How to Tell If Rotor is Bad?

Like other mechanical parts of your car, brake rotors are of utmost importance and play a crucial role in bringing the car to a stop. The brake rotor is a disc made of metal alloys …

Symptoms of a bad rotor

Like other mechanical parts of your car, brake rotors are of utmost importance and play a crucial role in bringing the car to a stop. The brake rotor is a disc made of metal alloys and works in harmony with the brake pads and brake callipers to provide adequate stopping power to a vehicle.

Brake rotors are among the parts that undergo continuous wear, just like tires and brake pads, and need to be checked constantly for any damages. They use friction, by bringing the brake pads in contact with the rotor and are one of the most rugged parts.

As a car owner, you must be aware of the symptoms and signs of bad rotors so you can get them fixed if a problem appears. Bad rotors are notorious for producing weird noises, reducing braking efficiency, and creating vibrations in the car.

In this article, we will discuss what do bad rotors look like, an insight into good rotor vs bad rotor, and how you can check it for damages yourself and get a replacement.

What are the Different Signs of Bad Rotors?

If you’re wondering what do bad rotors look like? There are some evident signs that a damaged brake rotor shows. You must keep your eyes and ears open for these signs;

Squeaking Noise from Brakes

A worn-out or warped brake rotor would not have proper contact with the brake calliper and wheel hub. Once you apply brakes, the brake pads would rub against an uneven rotor and create squeaking or squealing noises. You would notice these noises when braking at high speeds, or bringing your car to a stop.

Vibration on Applying Brakes

A damaged or cracked rotor would vibrate when brakes are applied. These vibrations are felt in the brake pedal, as well as the car’s body. Warped rotors are prone to vibrations and pulsations, especially if the brakes are applied a little hard.

Reduced Stopping Efficiency

Needless to say that if the brake rotor is damaged or worn badly, it would not be able to stop the car properly, and the stopping distance would be increased. Brake pads and callipers fail to make optimal contact with the rotor and hence, the reduced efficiency of brakes.

Stopping Distance Increased

If you’ve noticed that your car takes longer to stop than usual, there’s most probably a bad rotor underneath. There’s no rocket science here, a bad rotor would fail to bring the car to halt optimally and it would travel farther to come to a stop.

Evident Cracks on the Brake Rotor

Small cracks start to appear on the brake rotors as they undergo significant temperature changes and bear the grunt of the stopping power. If you notice a crack or even small crack lines appearing on any of your brake rotors, it is the most evident sign that it needs replacement, as there’s no fix for that.

Over Responsive / Under Responsive Brakes

If your brakes are responding weirdly, for instance, stopping immediately on pressing the brake pedal or taking too long even after flooring it, suspect a bad brake rotor. No matter how quick or late the response of your car’s brakes is. If it is not optimal, it is abnormal and could be a sign of a bad rotor.

Strong Burning Smell

When an unevenly surfaced brake rotor is used frequently, it generates extra heat and reaches unprecedented temperatures. Not only does this release strong chemical fumes but also a particular burning smell as well. If you’ve noticed this smell only after applying brakes, suspect a bad rotor.

Checking Brake Rotor for Damage – Step by Step Guide

If you’ve noticed some problems with your car’s brakes lately, here’s how you can inspect the assembly and tell if the rotor is bad.

Step 1

Take your car for a test drive on a secluded road and look for the signs of bad rotors we just mentioned.

Step 2

To test the brakes, accelerate to 35 mph and apply brakes abruptly. If the brakes produce a squeaking noise or the brake pedal vibrates, your suspicion was right. Test again by accelerating up to 60 mph and applying brakes instantly. The car would vibrate, take longer to stop, and even emit that strong smell if the rotors are damaged.

Step 3

For visual inspection, park your car on a levelled surface and engage the parking brake. Using a jack and jack stand, raise your car a couple of inches above the ground.

Step 4

Loosen the nuts on your wheel and remove it, then undo the brake calliper with the hand wrench and remove the brake pads. Inspect the brake pads and callipers for any warpage or uneven wearing pattern.

Step 5

Now inspect the brake rotors one by one and look for uneven surfaces or any evident damage. Look on both the inside and outside surface for any pits, rusting, or crack lines. It is also important to note the alignment of rotors with the wheel hub and the overall thickness of the rotor in micrometres. Usually, it takes years for a rotor to wear off, but a bad rotor wears off at an accelerated rate due to warpage and increased temperatures.

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FAQs – How to Tell if Rotor is Bad

Q1- Is it advisable to use new brake pads on bad rotors?

Using new brake pads on worn-out rotors would only add to your misery. No matter how good the pads are, they won’t be able to make normal contact with the rotor and get damaged quickly.

Q2- When should I replace the brake rotors on my car?

It is advisable to replace your brake rotors every 75,000 miles or so, and ideally get them inspected every 10,000 miles.

Q3- How much does the brake rotor replacement cost?

A pair of brake rotors with labour charges could cost you up to $300. This is the average price for passenger cars and could be much higher for heavy-duty vehicles like trucks or buses.

Q4- Should I keep driving with bad brake rotors?

It would be very dangerous to keep driving with bad rotors as you could lose braking power at high speeds and put your and others’ lives in danger. As soon as you sense a problem with your brake rotors, get them replaced.

Q5- Common reasons behind bad brake rotors?

1. Rash driving

2. Abrupt and heavy braking

3. Not replacing the brake pads timely

4. Driving mostly on uneven surfaces

5. Not getting the brake callipers serviced on time


Brake rotors are the platform on which your car’s braking assembly is based. These are usually very robust and last a long time before showing any signs of ageing, but could go bad well before that due to certain reasons.

Bad brake rotors present as squeaking brakes, a weird burning smell on applying brakes, vibrating brake pedal, and reduced brake efficiency. As soon as you notice any of these signs, get your brakes checked for any damages.

Mostly, there is no repair for warped or damaged brake rotors and replacement is the only sensible way out. You should drive your car carefully, replace the brake pads on time, and get the brake assembly serviced regularly to ensure the longevity of brake rotors.