What Is A Brake Drum?

Stopping your car is just as important and getting it moving in a particular direction. Brake drum systems are one technique. Okay, what is a brake drum?

The brake drum mechanism is one that is very effective when it comes to slowing a car down. It has, however, an inherent weakness. It builds up massive amounts of heat fairly quickly and has problems dissipating it. This is because the brake system is fitted into an enclosed space that looks a bit like one of those things the push in curling matches. In contrast, disc brake systems are open to the air and cool down much quicker.

The brake drum works by using friction to slow the vehicle. The back of the drum is a plate like structure that looks a bit like a Frisbee, but with a much wider rim. Inside of this structure sits the mechanics of the brake. Generally, these mechanics involve a piston being moved by hydraulics or a wire. When the driver presses on the pedal, the piston activates and pushes shoes outwards against the rotating drum and this causes the car to stop.

The brake shoes in the drum serve the same purpose as brake pads on a disc system. They are coated with abrasive material that will create as much friction as possible without raising temperatures excessively. The material usually includes asbestos in one form or another since it is impervious to heat.

The modern car tends to come with disk brakes on all four wheels. That being said, some cars still use drum brakes on the rear. Trucks and vans incorporate drum brake systems much more often.

What is a brake drum? It was once the predominant brake system used on vehicles, but is now diminished as disc brake systems continue to improve and be used more.

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