Hydraulic brakes use brake fluid to cause the vehicle to stop when the brake pedal is pressed down, the master cylinder forces fluid to the cylinders on the four wheels of the vehicle slowing or stopping it altogether depending on the pressure applied.
The main reason why brake fluid is normally replaced is because it is hygroscopic, meaning that it absorbs and retains moisture which in turn causes rust which then leads to leakage in the line and wearing out parts in the system due to friction caused by dirt, silt and metal parts which has rusted and has been dissolved into the brake fluid, the water also causes the boiling point of the brake fluid to lower meaning it boils faster and consequently damages modules and seals.
In addition heat caused by actuation of systems during traction or braking can cause the fluid to breakdown. The importance of driving having efficient braking system cannot be over-emphasized and so transmission fluid change cost should be checked regularly and flushed if need be since the cost of performing a brake fluid flush does not compare to the loss of human life and damage of property due to brake failure in case of an emergency or the cost of repairing and replacing the brake system in the long run which will be much more costly than flushing the brake fluid once every two years as it is commonly done. Also regular brake fluid flush ensures that the vehicle’s lifespan is long.
To check if your car needs a brake fluid flush you have to take out the master cylinder and check if the brake fluid is clear and if it is not then it requires to be flushed, you can flush it yourself if you are careful enough, but it is better to let a professional service and repair company do it for you.
There are various methods used for brake fluid flushing which include gravity, pressure bleed and machine flush where the master cylinder is opened, the fluid drained and it is then cleaned thoroughly to ensure that all contaminants are removed. This is however carried out one brake wheel at a time.
