Do My Brakes Need to Be Replaced?

Nearly everything in an automobile functions to help it move, or to make the people in it comfortable while it is moving. The sole component of a car whose purpose is to stop that movement has a big job, and it must do it alone. Its proper functioning is a serious safety issue – and can even be a matter of life and death.

That is why it is critically important to know when to replace the brakes and to do so when the signs and symptoms of failing brakes arise.

How Brakes Work

Conventional brakes are composed of five parts: brake rotors, brake calipers, a master cylinder, brake lines and brake pads. When we talk about replacing the brakes, we are actually talking about replacing the brake pads.

When you step on the brake pedal in your vehicle, you are activating the master cylinder, which uses hydraulics to multiply your force. Without the master cylinder, you would literally have to step on the pedal hard enough to stop the wheels from turning. Good luck with that.

Here is how the brakes work: The force from your foot when you step on the brake pedal compresses liquid in the master cylinder and pushes it through the brake lines to the front and rear brake calipers. Calipers are like big clamps that squeeze the brake pads against the spinning brake rotors from both sides. This creates friction that slows the wheels or stops them from turning altogether. The more pressure you apply to the brake pedal, the harder you push that brake fluid through the lines and the harder the calipers squeeze the brake pads. Although there are several intermediaries between your foot and the turning wheels, it is very much up to the driver whether and how hard to brake.

The importance of working brakes is self-explanatory. Because brake pads work using friction, they eventually wear out. Most brake pads have a natural life of about 50,000 miles, but that depends heavily on how the car is driven and under what circumstances. Vehicles driven in hilly or mountainous areas, under extreme cold or heat, in a lot of stop-and-go traffic, or by drivers with a heavy foot tend to wear out faster.

Most automobile owners’ manuals recommend checking the brakes every 25,000 miles or so. Doing so allows a car care professional to identify problems in advance. But braking issues can crop up between check-ups, so it is always wise to pay attention to signs that the brakes need to be replaced.

Signs Your Brakes Need to Be Replaced

1. Your Dashboard Brake Light Illuminates
Here is the good news and bad news about the brake warning light on your dashboard: The good news is that you don’t have to know anything to see the brake light is on and the car needs to be brought into the shop to check the brakes. It doesn’t require that the driver pay attention to how their vehicle handles, stops, sounds or smells. The bad news is the warning lights usually illuminate late in the process. By the time the dashboard light comes on, the brake pads have already worn extremely thin – under three millimeters, or about a tenth of an inch.

In other words, definitely pay attention to the warning light on the dashboard and bring the vehicle in to be checked right away. Even better, pay attention to the signs and symptoms of brakes in need of repair.

2. The Brakes are Unusually Noisy

Car manufacturers know that if left to our own devices, we drivers will wait to bring our car to the shop until after the brake pads have worn completely out and we are grinding the metal calipers against the metal rotors every time we apply the brakes. This, of course, is extremely dangerous and would result in an enormous repair bill – or hospital bill – because the car didn’t stop.

So, manufacturers have installed an early warning device into the braking system. A metal wear sensor determines when the brake pads are getting thin and makes a metal-on-metal squealing sound to alert the owner to the need for a brake pad change. It is designed to scare the owner into thinking that they are grinding their brakes and rotors. You can always just turn the radio up to drown out the sound, but ultimately that wouldn’t be good for your vehicle, your pocketbook or your safety.

Squealing, squeaking or grinding noises can indicate other problems as well. Rust can form on cars parked for an extended period of time and cause odd noises until a short drive rubs the rust off. If the squeaking continues, the vehicle should be seen by a professional. These noises can come from worn brake hardware, which should be replaced whenever the brake pads are, just to be safe.

3. A Shaky Steering Wheel

A shaky steering wheel can indicate a number of issues, all of which require attention. One of them is faulty brakes, often a brake caliper that is stuck. That means you are driving your car with the brake partially engaged, which is bad for the brakes, and for the safety of the occupants, in multiple ways. Have the brakes, wheels and tires checked if the steering wheel starts shaking.

4. The Car Pulls to One Side When the Brakes are Applied

When the car pulls to one side while braking, it is a sign the pads are wearing at different rates on the left and right wheels. As you can imagine, this is a problem because it means two things – that the car is swerving when you brake and at least one brake pad is shot. This calls for immediate service.

5. The Brakes Pulse When Applied

Pulsing or vibrating brakes indicate warped rotors. When the pads are squeezed against the rotors, they shimmy as the warped rotor turns. This reduces the effectiveness of the brakes and could be a symptom of something worse. Bring in the vehicle for inspection immediately.

6. Pressing the Brake Pedal to the Floor to Stop

This is a classic symptom of worn brake pads. The more worn the brake pads, the more the pedal must be depressed to engage the pads against the rotors. If it is enough for you to notice, it is time for a brake pad replacement.

7. Mushy or Unresponsive Brakes

If it takes a long time for the vehicle to stop after applying the brakes, the problem could be in the hydraulics. For the most part that means leaking brake fluid. Park your car and observe whether there is fluid beneath it. Brake fluid is clear blue, pink or light purple and thinner than motor oil. Also, check the brake fluid reservoir, which is usually mounted on or near the firewall at the rear of the engine compartment, near where the brake pedal is mounted. There is a “full” line clearly visible, and a low fluid level indicates a leak.

Adding brake fluid cures the symptom and may buy you time. If the leak is very slow, this will take care of the issue for the time being. But the level should be checked regularly after refilling the reservoir.

If the brake fluid reservoir is full, the problem is somewhere else, like with the master cylinder. This is cause for concern and should be brought to the repair shop ASAP.

When Do Brakes Need Bleeding?

When fluid leaks out of the brake lines or master cylinder, or any work is done on the braking system other than the replacement of brake pads, air can enter the system. Air is the enemy of a hydraulic system and must be “bled” out by draining the fluid and any air bubbles that might be contained in it.

Bleeding brakes is a simple proposition if you decide to tackle the job as a DIY project. All you need is the right screwdriver – for six-pointed screws known as Torx screws – a container, enough brake fluid to refill the system, and a friend.

Once you find the bleeder screw, open it up with the container underneath and have your friend slowly work the brake pedal down and up to force the fluid and air out of the lines. Once all the fluid is removed, tighten the screw and fill the reservoir until it reaches the full line.

Bleeding brake lines is not a replacement for regular brake maintenance. Keep your brakes in good working order so your brakes can do the same for you.

BlueDevil Products can be found at AutoZone, Advance Auto Parts, O’Reilly Auto Parts, NAPA, Parts Authority, Auto Value, Bumper to Bumper and other major auto parts retailers.