When the brake pedal is applied slowly and a squeaking noise is heard at the rear of the vehicle, what could be the cause?

The presence of a squeaking noise at the rear of the vehicle when the brake pedal is applied slowly can indeed often be attributed to the dry backing plate contact surfaces. When the brake system is functioning, the components of the brakes, including the pads and calipers, make contact with these backing plates. If the contact surfaces between the brake pads and the backing plates are not adequately lubricated, friction occurs, resulting in a squeaking or squealing sound every time the brakes are engaged.

The backing plate serves as a mounting point for the brake pads and helps in the overall function of the braking system. Without proper lubrication, there can be unnecessary wear and noise generated as the pads push against the backing plates during braking. This situation often indicates the need for maintenance, such as applying anti-squeal lubricant to these areas.

Other potential issues, such as worn brake pads, defective brake calipers, or damaged rotors, may create sounds or problems, but they typically exhibit different symptoms or may be associated with distinct types of noises. Understanding the nuances of how the brake components interact is crucial in diagnosing brake-related sounds effectively.