What Are Drum Brakes?
by Mashum Mollah Automotive 25 September 2019
If you own a car, you probably frequently make trips to an auto parts store near you to keep your vehicle in good working condition and replace parts. Depending on how experienced you are with mechanics, you may know how to replace a radiator or switch out your wiper blades. But do you know much about drum brakes and why they matter? Here’s what you should know about how drum brakes work and how to tell if they need to be replaced or serviced.
What Do Drum Brakes Do?
Drum brakes slow or stops a car by using friction to press brake pads or shoes against a brake drum. They work on the same basic principle that disc brakes work on: to press shoes against a surface that spins. Many cars have disc brakes on the front end and drum brakes on the rear. The two types of brakes do the same thing but in different ways. Drum brakes are difficult to service and have more parts than disc brakes.
Benefits of Drum Brakes
Drum brakes are generally more affordable than disc brakes to manufacture. They are also easy to incorporate into an emergency brake system. Here are a few more advantages they offer over disc brakes:
- Require less input force
- Better corrosion resistance
- More braking force
- Increased friction contact area
- Lower heat generated in rear drum brakes
- Easy to recondition
Of course, there are a few drawbacks to drum brakes as well, including the opportunity for brake shoes to overheat, thermal expansion under hard braking (which requires the driver to push harder on the brake pedal) and time-consuming maintenance requirements.
Drum Brake Hardware
If you need drum brake hardware, it’s important to purchase it at an auto parts store instead of reusing old hardware. If you’re concerned about saving money, you may be eligible for AutoZone rewards that can save you money on future purchases. Attempting to save money by reusing old drum brake hardware is unwise. It’s also important to replace any worn, stretched or damaged drum return springs because they can cause the brakes to drag.
Signs You Need New Drum Brake Shoes
It’s easy to tell when you need drum brake shoes, once you understand the common signs of worn shoes. If your hand brake feels lose and requires you to yank hard on it to keep the car from rolling away, you may need new brake shoes. Vibrations under the brake pedal when slowing down or stopping are also common with worn shoes.
Finally, if you hear any strange scraping or squealing noises when braking, it’s imperative to have your brakes checked immediately. Once the brake shoes have worn down to the point where only the shoe’s metal platform remains, you will probably need to replace the entire drum brake. This can be costly but is worth the expense to keep yourself and your passengers safe on the road.
If you aren’t a skilled mechanic, it’s best to leave repair and replacement of your drum brakes to the professionals. You can purchase the parts you need from an auto parts store to get the best price, but leave the complicated mechanics to those who know what they are doing.