It takes hundreds of kilograms of pressure to bring your vehicle to a halt, and the faster you're going, the more you need. Amazingly, you generate all this pressure just by pushing down on your brake pedal. As you press, your master cylinder and power booster amplify the pressure you're applying until it is great enough to stop your vehicle.
The master cylinder uses pistons to force brake fluid from its reservoir into your vehicle's hydraulic system. As a safety feature, the master cylinder is divided into two chambers, each of which controls the brakes on a single axle. This means that even if you have a leak in your hydraulic system, two of your brakes will still work; however, you will have to press the brake pedal much closer to the floor, and there will be a delay before you feel your remaining brakes begin to work.
Master cylinders rarely malfunction, but if a problem is detected, your brake warning light will alert you. Have your brakes serviced immediately if you see this light.
Your brake fluid is designed to be non-compressible and to withstand temperature extremes without freezing or boiling. Over time, however, moisture and other engine fluids can permeate the brake fluid's hoses and mix in with your brake fluid itself. These absorbed fluids compromise your brake fluid's effectiveness because they cannot withstand the same extremes.
For example, the high temperatures created by braking will turn the absorbed fluids and moisture into vapour. This vapour compresses under pressure causing sluggishness in your brake pedal and delayed braking-response times. That's a risk to your safety.
But that's not all: when water and other contaminants mix with your brake fluid, chemical reactions occur that quickly destroy the seals and hoses of your hydraulic system. At best, this results in an expensive repair. At worst, it can lead to sudden brake failure.
Avoid both the expense and danger created by contaminated brake fluid by having it checked regularly.
Your hydraulic system is a network of steel tubes, rubber hoses, valves and seals that carries your brake fluid from the master cylinder to the brakes at each wheel.
This entire system must be strong enough to contain the high pressures generated every time you press the brake pedal. That's why it must be kept free of corrosion and wear.
You can help prolong the life of your hydraulic system - and your own safety - by simply undercoating your vehicle. Undercoating prevents the accumulation of moisture, dirt and rust. It also saves you money by reducing the number of repairs you'll have to your braking system.
If you've ever ridden a bicycle with hand-operated brakes, you can picture how disc brakes work on your car. On a bike, you squeeze a lever that pinches two pads together on the tire. This friction brings you to a stop. In your car, your pressure on the brake pedal forces brake fluid into a caliper, which then squeezes brake pads against a disc rotor. The friction between the pads and the disc rotor stops your vehicle.
However, this friction also wears away the lining of the brake pads. If they wear away entirely, the caliper that holds them will make direct contact with the rotor, severely damage your brake assembly. To avoid this, many brake pads come with a wear sensor that squeals when the pads need to be replaced. If you hear a squeal when you slow or stop your car, have your brakes checked immediately. It will save you an expensive repair.
The disc rotor itself also undergoes wear, developing grooves where the brake pads rub against it. When your brake pads are replaced, the rotor must be filed smooth to provide a good gripping surface for the new pads. This can only be done a few times before the rotor becomes so thin it must be replaced.
Drum brakes work the opposite way from disc brakes. Instead of squeezing in on a disc to slow your vehicle, drum brakes push brake shoes outwards against the inner surface of a drum. The resulting friction brings your vehicle to a stop. When you release the brake pedal, internal springs return the shoes to their original position.
Just like the pads in disc brakes, the shoes in drum brakes also wear away over time and must be replaced to prevent severe damage to your braking assembly.
The drum itself also suffers wear, just like the disc rotor in disc brakes, and must be machined smooth when new shoes are installed. Brake drums are marked with a minimum thickness and must be replaced when they no longer meet this safety measurement.
Your parking/emergency brake is directly connected to the drum brakes on your rear wheels. It bypasses your vehicle's regular braking system, and is designed to give you a way of stopping your vehicle in the event of a complete failure of your hydraulic system.
Since they are not used often, parking/emergency brakes' cables will tighten and corrode over time. This deprives you of an important safety feature and also causes your regular brake pedal to become difficult to push. You can avoid this problem by keeping the cables lubricated and at the proper tension.
Source: Coast Tire & Auto Service
At Gatine-AUTO, we take your safety very seriously. Our technicians are trained and qualified to check your braking system. This verification includes: