Mystery Noise

There is an occasional noise that happens only when I am braking my 2003 Corolla. My mechanic has ruled out the brakes and says there is nothing apparent that would make it dangerous to drive the car. The noise has happened on hot days, cold days, dry days, rainy/snowy days. It doesn’t happen each time I brake. When it does occur it ranges between a sound like a humpback whale’s song to a very loud screech. When it does, it is always right before the car comes to a stop. It happens when I back up and when I am going forward. I cannot reproduce it (I drove with my mechanic all over heck and gone trying to get the car to make the noise, alas, it would not). However, I did capture it at its loudest. Take a listen.

Any ideas??

This is the sound.

Have you had any brake work done on your '03 Corolla? If yes, the pads used maybe “hard” and now have a glaze on them. That can set up a “harmonic” at low speed just before you stop.

If no, this might be your worn pads chattering, or moving, in their clips which are now old and have lost some of their spring.

Either way, this is a brake problem that could be resolved with a good dose of brake cleaner. If nocleaning doesn’t do it; you might need a brake job meaning new pads and possibly rotors.

Can you tell if this is coming from the back or front? It is likely from the front, I believe your Corolla has drum rear brakes which are less likely to produce this kind of noise.

Solution could also be as simple as applying brake pad grease to the back side of the pads.