Brake Fade
A temporary reduction or loss of braking power caused by excessive heat buildup in the brake components.
Brake fade is a hazardous condition where a vehicle's stopping power drops significantly under heavy or prolonged braking. It occurs when the friction material on the brake pads and the surface of the brake rotors become overheated. This heat buildup prevents the pads from generating the friction necessary to slow down the spinning rotor.
There are three main types of brake fade: friction fade, where the brake pad compound overheats and loses coefficient of friction; fluid fade, where the extreme heat boils the brake fluid in the caliper, creating compressible air bubbles; and outgassing fade, where resin binder in the brake pads vaporizes and creates a gas film that pushes the pads away from the rotor.
Symptoms of brake fade include a spongy brake pedal, a burning chemical odor, and a dramatic increase in stopping distance. If you experience brake fade, especially when descending a long hill, you should shift to a lower gear to utilize engine braking and pull over safely to allow the brakes to cool down. Upgrading to ventilated rotors, ceramic pads, or high-boiling-point DOT fluid helps prevent fade in heavy-use or towing applications.