Michigan State Brakes Certification Practice Exam

If a car has excessive pedal travel when braking, what might be the issue?

1. Worn brake linings

2. Faulty brake booster

3. Excessive clearance between the shoes and drum

4. A malfunctioning ABS system

The correct answer is: Excessive clearance between the shoes and drum

Excessive pedal travel during braking can indeed be a result of excessive clearance between the shoes and the drum. This situation often arises when the brake shoes are not adjusted properly, leading to a gap that prevents the shoes from making effective contact with the drum until the brake pedal is pushed significantly farther down. As the driver presses the brake pedal, they must travel further to overcome this gap before the brakes can engage, resulting in a sensation of excessive pedal travel. Additionally, while worn brake linings, faulty brake boosters, and malfunctioning ABS systems can lead to braking issues, these problems typically manifest in different ways. Worn linings might cause the brakes to feel less effective or lead to noises, but they don't necessarily create extra pedal travel unless the linings are extremely worn. A faulty brake booster can impact the effort required to press the pedal but doesn't primarily affect the travel distance. A malfunctioning ABS system would generally provoke other issues like pulsing in the pedal during braking rather than excess travel. Thus, excessive clearance between the shoes and drum provides a direct correlation to the increased distance the pedal must travel before the brakes engage effectively.