What are the main components of brake fluid?

[StAlexa]

There are three types of brake fluid: 1. Castor oil-alcohol type, which is made by blending 45% to 55% refined castor oil with 55% to 45% low-carbon alcohol (ethanol or butanol). 2. Synthetic type, which is made by blending ethers, alcohols, esters, etc. with additives such as lubricants, antioxidants, rust inhibitors, and rubber swelling inhibitors. 3. Mineral oil type, which is made by blending refined light diesel oil fractions with thickeners and other additives. The method for replacing brake fluid: 1. Turn off the vehicle and open the engine compartment cover. Use a syringe to extract the fluid from the reservoir until it reaches the bottom. 2. Fill the reservoir with new brake fluid. 3. Use a jack to lift the vehicle, starting with the rear wheels, and remove the tires. 4. Locate the brake caliper's bleed screw and remove the rubber dust cap. 5. Use a wrench to loosen the bleed screw, attach a rubber tube to it, and connect the other end to a drain bottle. 6. Go inside the vehicle and start pumping the brakes. If the fluid coming out of the rubber tube is the lighter new fluid, the fluid change for that wheel is complete. Stop pumping the brakes, reinstall the tire, and repeat the process for the remaining three wheels. 7. After all four wheels have been bled, check the fluid level in the engine compartment reservoir. If it has reached the lower limit, add new brake fluid as needed.