In the braking system of a heavy vehicle, what is the "fading" effect?

Question

DentroTest · Accepted Answer

The "fading" effect (thermal fatigue of the brakes) is the drastic reduction, or momentary loss, of braking effectiveness caused by excessive heating of the friction elements (pads, shoes, discs or drums). In heavy vehicles it usually occurs when the service brake is used continuously on long downhill slopes. When it overheats, the friction material loses grip and brakes less. To avoid it, it is advisable to reduce use of the brake pedal, select lower gears and make use of engine braking and retarders so that the system cools down. The assistance mechanism that reduces the force on the pedal is the brake booster, and the system that prevents the wheels from skidding in hard braking is the anti-lock system (ABS): neither of them is fading.

In the braking system of a heavy vehicle, what is the "fading" effect?

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