Brakes Making Vibrations and Weird Noises

[TRZ06]

Originally Posted by ssabripo

** UPDATE No. 8934... **

Just got back from the dealer, and they installed the "updated" rotors/pads...no info on what kind of differences with the original set are there, but they say it was a new set that BMW GmbH is testing for this vehicle.

I will update you guys once the 500mile period is done, but at least out of the lot it didn't do the judder/vibration, and I did a quick bedding routine, and so far so good. It's been only a few hours so lets see what happens.


Note:
One thing I did notice is that the rotors have some very tiny elliptical grooves, which I didn't notice on the car when I first bought it. And I've had several drilled rotors, and never seen this, so perhaps this could be a clue into something BMW is trying?

see pics:

Did you verify with them that it is a new part number?

Because mine are being replaced as well , along with hub and bearings and they told me (just about 30 mins ago) all part numbers are the same and there are no revised parts, as I specifically asked that question

[mrduder]

Originally Posted by ssabripo

** UPDATE No. 8934... **

Just got back from the dealer, and they installed the "updated" rotors/pads...no info on what kind of differences with the original set are there, but they say it was a new set that BMW GmbH is testing for this vehicle.

I will update you guys once the 500mile period is done, but at least out of the lot it didn't do the judder/vibration, and I did a quick bedding routine, and so far so good. It's been only a few hours so lets see what happens.


Note:
One thing I did notice is that the rotors have some very tiny elliptical grooves, which I didn't notice on the car when I first bought it. And I've had several drilled rotors, and never seen this, so perhaps this could be a clue into something BMW is trying?

see pics:

Yeah mine came with that. It goes away after a few weeks of normal driving.

[TRZ06]

Originally Posted by mrduder

Yeah mine came with that. It goes away after a few weeks of normal driving.

+1

When they replaced mine the first time, it had those grooves in it as well.

I do not think it is a revised part, unless it has a new part number.

Mine has been escalated to the regional rep. , and according to him , there is no new parts at this time.

[TRZ06]

Update

My hubs and bearings were out of spec.

Let's see if the was the real issue or not. Guess I'll find out within 1000 miles.

[Tomm3]

Never tracked my car however slight vibrations started to occur when braking from higher speeds with hot brakes.
My thoughts, however I may be wrong, are that it's not a pad issue but a rotors itself.
When hot - they slightly bend somehow and vibrate, but when I cool them down - there are no vibrations any more. If it's a pad deposit it should vibrate at any temperature?
I will take my car for a high speed braking maybe tomorrow and will share my observations with you.

When brand new I performed the bedding procedure - 10 gentle brakings from about 120km/h to 20km/h to warm the brakes and then 10-12 hard brakings (almost until ABS) the same speeds and then 20-25 km of cruise to cooldown brakes. No vibrations at all that day.

[lpshikhar]

Originally Posted by jritt@essex

Thank you. Yes, I/we (Essex) are a paying vendor. We also have a staff with hundreds of years of brake experience. I'm sharing my nearly 15 years of personal experience in the racing brake business. If you look up the user name JRitt on any forum, that's me. I've used the same screen name since 1998 on various automotive forums. I've helped many thousands of people with brakes over the years. If people understand the underlying mechanisms of what's going on with their brakes, it will help them diagnose and remedy problems on their car. If they fix their problem, they enjoy their car more. To me as an enthusiast, that's what it's all about. If people want to come to us and purchase a solution and/or value our experience, that's great as well and we appreciate it.

Yes...you absolutely could be correct. For cars that aren't seeing track use, it could be just as simple as an incompatibility between the particular OEM pads and iron discs being used. I can't tell you how many times during my career we've had a customer run the same pad on different cars, and tell us that the results were different. The most common issue is noise. For example, a customer runs Ferodo DS2500 in their M3 and like it. They put it in their STI. The pad was silent in the M3, but is squealing in their STI. Another example...customer is running DS2500 on their OEM M3 discs. They buy a Brembo blank replacement disc, and now they're getting judder and vibration after they bed the discs in. The scenarios above occur constantly. Sometimes discs and pads just don't play all that nice together. While pads and discs look like simple hunks of metal, there's a lot going on behind the scenes.

A particular brake pad compound may frequently have as many as 20 different materials in them. These are typically brought together from over 250 potential raw materials the pad manufacturer has on hand. That is a lot of potential combinations!

Iron brake discs are also alloys, meaning that two or more metallic elements are combined. They aren't a single 'ingredient.' That's one of the reasons why a proper racing brake disc is far more durable on track than an OEM disc. It has to do with the metallurgy, not just the design elements.
Read this paper on brake disc iron if you want your brain to hurt.

