In order to slow a vehicle down, the brake pad and rotor must create mutual friction in the braking system. If the brakes are applied and this does not occur, it's referred to as brake fade. When brake fade happens, it results in unexpected or inconsistent braking typically increasing stopping distance and the likelihood of an accident. Brake fading is commonly caused by the overheating of a brake pad and can happen on cars, trucks, SUVs, and motorcycles.
What are the Different Types of Brake Fade?
Overheating the brake pads:
The pads are built to work up to a certain temperature. They tend to increase in effectiveness as they get warm, but above a certain temperature they begin to break down. Components in them can melt and this lubricates the brake disc. Gases can be released as the brake pad material breaks down and that forms a microscopic layer against the pad that reduces friction.
Brake Fluid Fade:
Brake fluid fade is probably the second most likely cause. Auto manufacturers call for brake fluid to be changed periodically. However some vehicle owners ignore these recommendations and don't bother
replacing the fluid for years and years.
This causes the brake fluid to degrade and absorb water and other debris. The water absorption causes the brake fluid to boil at a much lower temperature when it gets hot. When this happens, steam forms in the braking system and steam will compress.
When the fluid gets too hot, the brakes will feel spongy and will no longer will stop the vehicle. Fixing this is simple: Change your brake fluid periodically. Follow your manufacturer recommendations as to how often you should change the brake fluid. Most cars and trucks should have their brake fluids changed every two years or so.
This is not a common cause of brake fade, but it does happen every once in a while.
Sometimes new brake pads have a resin in them and that resin can break down when the pads get really hot. As they break down, they produce gases that will cause the friction between the pads and the rotor to be lost. This in turn causes the brakes to stop working.
How to prevent brake fade: After installing new brake pads, avoid steep hills and prolonged periods of braking for the first week or so. Very few brakes will cause this type of problem but it is good to be aware of it.