brake fluid is strong, especially for frequent car wash or humid environment. When the water reaches to 3 % in brake fluid, it will affect the driving safety. The brake performance will get lower down and produce strong air pressure, even squeeze up the brake lines and result in brake fluid leakage and brake failure.

Besides, due to the brake fluid is flowing in the brake line for a long time, the metal powder of main brake pump and sub-pump will seep into the brake fluid. This will make the wear of belt and piston more serious and affect the brake performance, which will make the brake weak or inaccurate.

Water and impurities are solubilized in the brake fluid; it’s hard to separate from it. Therefore, we can only replace it, nothing else we can do. The specialist will recommend replacing the brake fluid once in a constantly use over 40.000 km or 2 years.