On downhill roads, braking loss is most likely in which vehicle category?

• A. Buses
• B. Trucks
• C. SUVs
• D. Motorcycles

Answer: (B)

Braking loss, or brake fade, happens when brakes overheat from extended use on a downhill. The key idea is that a vehicle’s braking system must absorb the energy that slows it down, and that energy grows with mass. Heavier vehicles require more braking energy to shed the same speed, so their brakes heat up faster on a long descent. When brakes overheat, their friction decreases and stopping effectiveness drops, making braking loss more likely.

Trucks have the greatest mass and often carry heavy loads, so they store more energy and put bigger demands on the braking system during a descent. That combination makes them the most susceptible to brake fade on downhill roads, more so than buses, SUVs, or motorcycles. To manage this, use engine braking by downshifting and maintain a safe speed to lessen brake heat.