Grinding Noise when braking?! Help!

[misslauriet]

Sorry if any of this has been posted before but nothing came up in a search on the forum.

This is driving me absolutely crazy. I know next to nothing about cars (i'm a woman, it happens), which makes it even worse.

Around 68K miles, my 08 Mazda3 started shaking/vibrating when I would brake. Boyfriend took it in to a mechanic (not a Mazda dealership) to have the front rotors machined/resurfaced, and they replaced my rear brake pads and shoes (ceramic). They supposedly inspected the entire brake system and changed the brake fluid as well. Afterwards, everything was great, no more vibrations/shaking, and quiet, clean braking.

Well, about a month later, I noticed a weird grinding noise in the rear of the car of every time I hit the brakes. It's really REALLY loud and annoying... but the weirdest part is that for a while it wouldn't show up all the time. Now it is ALWAYS there. It is the most annoying thing in the world and people in other cars stare at me when I'm braking. *cringe*

I haven't been able to get a video or anything of how it sounds, but it sounds pretty much exactly like these:

http://www.youtube.com/watch?v=_KvcvM7hhjI&feature=relatedd

http://www.youtube.com/watch?v=x7EG-87cVvY

Unfortunately none of the people on Youtube offered a viable explanation to those videos.

I just really want to get a sense of what's truly wrong so I know how much money I will need to shell out for this.

Any help will be greatly appreciated!!
xoxo

 

[njaremka]

jack the car up, pull both rear wheels off, and inspect the condition of the brake pads.

 

[WillD]

Well, first things first... welcome to Mazdas247!!! (2thumbs)

It doesn't sound to me like you want to get under there and investigate the problem yourself and if that is the case I think you should take your car back to the shop that did the work as soon as possible and have them identify what they think is the problem. Throw whatever type of fit is necessary to get them to at least look at it for free. Unless something broke, your brakes should be functioning perfectly only a month after service and if something did break I would be willing to put money on it that the mechanic did something wrong.

Are you absolutely positive the sound is coming from the rear of the car?

Did the car bed the brakes in properly? (If you don't know what that means this article will give you more information than you ever will want to know about bedding. )

Has any service been done to the front brakes? Usually when there is a vibration during braking I'll look to the front brakes as the culprit. And, I would insist on new rotors next time you take your car in to fix a vibration related to braking. You can always ask the shop how much it would cost for new ones and often times it will be cheaper than resurfacing, especially with the 2.0L Mazda3 and the small rotors it has. But I find it strange that they replaced the rear brakes and didn't do the front. My fiancee has a 2009 3 with about 60k miles and her rear brakes are no where near needing to be replaced.

 

[MudderMazda]

Definitely have the bearings checked!