All About Brakes: How to Tell When Your Brakes Are Bad

June 11th, 2021 by

A close up shows a Nissan brake service being done by a gloved mechanic.

You’re probably well aware of when the oil needs to be changed in your vehicle or what to do when your tire pressure is low, but do you know how to tell when your brakes are bad? Modern vehicles are usually equipped with in-vehicle alerts that tell you when it’s time to change your oil or put air in your tire, but there isn’t always an alert for when your brakes need servicing. This is why we’re here to lend a hand by offering our Nissan brake service.

So, how do you know when your vehicle’s brakes are bad? Before you find yourself stuck without any stopping power, we’re here to help you learn more about how your brakes work, the maintenance you can do to ensure their longevity, and ways to tell when they’re bad and need servicing. Let’s get started!

How Brakes Work

Your foot engages the brake pedal, and your vehicle stops. It’s as easy as that, right? There’s a little more to your vehicle’s brakes than that, and here’s why. Each wheel on your vehicle is equipped with a brake that’s operated by a hydraulic system. Many vehicles have four-wheel disc brakes because disc brakes provide more effective stopping power. However, because disc brakes are more expensive, some affordable vehicles only have disc brakes in the front and drum brakes in the rear.

Both disc and drum brakes respond the same way. When you engage the brake pedal, mechanical leverage amplifies the force of your foot to cause a reaction. This reaction signals the piston to move into the cylinder to squeeze hydraulic fluid out of the end. This fluid is forced into the braking system through a complex network of brake lines and hoses. When your brakes are working properly, pressure is evenly distributed to all four brakes. This pressure then creates friction between the brake pads and the rotors to bring the vehicle to a stop.

A mechanic is changing a brake pad during a Nissan brake service.

How to Tell When Your Brakes Are Bad

#1 Unusual Noises

The only sound that you should hear when you’re driving down the road is the purr of the engine. If you hear squeaking, grinding, or squealing from your vehicle, then it’s time to check your brakes. The noises you hear from the brakes can mean different things. For example, if you hear a high-pitched noise that stops when you apply the brakes, then you’ll need to check the brake pad wear indicators. The indicators are made of steel and will screech when they come in contact with the rotor, signaling that it’s time to replace the brake pads before you damage the rotors.

While the high-pitched noise is a good indicator of brake pad wear, the grinding noise associated with the brakes is a little harder to figure out. If you hear a grinding sound when you apply the brakes, this could be nothing more than gravel or rocks that are caught in the brake caliper. This is an easy fix.

On the other hand, grinding can also mean more extensive brake issues. The noise could signify that you’ve ignored servicing your brakes for too long and, as a result, the pads are worn down to nothing, and the steel backing plates are in contact with the rotor. Another potential issue is that the brakes aren’t properly lubricated, and the grinding is coming from the brake shoe scraping against other metal contact points.

#2 Unusual Odor

Noises are easy to hear when you’re driving down the road, but did you know that you can also tell if your brakes are bad if you smell something burning while you’re driving? This unusual odor is often described as a pungent, chemical odor and typically occurs on steep roads where you’re repeatedly braking hard. This is a sign that your brakes are overheating, which means it’s time to pull off the road and allow the brake fluid to cool. If the fluid gets hot enough to boil, your brakes can fail and create an extremely hazardous driving condition.

#3 Unusual Movement

Aside from unusual noises and odors, it’s also common to feel unusual movement when your brakes are bad. This movement is typically described as wobbling or shaking that occurs when you apply the brakes. For example, you engage the brake pedal, and your steering wheel shakes or vibrates. This is a sign that your brake rotor, which is the disc that the brake pad hugs to slow the vehicle, is warped or pitted. Rotors must be smooth and even to your vehicle’s specifications. When your brakes are serviced, the technician will resurface or replace the rotors to eliminate any flaws and minimize the potential for brake failure.

Beyond an uneven rotor, unusual movement can signify other issues as well. For example, the shaking could be caused by the improper release of the brake caliper, which squeezes the brake pads against the rotor to slow the vehicle. It could also signify that the lug nuts on your wheels were not properly installed, which is common when your tires are removed, and the lug nuts were not tightened properly. If you find that the movement doesn’t have to do with shaking or wobbling but with your vehicle pulling to one side, then this may signify that you have a bad brake caliper or a brake hose.

#4 Leaking Fluid

A telltale sign that your brakes are going bad is leaking fluid. Remember when we mentioned that your brakes run on a hydraulic system? This means that the master cylinder that creates power for your brakes utilizes brake fluid to engage the brakes. When the brakes are engaged, the brake fluid travels through a series of pipes or hoses to create hydraulic pressure that’s evenly distributed across the brakes. Leaking fluid is a cause for concern since the system is unable to build enough power or pressure to distribute the fluid and engage the brakes. The result is a soft brake pedal and an unsafe driving situation.

#5 Soft Brake Pedal

When you engage the brake pedal, there should be some resistance. The pedal should not feel soft or spongy, nor should it be easily pushed all the way to the floor. This is a sign that your brakes need to be serviced immediately to determine if there are any leaks in the master cylinder or if there is air or moisture built up in the brake lines.

A close up shows brake fluid being poured into a car during a Nissan brake service.

Brakes 101: Key Takeaways

Now that you know how brakes work and how to tell when your brakes are bad, you’re probably wondering the best way to maintain your brakes and ensure their longevity. Here at Thomas Nissan, we’re proud to service your brakes, and part of that service means making sure you know how to take care of your brakes to ensure your safety on the road. That’s why we encourage our customers to have their brakes checked annually in addition to regularly checking the brake fluid. It’s also important to listen and watch for warning signs from those unusual odors, vibrations, and sounds.

You can extend the life of your brakes by making a few adjustments to your braking habits. Instead of forcefully applying the brakes each time you want to stop, you can preserve your brakes by coasting to slow down. You can also avoid using the brakes unnecessarily. We’re all guilty of following another car too closely and being forced to slam on the brakes to prevent a collision. This can be remedied, and your brakes can last longer by keeping a greater distance between the traffic ahead.