Hearing unusual noises when driving your car? Noticing a squeak, a rumble or a grinding sound that you haven’t heard before? If you are, no doubt you find them quite disconcerting. While these noises might not mean something is about to fall off your vehicle, they can be an indication that there is trouble ahead and they shouldn’t be completely ignored.
A noise that most car owners will experience at some point in their driving life is a squealing sound when the brakes are engaged. It’s an irritating sound and can be pretty embarrassing if every time you touch the brake pedal your car squeals like an excited piglet. However, a persistent squeal from the brakes is an indication that something serious is amiss and needs to be investigated.
HOW DO BRAKES WORK?
Brakes are one of the simplest parts of a car to understand. Pressing the brake pedal increases the pressure of the fluid in the brake lines. This pressure builds through the lines to the brake calipers which are then forced into a movement that presses the friction material of the brake pads against the brake rotors (disc). Simple.
SO WHY THAT SQUEAK?
The squeak will most likely be a result of worn brake pads and is actually a warning ‘alert’ built into the pad.
Brake pads are fitted with a wear indicator – a piece of metal that juts up along the side of the friction material that is pushed against the brake rotor. Once the friction material has worn down far enough, this metal indicator will start to make contact with the rotor resulting in the squealing noise. Every time the brake system is used from this point on, the squeal will occur – a sure sign that, at the very least, the brake pads need replacing.
This persistent squeal should not be ignored. If you do ignore it, the pads, and the warning indicator, will eventually wear away completely and the metal backing plate of the pad will begin to grind against the rotor. At this point, not only will new pads be required but possibly new rotors as well, and repairs can begin to get pricey. Beyond that, of course, is the fact that the brakes would be all but useless and driving would be extremely dangerous.
It’s worth remembering that even brakes in good condition will squeak and squeal from time to time, especially if put under a lot of stress such when they are used heavily in an environment such as mountain roads. This may mean the noise will be a temporary issue. It is when the squeal is persistent that you should look to take your car to a qualified mechanic to get the brake pads, and braking system, examined and serviced.
KEEP IN MIND
- Car brakes will often squeal when they are hot or under pressure. Mountain driving can often lead to squealing brakes.
- High-performance carbon-metallic brake pads are prone to squealing.
- All brakes will squeal from time to time. The time for concern is when it becomes a consistent squealing.
WANT TO LEARN MORE?
MTA Queensland’s Vehicle Maintenance course is designed for those who are interested in gaining valuable information and learning good practices for everyday vehicle use. The result: a safer journey with fewer breakdowns and repairs. If you have ever wanted to learn how to carry out preventative maintenance, then this course is for you.
21 November 2019
Please note the information contained on this page is general in nature and does not take into account your specific needs or circumstances. You should consider whether the information is appropriate to your needs, and where appropriate, seek professional advice.