Wear, corrosion, distortion and other causes of failure. You can expect to have to replace front discs and pads during a vehicle’s life due to wear but are more likely to have to replace rear pads and discs because of corrosion.
Braking systems rely on friction to bring the vehicle to a halt – fluid pressure pushes brake pads against a cast iron disc or brake shoes against the inside of a cast iron drum. Parking brake – When disc brakes were first fitted to all four wheels – initially to large cars and small sports models a small drum brake was incorporated into the centre of the rear hubs for the parking brake. As ‘discs all round’ has become commonplace, parking brake design has moved on and many now work by applying pads directly to the main discs – eliminating the need for a separate drum parking brake.
Brake Fluid Hydraulic brakes rely on the principle that you can’t compress a liquid. Under heavy braking, such as a long downhill descent, the brakes get hot and heat up the brake fluid. In extreme cases, water in the brake fluid can boil and vaporise.For safety brake fluid should be replaced every two years, regardless of mileage.