Disc Brakes vs Drum Brakes: What’s the Difference?

Brakes are an integral component in a functional and safe car, and manufacturers have various options to choose from to best suit the requirements of their designs. Brakes rely on friction to slow the rotation of wheels and disc and drum brakes are two of the most common braking systems because of their ability to produce these properties. Though the way both of these systems generate friction is unique, both have their pros and cons. In this article, the team at VMAX discuss the difference between disc and drum brakes and the advantages and disadvantages of both.

Disc brakes vs drum brakes

Disc brakes and drum brakes are designed with different operating mechanisms, which we’ll explain here along with the various pros and cons:

Drum brakes

Design and operation mechanism

Drum brakes consist of two drum shoes and hydraulic wheel cylinders with pistons inside. When brakes are applied, the pistons push the two drum shoes into the ring of the brake drum, applying pressure that causes friction and the wheel to slow down. It operates when the brake pedal moves brake fluid into the wheel cylinder, causing the pistons to move and push the shoe against the inner of the drum.

Advantages

• Less expensive: Drum brakes are typically less expensive simply because they’re cheaper to manufacture than disc brakes, while also being cheaper to service and maintain.
• Longer life: Drum brakes often last longer because they have a larger area of contact than disc brakes, so the friction is less concentrated and causes less wear.

Disadvantages

• Prone to overheating: As braking systems cause a large amount of heat, drum brakes struggle to dissipate the heat effectively and get sufficient cooling. This can make them prone to brake fade.
• Lower performance in wet conditions: Drum brakes are prone to accumulating water inside and harm the performance of the brakes when this occurs.
• Complex design: Drum brakes are more complex than disc brakes and they have more components involved in their operation, which means more parts can fault and the brakes have more risk of locking.

Disc brakes

Design and operation mechanism

Disc brakes have a flat metal rotor, or disc, which is connected to the hub and spins in tandem to the wheel. They consist of a brake caliper and two brake pads, so when the brake pedal is used the caliper pistons protrude into the brake pads which in turn make the brake pads clamp on to the brake disc. This squeezing applies friction to the disc, slowing or stopping the rotor as well as the wheel.

Advantages

• Dissipates heat well: Disc brakes are less prone to brake fade as they dissipate heat generated from applying the brake better than drum brakes. With less brake fade, they perform more consistently and for longer.
• More cohesive: Due to the nature of disc brakes and the rotors that are squeezed instead of the wheels, it has a more cohesive and linear design which means they’re less likely to lock up and malfunction than drum brakes.

Disadvantages

• More expensive: While disc brakes perform better and more consistently, they are more expensive to manufacture and repair, which is typically reflected in the cost of the vehicle.
• May wear faster: Disc brakes have a smaller contact area of friction, so the brake pads can wear easily and need to be replaced more often than parts in drum brakes.

Whichever brake system your vehicle uses, you can find premium parts and systems at VMAX. Browse our range to find high quality and performing brake parts.