So with pads and discs, you're taking a laundry list of ingredients, rubbing them against each other, and heating them up to ridiculous temperatures. The friction interface (pad against the disc) is an area of constant and intense study. We have a brake dyno that we use to test materials with AP Racing discs every day. The pad and disc interface also constantly plays out on our patented brake bedding machine. One of our brake pad suppliers has 34 brake dynos in their primary development facility in Germany...34! They're constantly assessing the interaction of the disc and the pad. There are a HUGE number of variables involved in how they react with each other.

So what happens if BMW uses one supplier for brake pads, and another for discs? Are they guaranteed to interact perfectly with each other? No. What happens if BMW's disc supplier gets a batch of raw materials from a different supplier, and those materials weren't identical to the last batch the disc supplier used to produce the first run of discs? What happens if BMW switches disc suppliers after the first model year? All bets are off in all of the above scenarios. Again, sometimes it really is just as simple as some type of material incompatibility. Most of that is caught during extensive testing. That's why OE's test, test, and test. Sometimes not every scenario is captured however.

The simple solution/path of least resistance is to first try different pads OR different discs. My recommendation is to go with pads, which is why I posted the links to the Ferodo pads. Pads tend to be cheaper than discs, and there are more options for preferred feel, heat range, etc. depending on the driver's needs/wants. That solution will also likely be the least time consuming, least nerve wracking, and least expensive.

The more complex, time consuming, and expensive option is to endlessly pursue your local BMW dealer and or BMW corporate for a solution. The problem is, this stuff is outside of their wheelhouse. Pad compounding scientists don't work at car dealerships, and there are 17 layers in BMW corporate that you'll have to navigate before you find someone who will have the knowledge or power to actually do something for you. The dealership may eventually concede, and your pads and discs are replaced at no charge. If the situation really is one of material incompatibility however, the problem will not be solved. It will eventually just happen again, assuming you are driving the car in the same manner. Definition of insanity right?...there would be no reason to expect a different result using the same pad and disc compound under the same conditions. However, if the pads and/or discs are in some manner different than the set you had previously, you could be in business. There's unfortunately no way to know that however.

I do get it though gents. I've been there (see my 350Z comments below). Having things be less than perfect sucks. When you buy what is supposed to be the best and drop $80 large of your hard-earned coin, you want a flawless experience. I just want people to understand that the pad and disc interface is a complex issue, and that there are many variables involved. In the car manufacturers' defense, they do instrumented testing on everything imaginable, and they really do want their product to be flawless. However, to quote the wise John Bender, "Screws fall out all the time...The world is an imperfect place." Fortunately, the issue under discussion isn't one that causes catastrophic engine failure like past generation cars. It's unfortunate, and each person has to decide what their ultimate goal is and act accordingly. Do you just want the problem solved? Do you want a simple apology? Do you want to make someone pay for your inconvenience? Do you want BMW to collapse for their sacrilegious transgressions against the M badge of honor? I'm obviously exaggerating, but you get the point.

Xtabi....I owned the 399th 350z ever produced out of Japan...I remember the good 'ole days on my350z.com and the endless 'tire feathering' threads. I ended up getting a new tranny for that car under warranty...I think they were on revision 7 or 8 at the time. I don't remember it being easy or fun...Doh! New model blues.

Very informative.

[FLOSS M]

I have noticed the same issue from day one with the stock pads. I do track and go back and forth between stock and rs29 pagids... I just live with it. like others have said it will come back again anyway

[WhitehawkCS]

i know this may be a little old to post, but the groaning noise was out of control on my car. between 55-40 mph braking, i couldnt keep a conversation with anybody in the car. i had the dealer change the pads, but its the compound bmw is using thats making it miserable.

i changed the pads this past weekend to the posi-quiet semi-metallic. the noise is completely gone, but there is less "bite" with the brakes now. although it doesnt bite as well, i must say its much more pleasurable to drive due to the lack of noise and vibration in the brake pedal.

i'm hoping somebody comes out with some pads that keep the bite but get rid of the noise, but until then, i feel this is the way to go for street driving.

[TRZ06]

Originally Posted by SymphonyM3

i know this may be a little old to post, but the groaning noise was out of control on my car. between 55-40 mph braking, i couldnt keep a conversation with anybody in the car. i had the dealer change the pads, but its the compound bmw is using thats making it miserable.

i changed the pads this past weekend to the posi-quiet semi-metallic. the noise is completely gone, but there is less "bite" with the brakes now. although it doesnt bite as well, i must say its much more pleasurable to drive due to the lack of noise and vibration in the brake pedal.

i'm hoping somebody comes out with some pads that keep the bite but get rid of the noise, but until then, i feel this is the way to go for street driving.

I'm very baffled by this. BMW had a compound in the E90/92 M3 that had both stopping power and quiet , no vibration.

