This may be something a simple as dirty, crudded up pads and rotors, but that traditionally has produced high and loud squeals. Hissing sound forces me to the vacuum booster or some part of the brake system leaking vacuum. That would worry me a lot. I wouldn't drive it very much until you can get a tech to look at it and diagnosed.

Rick

 

Thanks I thought of that too. It's been parked all weekend.

Since the dealer replaced the front brakes about a month ago it will definitely fall under their 'make sure it's correct' policy. Car will be there tomorrow night waiting for them.

 

Or possibly its the driveshaft. I had a whistling sound pop up everytime I took my foot off the gas back in October. Thought it might be something transmission related given the location of the sound, but turned out the driveshaft had to be replaced.

 

Got my Treg back tonite and they couldn't duplicate the sound. I actually had not heard it for a few days after I first noticed it. Maybe it was cold weather related. At any rate I will keep an ear posted and see if it returns - or gets worse. We'll see. Otherwise, I'm still gonna drive like crazy.

 

Got my Treg back tonite and they couldn't duplicate the sound. I actually had not heard it for a few days after I first noticed it. Maybe it was cold weather related. At any rate I will keep an ear posted and see if it returns - or gets worse. We'll see. Otherwise, I'm still gonna drive like crazy.

Is yours a 2006? I get the same thing is the cold weather and I believe there is a TSB covering this problem. I don't know the # (C-46-06-03?) but is has something to do with replacing brake pads to solve intermittent squeal.

 

It's a 2004 and I haven't heard that sound again since last week. It was occuring with the colder mornings, but only 3 or 4 times. And they already did the brakes a couple of months back so I think we're in the clear now.

 

... so I think we're in the clear now.

Spoke too soon. The sound is back. And the sound is more like a squeaky belt than anything else now. Occurs occasionally when I brake and also when I simply take my foot off the accelerator. Thinking it might be ... geez, no idea at the moment.

 

My car is an '04 V6.

I have the same whiste or whine you are talking about. I thought it was coming from my worn brakes but after I did a full brake replacement of pads, rotors, clips, springs and sensors. I still have the noise. It is not alway present but I can hear it at speeds up to 40mph while driving. I have also noticed that I get the noise when I turn the wheel in one direction but not in the other.(can't remeber the direction off hand)

First I thought it was a wheel bearing issue but my mechanic said there is not any play in the hub that he can detect.

I myself have been puzzled. Let me know if your dealer service department can detect and correct this noise permentantly.

I know it is brake related because If I take the pads out and switch the inside with the outside I don't hear the sound for the first 20 miles of driving. The Longest period of time the noise was gone for has been two days with driving short distances. I also notice that a line normally gets scored into the rotor face when the noise is loudest and most annoying but the pad swap gets rid of the line and the intensity of the whine.

It does not seem to be related to the pad material either because it happened when I was using ceramic pads and now stock formula.

 

I as well have the same thing going on, I believe it is the breaks. It happens while the car is moving, when I turn the wheel etc, the same as you are experiencing, I had my brakes done 2 months ago I almost feel it is the sensor they put on. Has anyone tried to take that off or can it be? Any hellp figuring this out is greatly appreciate it. It makes me want to drive off a bridge, its really annoying to listen to coming from such a beautiful car.

V8 2005
Thank you

 

It is definitely related to the brakes but it is not the sensors they don't touch the rotor face until the pad material is worn.

this is my theory:

The left front wheel has lots of torque applied to it so the force or the torque pulls the pad against the rotor and we get that whining sound.

I want to flush my brake fluid and bleed the system and see what happens. because it does not seem to happen to everyone's car.

Anytime I swap the inside pad with the outside pad they whining/humming stop for a couple of days.

I don't know if this may be a common issue with brembos since this is the first car I have owned with them.

Maybe the anti rattle clips/springs that hold the pads down get worn out faster on the left front position for the axle torque.