Why should you avoid using brakes excessively on long downward slopes?
- To increase tire life
- To prevent brakes from overheating ✓
- To improve engine efficiency
- To save fuel
Answer: B. To prevent brakes from overheating
You should avoid using brakes excessively on long downward slopes to prevent the brakes from overheating.
Why this is the answer
The truck handbook warns that brakes used too much on a long downgrade can overheat and then work poorly, so it tells you to use engine braking as the main way to control speed on long grades. Choosing the right gear before the descent also helps you avoid relying on the brakes. That matches the reason of preventing brake overheating.
Why the other answers are wrong
- A. To increase tire life — Saving tire life is not the reason given; the handbook's warning is about brake condition on a long descent, not tire wear.
- C. To improve engine efficiency — Improving engine efficiency is not the concern here; the handbook discusses controlling speed with engine braking, not making the engine more efficient.
- D. To save fuel — Saving fuel is not the reason in the passage; it warns about brake overheating and how to control speed on a long grade.
Remember it
Remember: on a long descent, pick your gear first and let engine braking carry the load, so the brakes do not have to.
Official handbook: Official MTO Truck Handbook, Use of brakes