Automotive Brakes: A Dummy's Guide

Advantage. Just a word that is pretty harmless alone, yet when a couple of other words are added with it, the situation can be in or out of a persons favor. Taking advantage of...or...taken advantage of...

Most of the times when a person is taken advantage of it is because they are ignorant or naïve to certain aspects of a situation. Hopefully this article can help a person from being taken advantage of at one of our favorite places to go...the automobile mechanic. Most of us would rather have a chipped tooth and need the services of a dentist rather than hear a noise coming from our automobile, because a dentist can show you exactly where the problem is in your mouth with an X-ray. Yet...a noise coming from a car? In most cases people have to take someone elses' word for a proper diagnosis of the problem.

In this article I will focus on one very important part of a persons vehicle, the brakes. When a person hears their brakes squealing one of the first thoughts that usually runs through their head is, "How much is this going to cost me?" A justifiable thought and the squeal you hear can come from a couple of different sources...brake pads that need to be replaced or brake pads that need to be cleaned.

Brake pads are designed with a piece of metal that is called a wear indicator. This is a piece of metal that sticks out of the pad and points somewhere near the rotor. The rotor is the round piece of metal that the brake pads squeeze against to stop the car. Usually the wear indicator will start making a chirping or squealing noise when the brake pads are worn to about 1/8 of an inch. Most pads when they are new are between 3/8 of an inch to ½ of an inch in width depending on the vehicle.

The way to tell if the noise is from worn pads or dirt is simple. Brake pads that are dirty usually only squeal when the brakes are applied...at any speed. Pads that are worn will commonly squeal at low and intermediate speeds in both reverse and forward motions. They will also squeal when coming to a stop.