I have an '07 XK, there is an almost constant squeal coming from what I thiink is the brakes. I took it to the dealer and they did a complete brake job, under warranty. Unfortunately this not only did not correct the problem, it is now worse. What is odd about this is that applying the brakes does not change the noise. It is almost continuous. The only time it appears to stop is when I am driving over 50mph, but that might just be other noises drowning it out. Anyone ever hear of this? Looking for advice.

 

Could the electric park brake be partially stuck on ? This uses brake shoes in a drum formed as part of the rear disc.

Squealing can also come from the drive (serpentine) belt on the engine if the tensioner has failed, and also from worn pulley bearings on various items driven off the belt.

 

I have had this squealing noise for months. As I mentioned above the dealer did a complete brake job but this did not correct the issue. I discovered that the noise stops if I turn off the climate control system. I let dealer know and they discovered a refrigerant leak which, of course, caused loss of refrigerant. They repaired the leak, it was a bad fill valve, and re-filled the refrigerant. Probelm solved, PS, all under warranty.

 

I have an annoying noise in the cabin when braking. I wouldn't call it a squeal, but rather sounds more like a very rapid "chirping" noise, almost like some type of hyper bird or cricket. The amount of brake pressure doesn't seem to matter. It starts when I apply the brakes and stays at a constant volume until the car comes to a stop. It seems to come from the passenger side front part of the cabin. I'm due for a Mobil 1 change in less than 1000 mi, so I'll have it checked out then.