Which is least likely to cause brake drums to overheat?
- Summertime ✓
- Hard braking
- Pulling heavy loads
- Long downhill grades
Answer: A. Summertime
Summertime is the least likely of these to cause brake drums to overheat.
Why this is the answer
The handbook ties brake-drum overheating to brake work and load: stopping very heavy vehicles puts pressure on the brakes, long downgrades heat the drums, and hard braking is part of the same danger. It does not list summer weather itself as a cause. So among these choices, summertime is the least directly connected to overheating.
Why the other answers are wrong
- B. Hard braking — Hard braking presses the linings against the drums and is one of the braking actions the handbook connects with heat and reduced braking power.
- C. Pulling heavy loads — A heavy load increases the stopping pressure on the brakes, and the handbook says stopping extremely heavy vehicles can cause brake drums to overheat.
- D. Long downhill grades — On long downgrades, hot drums expand and can reduce or even eliminate braking, so this is a recognized overheating condition.
Remember it
Ask what makes the brakes work hard: heat comes from braking and load, not from the calendar.