What is a common sign of worn brake shoes in an air brake system?

In an air brake system, worn brake shoes typically lead to increased stopping distances and may also produce noise during braking. Brake shoes lose their effectiveness as they wear down, resulting in a longer distance required to bring the vehicle to a stop. This is critical for safety, especially when driving larger vehicles that rely on effective braking to manage their speed and control.

Additionally, when brake shoes wear unevenly or become excessively worn, they can create noise during operation, such as grinding or squealing sounds, which indicate that the friction material is deteriorating. Maintaining awareness of these signs is crucial for preventing brake failure and ensuring the vehicle can stop safely in a timely manner. Other options, such as decreased fuel efficiency or vibrations, do not specifically correlate with the condition of brake shoes. They may point to different mechanical issues within the vehicle.