Brakes are one of the most important parts of your car. Without a gas pedal you wouldn’t get anywhere, and without a brake pedal, you wouldn’t get there in one piece. So, what are they?
Whether you’re braking on a bicycle, motorcycle, or car, you’re always using friction. On cars this is accomplished either through disc brakes or drum brakes. Disc brakes work by having brake pads ‘pinch’ a brake disc (often referred to as a rotor) attached to the wheel.
Drum brakes involve a ‘drum’ attached to, or as a part of a vehicle's wheel assembly that houses the mechanical parts of the brake. Two shoes, similar in effect to brake pads, inside the drum push against the wall of the drum to slow the vehicle.
Disc brakes are what you’ll find on most cars today, though some vehicles are made with disc brakes on the front wheels and drum brakes on the rear wheels. Disc brakes are much easier to maintain and replace than drum brakes, and can dissipate heat built up from braking much more effectively.
While drum brakes aren’t as common in most passenger vehicles, they are quite common on heavier vehicles such as large trucks and buses, because they offer greater braking force than a similar sized disc brake.
Brake pads come in a variety of different materials, they range from: Non-metallic or organic, Semi-metallic, metallic, and ceramic.
Semi-metallic, non-metallic, and ceramic pads are what you’ll find on your car, with metallic pads being reserved for race cars. Each type of material offers some advantages and disadvantages that you should take into consideration when replacing your pads.
Semi-metallic brake pads last longer than ceramic or non-metallic pads, but cause greater wear to brake discs.
Non-metallic, or organic, brakes are much easier on your rotors but the pads themselves need to be replaced much more frequently than semi-metallic or ceramic pads.
Ceramic brake pads fall somewhere in between non-metallic and semi-metallic brake pads in terms of durability, but fail to dissipate heat generated by braking, which can negatively impact other components in the brake system. Ceramic pads are also much quieter than other pads, but can also run a bit on the expensive side. The type of pad that’s best for your vehicle depends on your driving habits. Non-metallic pads are ideally suited for city driving, where brakes are frequently, but lightly used.
Semi-metallic pads are best left to sports cars, while ceramic pads offer a good compromise between the high performance and durability of semi-metallic pads, and the rotor friendly ease of use of non-metallic pads, with the downside of increased cost.
As you drive and brake, your brake pads and the brake disc will wear down over time. Most disc brakes can be checked with minimal labor and many come with some form of wear or life indicator, whether that be an electronic indicator, or a mechanical one. Make sure you know if you have an indicator and what the signs are that your brakes need replacing by talking with your mechanic.
Rotors generally last longer than pads, but should be replaced with your pads as leaving on old rotors can lead to uneven wear and prevent brake pads from gripping the rotor adequately. This can cause problems ranging from noise and shaking, to decreased braking power.
While it may be tempting to tough it out through squishy or squealing brakes, driving on worn out brakes isn’t just a liability for you, but everyone around you as well. Great car maintenance starts with addressing problems when they come up, and not down the road.