Car Brake Facts
A driver on the road is not always concerned with how his brakes work but that his brakes work. So is it important to know that breaks work ...
A driver on the road is not always concerned with how his brakes work but that his brakes work. So is it important to know that breaks work by converting kinetic energy into thermal energy or that friction is used to cool the brakes and slow the car down? A little knowledge can go a long way, especially if you begin to have problems with the brakes.
Drum Brakes
There are two types of drum brakes, single leading edge and double leading edge. Both types have two semicircular brake shoes that sit inside a spinning drum. The drum is attached to the wheel so that when the brake is applied, the shoe pushes out against the inside of the drum causing the heat and friction required to stop the car. The difference between the two is that a single leading edge makes contact with only one part of the drum and a double leading edge makes contact with two parts of the drum.
Disc Brakes
Disc brakes contain two parts. Instead of a drum, there is a metal disc also known as a rotor. A caliper assembly replaces the brake shoes. Hydraulic pistons located within the caliper cause it to push against the back of the break pad. The break pad presses against the disc, which creates the friction necessary to stop the vehicle.
Full Contact Disc Brakes
As technology advanced, a new type of disc brake was created. The idea behind this type of brake is that a standard disc brake only applies pressure to 15 percent of the rotor surface at any given time. With a full contact disc brake, five additional pads are used so that contact is made with 75 percent of the rotor's surface. This system is thought to cool the brake better, and make for a quieter and quicker stop.
Brake Squeals
Oftentimes, a car will come to a stop and as pressure is applied to the brakes, they squeal. There can be a few reasons for that sound. The brake pads or the calipers may be loose or, more often, the squealing sound is caused by a lack of friction material.
Remedies
Copper-based grease can be placed behind the brake pad to reduce squealing but care must be taken when this is done. If the grease gets onto the front of the pad, the brake pad and the rotor will need to be replaced because copper-based grease is resistant to heat and friction. If all the friction material is gone from the brake pad, it is time to get new brake pads installed. It could also be time for an alignment.
