Can Different Types of Brake Fluid Be Mixed?

[StGemma]

Brake fluid should not be mixed. Different types and brands of brake fluid contain varying compositions, and mixing them can lead to a decline in performance and chemical reactions, which may reduce the braking effectiveness of the vehicle and negatively impact the fluid's temperature resistance, compromising driving safety. Brake fluid is a functional liquid used to stop wheel rotation, serving to transmit energy while also providing anti-corrosion, anti-rust, and lubrication benefits. Types of brake fluid: Castor oil-alcohol type, made from refined castor oil and low-carbon alcohol; Synthetic type, formulated with ethers, alcohols, esters, and additives for lubrication, oxidation resistance, rust prevention, and rubber swelling resistance; Mineral oil type, produced from refined light diesel fractions with thickeners added. Precautions for using automotive brake fluid: If gasoline, diesel, or engine oil accidentally mixes into a synthetic brake fluid-based braking system, the incompatibility between fluids can reduce braking effectiveness. For vehicles driven normally for 40,000 kilometers or with brake fluid used continuously for over two years, the fluid may degrade due to prolonged use, so timely replacement is essential. Vehicles equipped with a brake fluid level warning device should monitor whether the warning light is flashing and if the sensor is functioning properly. When the brake fluid is low, it should be replenished promptly. Stored brake fluid should be maintained between the marked minimum and maximum capacity levels. If the brakes exhibit inconsistent performance during normal driving, the brake fluid should be replaced immediately. Before replacement, clean the braking system thoroughly with alcohol. If the vehicle pulls to one side during braking, conduct a comprehensive inspection of the braking system. If the wheel cylinder rubber cups are excessively swollen, it may indicate poor-quality brake fluid. In such cases, replace the fluid with a higher-quality option and also replace the rubber cups. During seasonal changes, especially in winter, if braking performance declines, the brake fluid grade may not be suitable for winter conditions. When replacing, choose a brake fluid with lower viscosity at low temperatures. Do not mix different types or brands of brake fluid. For braking systems with specific requirements, use the designated brake fluid brand. Since formulations vary across brands and types, mixing can degrade performance. Even brands labeled as compatible or interchangeable may not perform satisfactorily, so avoid long-term mixed use. If water or impurities are found in the brake fluid, replace or filter it immediately to prevent insufficient braking pressure and compromised braking performance. Regularly replace brake fluid: The volume of brake fluid changes with temperature, so the reservoir has a vent hole. Air drawn in through this hole may contain moisture or contaminants, which can lower the boiling point of the fluid. During prolonged braking, the system heats up, increasing the risk of vapor lock due to compressed air, leading to reduced braking force or failure. For safety, brake fluid must be replaced periodically.