Technician A says that drum brakes can fail to slow the vehicle if driven through deep water. Technician B says that when drum brakes get hot, the brake pedal will drop because the drum expands away from the shoes. Which technician is correct?

Question

Quizplus · Accepted Answer

Both statements made by Technician A and Technician B are correct. Drum brakes can indeed fail to slow the vehicle if they are exposed to deep water, as the water can prevent the brake shoes from making proper contact with the drum. Additionally, when drum brakes get hot, the metal drum can expand, moving away from the brake shoes, which can cause the brake pedal to feel lower or "drop" because the shoes have to move further to make contact with the drum.

Technician a Says That Drum Brakes Can Fail to Slow