Why can't they go back to that??

[CanAutM3]

Originally Posted by ssabripo

Note:
One thing I did notice is that the rotors have some very tiny elliptical grooves, which I didn't notice on the car when I first bought it. And I've had several drilled rotors, and never seen this, so perhaps this could be a clue into something BMW is trying?

The cross hatch pattern is normal and has always been there. It is present to accelerate the bedding of the pads.

It is mentioned in the Brake Systems: Deep Dive and Interview (see caption below).

[WhitehawkCS]

because they're idiots and think BMW can do whatever they want and we just have to live with it.

when i first got my car in april, i didnt have any issues at all.. then the rotors warped in 4k miles and they changed out the pads and rotors and then thats when the problems started.

get the posi-quiet semi metallic... they are like $50 from carid.com.

[andrej--h]

Hi community. This shity brakes on my 2016 F83 drive me crazy. It started all with 22tkm. On Autobahn with some fast stages and hard breaking this affect appears more an more frequently.

Well somehow it getting that horribly that passages are thinking they gone die because brake will fail. It drones and the car vibrate at speed above 140km/h. The surface of the rotor look imo very accurate with blue color or inperfections. Cars is Switzerland has 3 years warranty. do you think it is worth to start the discussion with BMW? Or just to go for aftermarket solution? Car has today 33000tkm all stock and BMW dealer maintained

[rich8566]

I was not going to jump in here, but here it goes anyway. I have an M2. I ruined my brakes in just two track days using my stock pads and rotors on track. I ended up with a horrible warped rotor condition. Braking was lumpy, jumpy and terrible. I changed out the OEM pads with track pads. In between track days I used the track pads on the street. I was told that using track pads at relatively cold temps would help scrub the OEM pad material off of the rotors. Then after a couple of additional track days my lumpy, jumpy, "warped" rotors were like new again. Smooth, and nice and not lumpy or jumpy.

Then this past weekend I swapped out the track pads for the OEM pads. And low and behold, the braking action is super smooth and not lumpy or jumpy. . Problem solved.

[andrej--h]

Had again a case where the brakes began to vibrate. Went straight off the Autobahn and shot some pic of the rotors.

You can see all the pad compound even filling the holes. You could stripe it off with the finger.

[andrej--h]

After discussion between dealer and BMW SWITZERLAND they announced to replace all 4 rotor and pads. On top they found some suspect spec at the left front bearing-hub. So well, dealer wanted to apply the material. But last minute BMW SWITZERLAND rejected. Since they saw on my car I had installed before some EIBACH spacers.

I am bit shocked about the fact having a 2 year young performance car without proper brakes.
Car has nearly 35k km and seen never a track.

Will now investigate the issue closer. Had already a call with HQ support Hotline in Switzerland . Person was nice and calm promised to feedback by mail. Will update later

[Djf80]

I know this an old threat, but wanted to add my experience. I had severe break judder after track days with Oem pads and steel rotors. After no significant improvements rebedding the breaks and a few weeks driving, installed pagid yellows (27) pads and drive for a few days. They are loud and will only use on track. However, judder gone after replacing with original pads. Hope this helps.

[Evren]

i have the same problem. just friction voice when its high temperature condition. i dont know but maybe its normal because of the alloy. but no vibration.

i felt it better after 20 minutes fast track time. then i checked my brake shoes and some piece was burned.

also my friend had the same problem with his 4000 km car.

you can buy carbon ceramic brakes if you can.

[mynameisplayer]

I've got the judder and groan - 9000km car never tracked. Put it on the hoist and measured run-out with a dial - .1mm lhs, .2mm rhs. Does anyone know BMWs allowance?

[TRZ06]

I think BMW quietly changed the compound on the brake pads.

I have had the issue twice and had the rotors / pads replaced twice under warranty.

Just had my 30k service done and the vibration had been back for a while.

I Complained about it and was told "can not reproduce issue", however when I got my car back, the pedal felt much firmer and the pedal engaged the brakes a lot sooner.

They obviously did not change the rotors and made no mention of doing anything on the paperwork but it sure feels like there are new pads on it. , The vibration is completely gone. I'm still get a little growling sound, but no vibration.

I think they quietly changed the pads.

UPDATE:

800 miles later, still no vibration. I get the groan sound still, but smooth.

They DEFINITELY updated the pads on my last visit. They are very sneaky.

[Roch M4]

I've had a similar issue after BMW replace the back plates behind the rear rotors under a recall procedure (car was having 20 000 km). Shortly after the replacement, which included new rear bearings, a noise and vibration appeared when braking at 80 to 120 km/h. The car is now at the dealer, they find out that the rear rotors are twisted and they will replace both of them...