CAR: 2004 Mini Cooper S, Manual

Hey all,

I've got a squeal coming from my brakes that I cant seem to pinpoint. At first I thought the brakes were sticking because it would squeal while accelerating from a stop. Now I'm just confused because it squeals intermittently but not really when I'm braking. On the highway is when I hear it most because I'm usually driving with the windows down, and it isn't like a brake squeal, as it's much higher pitched, almost like a whistle, and less like a pad and rotor grinding.

Brake pads will need to be replaced soon, but I dont see that as being the culprit. Anyone have any suggestions as to where to start?

EDIT: Also, to note, when i brake, it seems the squeal stops momentarily then nearly immediately after i let off brakes and cruise/accelerate, the squeal comes back. I get this at both low and high speeds, regardless of ambient/engine temperature.

Thanks,
GP

 

Try washing the brakes with a pressure washer, it may have something caught in them (sand, debris, dust). My Sprinter does that when we drive down dirt roads sometimes.

 

Reminds me of when my throw-out bearing started sounding like a whistle when clutch pedal not depressed. When you accelerate the throw-out bearing is spinning faster making more noise. Does it happen when clutch pedal is depressed?

 

probably something caught - check the rotor, see if there's any marks on it

 

I am having this same issue. I picked the car up in december progressivly squeeled into winter and the pads had 75 percent life and same with rotors. i replaced them anyway. I got a solid 6 hours of ear relief and then it has been getting worse ever since. and the rotors were cleaned with soap and water and pads were properly bedded. does youtr squeel change pitch when you apply the brakes?

 

If it's the brakes, you need to determine which wheel is the culprit. Then safely jack up the car using jackstands and take off the wheel. Use a good flashlight while rotating the hub. Look for a pebble stuck in between the brake splash shield and the rotor. Check the pads for wear down to to the backing plate, especially on the inner one which is harder to examine.

 

Thanks all for your input, haven't had time to work on this as I've been moving my stuff out. Hoping to work on this in the next weekend or two so I will keep you all posted. To note: the sound is strongest from the left side of the car (when I'm driving next to a highway median, as it reflects the sound).

No, the car could be rolling, with clutch pressed or not and it would still sqeaul.

No marks on the rotors... Except for a hairline on the front left (which is where it sounds like it's coming from). I'll inspect it more this weekend, as I haven't had any chance to.

It's silent when I press the brakes. I only get this noise when I've let off the brake and started accelerating or have been cruising on the highway.

I'll definitely do this within this weekend or next, considering the hairline sized line i see on the front left rotor.