Final answer:
A drum out of round by more than 0.010 inches typically causes vibration, uneven wear, possible damage to the brake system, and decreased braking efficiency, which are noticeable through pulsation and noise during brake application.
Step-by-step explanation:
A drum out of round by more than 0.010 inches can cause vibration when the drum rotates, potentially leading to following issues:
- Uneven wear on the drum and associated components
- Possible damage to the brake system over time
- A decrease in the efficiency of the braking system
Having a roundness tolerance exceeding the limit of 0.010 inches means the shape of the drum deviates from a perfect circle. As a consequence, the surface does not contact the brake pads evenly during operation. This can lead to pulsation in the brake pedal, which drivers may notice as a rhythmic throbbing or shaking when braking. The pulsation can also induce noise and harshness during brake application, which can be both uncomfortable and indicative of an increased risk of premature wear or failure. As safety is critical when it comes to vehicle brakes, any signs of such symptoms should be inspected and addressed promptly by a professional mechanic.