If your vehicle has drum brakes and you hear a squeal, it's a good warning sign that your brakes need lubrication. Once the contact points no longer have lubrication, the metal starts to rust. That causes the shoes to scrape on the backing plate and thus squeal.

What do bad drum brakes sound like?

Scraping noises when brakes are pressed

If the brake drums become excessively worn, they may give off a scraping or scratching sound when the brakes are depressed. This usually means the brake shoes have also become severely worn, and a close inspection would be required to determine the exact cause of the noise.

Is it normal for drum brakes to squeak?

When it comes to drum brakes, the most common cause of screeching and squealing is worn out shoes. Other causes can be from improper adjustment or contact with the axel backing plate.