Home › CDL Practice Tests › Air Brakes Questions › Question 180
Why does riding the brakes with light continuous pressure wear them out and cause fade on a mountain grade?
- A.Light pressure uses more air than firm pressure
- B.It keeps generating heat without a cooling interval, so lining and drum temperatures keep climbing
- C.The brakes only heat up when the pedal is fully released
- D.Continuous pressure keeps the drums cold and wet
Correct answer
B. It keeps generating heat without a cooling interval, so lining and drum temperatures keep climbing
Why
Even modest braking converts a large amount of the truck's motion into heat when it continues for miles. Without release time to shed that heat, friction falls, wear accelerates, and the pedal can begin to feel normal while stopping power disappears.
Manual topic: Air Brakes - Brake Fade and Heat · From the Air Brakes practice bank (AB-180).