General Knowledge · Mountain Driving
What braking technique helps prevent brake fade while descending a long grade?
1.Brake firmly to drop a set amount of speed, then fully release, repeating as needed so the brakes can cool between applicationsCorrect answer
2.Apply light, continuous pressure to the brake pedal for the entire length of the descent, so that speed never builds up at all down it
3.Pump the brake pedal rapidly and lightly for the entire length of the descent, to keep the linings from heating up
4.Wait until near the bottom of the grade, then brake hard for the whole of the rest of the way down to level ground
Explanation
The correct technique is to brake firmly enough to knock a set amount of speed off, then release the brakes completely so they can cool, and repeat this cycle as needed, rather than keeping the brakes engaged continuously. 49 CFR 383.111(a)(19)(iii) names proper braking technique as required knowledge without describing this pattern, so it is standard driver-training content, attributed to the manual. The wrong options each keep the brakes engaged in some continuous or repetitive form, light steady pressure, rapid light pumping, or a late hard application, all of which deny the brakes the cooling-off time that prevents heat buildup and fade.
Source: 49 CFR 383.111(a)(19)(iii)
Related Mountain Driving questions
- Under federal regulation, which three practices must a commercial driver have knowledge of for driving upgrade and downgrade on mountain roads?
- What is the correct way to choose a safe speed before starting down a long, steep downgrade?
- When should a driver select the gear for descending a steep grade, and which gear is generally correct?
- Why can continuous, heavy use of the service brakes on a long downgrade cause the brakes to lose stopping power?