[therealm3]

I still fail to see how this "fix" works. The points of contact do not rotate and the squeal I have from 0 to about 15 or 20 mph is rotational. It sounds a lot like when I had HP+'s on my M3. My bet is as the sensor wears metal in it is contacting the rotor causing noise at slow speeds; or as another post mentioned, the hill assist could be causing extra drag. Or its just dirty parts that need to be cleaned and greased to retract properly when no brake force is applied. Could be all of the above.

[spool twice]

I can't get the rotor off to do this DIY after removing the caliper and the allen screw, anyone have advice?

[e90pilot]

Make sure the parking brake is off, use lots thread penetrator and go to town on it with a dead-blow rubber mallet.

[raceyBMW]

And if the above doesn't work, put a MAPP torch on it to heat it up and try again.

[E92_PINO]

Originally Posted by e90pilot

We all have disk brakes. The hand brake is a drum brake that uses the inside of the rotor hat as friction surface.

Thanks for the help! Mine hasn't gotten as bad as some I've read about but would like to tackle problem before it gets worse

[PBGF32]

OK.. former VW/Audi tech here. I'm having the same issue and have read over pretty much every related thread.

1. I'm absolutely sure it's not the sensors, there's multiple people running them zip tied away from the caliper and still having the issue so that eliminates them as the culprit.

2. For anyone claiming new pads have fixed their problem it's far more likely that having the braking system apart and back together has temporarily quieted the noise, but not solved the issue. This is illustrated with the many posts of "it was gone after new pads, but returned a couple months later."

3. Op's dust shield contact theory is decent however the noise is clearly rotational and varies with wheel speed. The contact point he speaks of is static without rotational effect and could cause a squeak, but would also be easily verified by simply pushing the car up and down.

4. This leaves the e-brake pads.. Many have stated that the problem is directly correlated to parking brake usage and I can attest to only having the problem after using my parking brake for the 1st time (auto). It seems obvious that the brake shoes of the parking break are ever so slightly dragging after the car gets hot (rotor expands from usage, but the inner hub were the parking brake shoes contact would actually decrease in size).

So the question I have is this: Has anyone tried simply adjusting the star wheel to pull the shoes away from the hub? OP stated his method has fixed the problem, but in addition to lubing the contact point he adjusted the parking brake star wheel. My money is on the star wheel adjustment as the solution, which would also explain why people have "fixed" the problem by having the dealership replace the entire braking system. In order to replace the rotors you would have to readjust the parking break and I'm 99% sure that is actually the wild goose everyone has been chasing.

[gatoracer]

Originally Posted by three35

OK.. former VW/Audi tech here. I'm having the same issue and have read over pretty much every related thread.

1. I'm absolutely sure it's not the sensors, there's multiple people running them zip tied away from the caliper and still having the issue so that eliminates them as the culprit.

2. For anyone claiming new pads have fixed their problem it's far more likely that having the braking system apart and back together has temporarily quieted the noise, but not solved the issue. This is illustrated with the many posts of "it was gone after new pads, but returned a couple months later."

3. Op's dust shield contact theory is decent however the noise is clearly rotational and varies with wheel speed. The contact point he speaks of is static without rotational effect and could cause a squeak, but would also be easily verified by simply pushing the car up and down.

4. This leaves the e-brake pads.. Many have stated that the problem is directly correlated to parking brake usage and I can attest to only having the problem after using my parking brake for the 1st time (auto). It seems obvious that the brake shoes of the parking break are ever so slightly dragging after the car gets hot (rotor expands from usage, but the inner hub were the parking brake shoes contact would actually decrease in size).

So the question I have is this: Has anyone tried simply adjusting the star wheel to pull the shoes away from the hub? OP stated his method has fixed the problem, but in addition to lubing the contact point he adjusted the parking brake star wheel. My money is on the star wheel adjustment as the solution, which would also explain why people have "fixed" the problem by having the dealership replace the entire braking system. In order to replace the rotors you would have to readjust the parking break and I'm 99% sure that is actually the wild goose everyone has been chasing.

I have been sub'd to this thread for a while now and been meaning to try the e-brake fix. I have to agree that changing pads and even filing down the shield will not help. I use my e-brake regularly (MT and do not leave car in gear when parked) and notice the squeaking pretty much daily. I even notice it when the e-brake is engaged. I can rock the car back and forth slightly, and hear the squeaking coming from the rear of the car. I haven't had a chance to get around to pulling the rear wheel off and inspecting. This Friday I have some maintenance items to do (spark plugs and cabin air filter) and I should have time to take a look at the e-brake adjustment as well. I'll try to remember to post my findings regarding the e-brake issue.

[spool twice]

This solved my brake squeal issue on acceleration from 0-20mph:



Before I used this, I too removed my pads and re-installed them to "re-seat" them on the caliper. The squeak when away until after the 5th time hitting the brakes. Mine was strictly limited to the passenger side rear, so I used the above and the squeal has been gone ever since. You just remove the pads, spray on the back sides of the pads (the side that seats to the caliper), wait 10minutes, and re-install. It apparently adds an extra layer to absorb resonance brake pads can produce when rubbing against the rotor. I have yet to test this long-term, but so far so good. I'm just happy my car is squeak free.

