[AcExSpades]

Hi guys,

I've started hearing the annoying brake squeak about 3 weeks ago thinking that it was my front brakes as my rears were changed last July(for squeaking while reversing). Well, I took it to the dealership for this and many other issues. They changed my oil, wipers, filled fluids, but said that the brakes cannot be changed as they are still good and the noise is normal for BMWs.

I took it to the same dealer 2 day later asking to take a drive with the shop foreman so he can hear it. At first the tech was hesitant, because records showed that my brakes aren't due yet, but he agrees and off we go. While driving, of course my brakes weren't squeaking for jack but on the way back to the dealership they started squeaking and he hears them.

We talked inside for a while until finally telling me that they will be replaced. I was very happy as I thought this chapter was going to be closed and after a couple hours I went back to the dealership to pick up my car. On my way home I heard no noise, but later on that day the dreadful sound was back

What could be the issue? Is this noise really not going to go away? I thought for sure it was the front brakes.. I would say the rears, but as stated they were replaced last July. Any advice guys? It is really embarrassing to hear this type of noise on a car like this.

[IN54NITY]

Hi. You must be new to BMW..... Welcome to squeaky brake country.
1) http://www.e90post.com/forums/showthread.php?t=76418 and search for "CRC Disc Brake Quiet to make sure" in that thread.

2) Go out on an empty highway and brake very hard (just at verge of ABS) from the speed limit (say 65 mph) down to 5-10 mph ~without~ coming to a complete stop, 6 or 7 times - this is called "bedding in" or "seasoning" the brake pads. Then drive a while longer to allow the brakes to cool, before you come to a complete stop, and especially before you park it for the night. You ~don't~ want hot brake pads on their motionless rotors, this could possibly warp a rotor or leave too many deposits on (a) rotor(s). This process isn't really necessary for you, but I noticed that when I brake softly for a while (street driving on street or highway) that my brakes squeel more. After a good session they seem to stay quieter for a week or two. http://www.stoptech.com/technical-su...ake-pad-bed-in

3) If that DIY thread didn't scare you off, you may try chamfering the front "leading" edge of the brake pad with a file. http://en.wikipedia.org/wiki/Chamfer http://www.aa1car.com/library/2004/bf80426.htm and a good pic: http://www.aa1car.com/library/2004/elements/80426c.gif

4) Take off the pads and inspect (you did that to chamfer or put CRC Disc Quiet on anyways), make sure the brake pad sensor is put in correctly - it may make squeaking sounds. In my '09, the brake pad sensors were on passenger side rear and driver front wheels.

5) Some other posters will say change pads. IMO the stock OEM pads are great for street driving, they have terrific cold temperature torque.

6) Turn up the music.

[AcExSpades]

I was actually reading about the "bed-in" process.

I tried it and drove around for a while today with no squeaks.

Hopefully it stays that way, otherwise i'll try other options.

Thanks!

[achien]

I have got a better idea, minimize the use of your brakes by using more engine braking...

[OG Ryder]

I am the only one around here that thinks there is a problem with just "accepting that BMW brakes sqeal"

Brakes shouldn't make noises!

[AcExSpades]

Originally Posted by OG Ryder

I am the only one around here that thinks there is a problem with just "accepting that BMW brakes sqeal"

Brakes shouldn't make noises!

I agree 100%, as I said before BMW's shouldn't do this.

Now back to topic, my brakes started squeaking again .

I do now realize is the brake dust that gets into the pads. Can any compound be put onto the pads for this to be reduced? I'll see if i can get a shop to look at this leading edge.

[r3dbimmer89]

I'm starting to think it has something to do with the e brake.

[AcExSpades]

Originally Posted by r3dbimmer89

I'm starting to think it has something to do with the e brake.

Please elaborate..

[r3dbimmer89]

Originally Posted by AcExSpades

Please elaborate..

Quote:
Originally Posted by nOshi
"Same story, as everyone. I even took the sensor off and the noise is still present. My sensor is located on the passenger side rear, and driver side front This past weekend I wanted to find a fix, the noise makes driving this car no fun. Ironically when I was loosen the rear bolts before I jack the car up, I heard the noise. My car was sitting in the garage for a day, and wasn’t moved. I was surprised since the noise will occur after a few miles of driving or so. Since the car rocked a bit from when I was loosening the bolts. I found the noise was coming from the driver side rear, somewhere in the brake assembly. I pulled the hand break up and then back down and tried rocking the car again, and the sound was gone. It seems it might be an issue with the handbrake pad on the rotor not disengaging correctly or sticking. I had to go somewhere so I wasn’t able to look into it anymore. I’m going to check the hand brake pad, when I get sometime.

One thing that I noticed is if I put the car in neutral, and then back to drive. When I move off the sound will not occur, until I step on the brakes and release it again. I tried placing it in park and then in drive and it will yield the same results."

You're right. I noticed that sometimes when I forget to disengage my parking brake while backing out of my garage the sound goes a way for a while. Then it slowly comes back after driving for a while. I'm thinking it has something to do with the E brake. As you all may have noticed the same squeak is there when you get in and out of the car, when parked, and the e brake is engaged. Even though my E46 squeaked with the e brake engaged in park it definitely did not squeak while rolling from 10-20 MPH. I love this car but I'm really getting sick of this damn squeak and it makes me want to run and get a F30.

