Why Do You Need to Change Your Brake Fluid?
Most Classics run DOT 4 brake fluid. It is hygroscopic, which means that it absorbs water from the atmosphere. It takes about two years in the UK for the water content to get to a point where it is damaging the inside of your brake system.
As the fluid gets older the water content starts corroding the the inside of the master cylinder, servo and the pistons in the callipers. Two things eventually happen:
- Initially the rust will break off and damage the seals as it moves around.
- A little further down the line and one of the components will seize.