[PBGF32]

Originally Posted by spool twice

This solved my brake squeal issue:

Before I used this, I too removed my pads and re-installed them to "re-seat" them on the caliper. The squeak when away until after the 5th time hitting the brakes. So I used the above and the squeal has been gone ever since.

Ok so I'll bite on this, did you do fronts and rears or just the rears? Here's how I see this solving the problem. One, lets assume the hill assist is keeping the pads microscopically close or even touching the rotors for the first few mph's. If this is the case then I could see the pads (and their reverse and side surfaces) undergoing a fair amount of vibration due to the slight warping/surface inconsistencies most brake rotors naturally incur after normal driving. The CRC would lube up the noisy pad exterior and you'd be in business. ALSO it would explain why everyone has had temporary success with a new pad install. The simple act of changing pads would knock a lot of the residual brake dust out of the pad install area and the noise would cease.. 2 months of brake dust accumulation later and boom its back.

I'll have to do this over the weekend before adjusting the parking brake, it seems pretty viable aside from the rotational aspect of the squeak. Most of us have had it correspond to wheel speed and this would only be the case if the actual pad face was making the noise which is doubtful in my opinion. Although I suppose the frequency change could be attributed to rotor speed and how fast the pad rocks inside the caliper. While I'm in there can you guys suggest a pad for the e92 that ends this nightmare (less dust)? I haven't searched, of course, but imagine it's a pretty common switch. Thx in advance!

[spool twice]

Originally Posted by three35

Ok so I'll bite on this, did you do fronts and rears or just the rears?

Just the passenger side rear, my other brake pads don't make an ounce of noise.

Also FWIW, I originally thought it was the pad sensor, like some had suggested in other threads. Instead of buying new ones, I removed the sensor from the pad area to see if it fixed the squeal. It did temporarily (until like the 5th time using the brakes), but that's was only because you have to remove the pads to remove the pad sensor without destroying it.

[PBGF32]

Ok so I pulled the rear pads today and lubed all the contact points with CRC orange paste


Left the e-brake adjustment alone for now in order to determine if the CRC did the trick. After driving up to temp and using the brakes a similar amount to previous squeak inducing levels I can happily say the noise is GONE. I hit all the obvious parts of the outer surface of the pad as well as the clip contact points that hold the inner pad to the caliper piston with the CRC. There's absolutely no squeaking at any speed and the job took all of 45 minutes to do.

I'll report back after a few days, but the initial result is problem solved.

**NOTES:
1. There's a DIY for the rear pads that shows the removal of the caliper through the hex bolts on the rear side of the caliper. This is unnecessary, instead remove the dust caps that cover the 7mm allen studs and remove those studs completely. This will allow you to remove just the caliper instead of the entire mounting assembly.
2. If you're not replacing the pads with new ones then you won't need to worry about having a c-clamp or similar device to push the piston back into the caliper. They will come out a bit once you remove the caliper from the rotor, but you can simply push them back in by pushing against the inner pad and refit the caliper once you've lubed all the surfaces. I did this without removing the reservoir cap as well since I only had to move the piston a 1/4 inch to refit the same pads.

[raceyBMW]

Were your brakes squeaking on just braking, or were they also squeaking on slow acceleration up to ~10mph?

[PBGF32]

No squeal during braking at all. My issue was with the squeaky initial acceleration exactly like this video shows.

CRC paste fixed it completely. It seems counterintuitive considering the way the noise sounds in relation to wheel speed, but having the pads apart/replacing them has fixed the issue for many. The ones who replaced pads without using CRC ended up with the noise returning in a matter of weeks so I would highly suggest using it.

[JoshLee89]

Is there any way for me to apply "CRC Disk Brake Quiet" without taking off the wheels? I have done "On Car High Speed Balance" on my wheels, and I should not take off the wheels off the car.

Please let me know

[JoshLee89]

^^ So you must must take of the wheels?

[therealm3]

Originally Posted by JoshLee89

^^ So you must must take of the wheels?

Yes. wheels must come off and caliper needs to be unbolted (not the carrier).

[raceyBMW]

I had a pretty bad squeak going on from 0-10 or 15mph when taking off from a stop.

I needed new pads and rotors, and the brake sensors didn't come off without damaging them, so I replaced those too. I thought it might be the problem noted above, but decided not to mess with the parking brake and just replace the parts listed above.

In short, the squeak is completely gone after simply just replacing the sensors, in my case I am pretty sure it was just the sensors slightly rubbing on the rotor surface causing the squeak.

[marshall834]

This is excellent, excellent news. I've been dealing with this for the last several months and have torn the wheels apart, cleaned the rotors, pads, etc, re-seated everything, all to no avail.

I will try this next weekend with the CRC and report back. *Fingers crossed*

[Phil325i]

I replace sensors to cure the squeal, and it worked...for about a month!

I achieved a permanent cure by withdrawing the sensor, filing a little material off the end that rubs on the disc, and coating the shank of the sensor in copper grease. Peace restored!

[HoustonBMWClub]

any update on this? Wondering if the spray helped or its back to normal.

[DetectiveLoki]

I tried the CRC on my front brakes. It help reduced the noise, but still there when I make turns at low speed.

[E92murdered]

having same problem right now as well, where is the best place to buy rotors, brakes and sensors? do you also have to replace the backing plate?