[crypticc]

I have had my car from new since 2007 and still have original brakes after 24 o (I drive infrequently, smoothly, but hard). Never a squeak except a brief chirp on set off immediately after a hard stop.
Have never heard anything so ridiculous as to accept squeaking brakes. Had that on my first car, a Fiat uno for f sake.

Is it while applied, or always? If always it means a caliper or cylinder outta ceased. End of.
If applied, bed them in as others have said but go easy for couple of hundred miles

Best of luck.

[darkw1sh]

HATE THE SQUEEKING BRAKES dealer told me its from hillside assist which apparently stays active until 18 mph

[eforty6_m3]

In for further updates...

[r3dbimmer89]

Originally Posted by darkw1sh

HATE THE SQUEEKING BRAKES dealer told me its from hillside assist which apparently stays active until 18 mph

Hmm I dunno about that since this problem seems to be isolated to 335i's and 330i's. If that was the case then 328i owners would be complaining about the same thing.

[darkw1sh]

Originally Posted by r3dbimmer89

Hmm I dunno about that since this problem seems to be isolated to 335i's and 330i's. If that was the case then 328i owners would be complaining about the same thing.

Correct me if im wrong didnt the 328i get Hill Start assist only on 2012?

I maybe completely wrong so please correct me.

[r3dbimmer89]

Originally Posted by darkw1sh

Correct me if im wrong didnt the 328i get Hill Start assist only on 2012?

I maybe completely wrong so please correct me.

I'm pretty sure all US E90s came with Hill Start since 06. It's part of the whole DTS+DSC safety combo.

[grandmaster]

Originally Posted by darkw1sh

HATE THE SQUEEKING BRAKES dealer told me its from hillside assist which apparently stays active until 18 mph

This sounds very plausible.

I've noticed the sound is present at low speed, then once you get past a certain speed the sound disappears. Almost like the caliper is keeping the pads on the rotor/disc at low speed, then releases once you hit a predetermined speed. Maybe it's a safety feature, or a flaw in some software. I always had a suspicion it was something to do with the stability/anti skid, or even the ABS system. Or, it's the emergency brake system - which i know nothing about.

Also, and this should be made clear to others who are reading this thread, the noise is present when you aren't applying the brakes. Maybe i'm completely wrong and dont understand brakes, but i dont think bedding them is going to do anything for this problem.

The problem is a squeal while NOT applying the brakes... and the bigger question of why is the brake pad, on the right rear wheel only, touching the rotor at low speed, and only when the car has been driven for awhile? I assume some safety feature is keeping the pad very close to the disc, and after driving a bit, the disc heats up, expands, and rubs against the brake pad at low speed due to some feature.

[darkw1sh]

Originally Posted by grandmaster

This sounds very plausible.

I've noticed the sound is present at low speed, then once you get past a certain speed the sound disappears. Almost like the caliper is keeping the pads on the rotor/disc at low speed, then releases once you hit a predetermined speed. Maybe it's a safety feature, or a flaw in some software. I always had a suspicion it was something to do with the stability/anti skid, or even the ABS system. Or, it's the emergency brake system - which i know nothing about.

Also, and this should be made clear to others who are reading this thread, the noise is present when you aren't applying the brakes. Maybe i'm completely wrong and dont understand brakes, but i dont think bedding them is going to do anything for this problem.

Correct, the squeeking actually goes away when you are on the brakes... I looked into it and it does look like it is the "hill side assist" feature. BOOO!

[psmitty95]

Well my brakes squeak when coming to a stop but that's cause i think i need new brakes in the front. For those of you who hear the squeaking from driving have you seen this?

http://www.e90post.com/forums/showthread.php?t=697365

[Kayani_1]

I am also experiencing this same issue of brake squeal at low speeds. On the E90 forum here I have seen multiple threads with this issue. I think BMW needs to man up and do a recall on these brakes and fix the issue for once and for all.

As there are way too many 335i's that are suffering from this design and material flaw of the OEM brakes.

Maybe BMW will only step up and do that if a mass law suit is filed much like in case of turbos waste gate rattle. Come on BMW fix this issue a over 50K luxury car should not squeal like a pig. It is embarrassing when a BMW sounds like a dump truck while braking.

[dinkoh]

Any updates? Why does it squeel at around 20-25mph? It's not constant either....

[BIFCAIDS]

Hmmm mine are squeaking but it could be something to do with the fact I need to replace them soon, but never the less it only ever happens if Ive not used the car for a day and for about 10 yards then doesn't do it again at all.

As for the pads being low does anybody have any information on what pads I need for the rear and Im right in thinking I need a new wear sensor?

Cars a 2008 325d m-sport.

[PTek Will]

This brake squeak is not actually the pads. This squeak that everyone is complaining about is coming from the hand brake. However, it is not the actual braking motion of the hand brake. The hand brakes are drum brakes. The cause of this problem is the way the shoes are seated and they actually rub against the side retaining plate (don't know what it's called). To fix this the rotor needs to come off and the shoe needs to be removed and you will see that the retaining plate* has a few contact points with the shoe. These contacts points should be scraped down to the metal, or rusted. File these areas down and grease them up really well. This should fix the squeaking noise.

Here's the link to the guy that found out how to fix it:

http://www.e90post.com/forums/showthread.php?t=697365