[Accentu8]

So, just purchased a new 2023 840 last week. The sales manager was using as a demo, had 180 miles on it. Up to 310 now. During test drive no squealing, but right after pick up squealing so loud can be heard from hundreds of yards away, super loud. It’s not too late to bed them? And really, up to 100 mph, then brake hard to single digits?? Going to be hard to find a good spot for that!

[Phili]

Originally Posted by fmzip

Saw this, had to share!

Now that is funny

[Accentu8]

Did the bedding procedure twice because after the first one, still squealing. Have tried going in reverse and braking hard as some have mentioned. Still squealing. I’m not talking slight squeak here, the sound is a VERY loud squealing. I had an Audi SQ5 that would at times give a little squeak or grunt. What I’m experiencing is not that. And it’s been warmer here, up into low 50s. Have an appointment Thursday.

I have sound clip. Wish I could post here.

[claykin]

Originally Posted by 23TripleBlack

Did the bedding procedure twice because after the first one, still squealing. Have tried going in reverse and braking hard as some have mentioned. Still squealing. I’m not talking slight squeak here, the sound is a VERY loud squealing. I had an Audi SQ5 that would at times give a little squeak or grunt. What I’m experiencing is not that. And it’s been warmer here, up into low 50s. Have an appointment Thursday.

I have sound clip. Wish I could post here.

Please let us know how your service appointment works out.

[M8Bimmer]

As someone pointed out here someplace....this is ridiculous on a car this expensive. M brakes or not, a car squealing this badly is unacceptable. What is it an old city bus? Absolutely shameful how many folks report this horrible noise. I have the carbon brakes so get no squeal. But if I didn't this would grind me big time. BMW should be ashamed that their cars do this at all. FIX IT BMW. If they couldn't I'd leave the brand with a giant finger to them on my way out.

[m3_08]

I don't know why but my brakes dont make any noise. May be I don't use them enough? 3K miles and no complains

[claykin]

Originally Posted by m3_08

I don't know why but my brakes dont make any noise. May be I don't use them enough? 3K miles and no complains

Sounds like a factory defect.

[M8CompSoCal]

Carbon ceramics and I have some light noise couple hundred miles in thus far.

[Accentu8]

Dropped car off this morning. Played the video for the SA. He agreed that the noise is excessive and should not be happening. Said they will chamfer the pads so that dust doesn’t collect between pad and rotor and stay there. Luckily, it also squealed when they were pulling it out of the receiving area. I will update once I get the car back.

[claykin]

Originally Posted by 23TripleBlack

Dropped car off this morning. Played the video for the SA. He agreed that the noise is excessive and should not be happening. Said they will chamfer the pads so that dust doesn’t collect between pad and rotor and stay there. Luckily, it also squealed when they were pulling it out of the receiving area. I will update once I get the car back.

Chamfering should help the issue, and I suspect the tech will also sand the face of the pads. In my experience with previous BMWs and MSport brakes, this is usually a temporary fix. Hopefully you have better luck.

BMW really needs to redesign their MSport brake pads. The dusting alone is a good enough reason. This has been an issue for nearly 10 years now.

[Accentu8]

Got car back today…finally. Still squealing. Not as bad and really only in high traffic situations where more aggressive driving/braking is not possible. Will give it the weekend and see. I have PPF Tuesday and tires Wednesday so will be late next week anyway before I can take it back in. I’m probably going to ask about different pads. Does anyone know if BMW service will install a non-BMW pad if I purchase and take the pads to them? If not, I worry that BMW could try to void my warranty on other things with brake system. I’ve never had an issue with brakes before.

[M8Bimmer]

Originally Posted by 23TripleBlack

Got car back today…finally. Still squealing. Not as bad and really only in high traffic situations where more aggressive driving/braking is not possible. Will give it the weekend and see. I have PPF Tuesday and tires Wednesday so will be late next week anyway before I can take it back in. I’m probably going to ask about different pads. Does anyone know if BMW service will install a non-BMW pad if I purchase and take the pads to them? If not, I worry that BMW could try to void my warranty on other things with brake system. I’ve never had an issue with brakes before.

That would be a real kick in the ass. BMW made them to squeal and then voids your warranty when you try to fix it.
Outrageous they make any noise. I have had cars worth a tenth of what we pay for these cars that made zero brake noise ever. And they stopped fine as well.

[claykin]

Originally Posted by 23TripleBlack

Got car back today…finally. Still squealing. Not as bad and really only in high traffic situations where more aggressive driving/braking is not possible. Will give it the weekend and see. I have PPF Tuesday and tires Wednesday so will be late next week anyway before I can take it back in. I’m probably going to ask about different pads. Does anyone know if BMW service will install a non-BMW pad if I purchase and take the pads to them? If not, I worry that BMW could try to void my warranty on other things with brake system. I’ve never had an issue with brakes before.

Give it a few weeks to see if the squeal settles down to a more acceptable occasional squeak. My 5 series did and I'm hoping this 8 series does too (I'm already noticing an improvement with 3000 miles on the clock). I try to avoid wrenches on my car whenever possible, even though my dealer has a tech that has been awesome and he is the only one who works on my cars.
I suggest giving it 2000-3000 miles or so. If the squeal persists then ask your dealer to setup an appointment with the after sales rep who comes around to dealers every couple of weeks. He's the official BMWNA employee who can better guide you and possibly ok the dealer to install third party pads (they likely won't approve it, but worth a try). The rep might offer another "fix".

[RJC-1]

MB had this issue years ago and it was due to iron rotors that were made slightly out of spec which caused a squeal. It took MB quite a while to get it sorted out and my shop foreman showed me there were actually two part #'s for the same rotors with the second # being the updated version, and once installed after 2 previous attempts with the old part #, the squeal was finally cured for good.

It's possible due to supply issues BMW may have contracted with a new rotor supplier and they are a bit out of spec, when this occurs it sets up a very slight vibration between the pad and rotor, and hence the squeal.

Ceramics are another story altogether.

[Accentu8]

Originally Posted by RJC-1

MB had this issue years ago and it was due to iron rotors that were made slightly out of spec which caused a squeal. It took MB quite a while to get it sorted out and my shop foreman showed me there were actually two part #'s for the same rotors with the second # being the updated version, and once installed after 2 previous attempts with the old part #, the squeal was finally cured for good.

It's possible due to supply issues BMW may have contracted with a new rotor supplier and they are a bit out of spec, when this occurs it sets up a very slight vibration between the pad and rotor, and hence the squeal.

Ceramics are another story altogether.

Good info, thanks! I wondered if it could be rotors since I heard that a warped rotor can cause a high pitched loud squeal, which is what I have.

Although I drove it again a little while ago and it is better, not as loud or as often so hoping that trend continues or improves even more.

I really enjoy just driving, no destination in mind and something being “wrong” with my brand new car, sucking a lot of the enjoyment out of the experience.

[RJC-1]

Originally Posted by 23TripleBlack

Good info, thanks! I wondered if it could be rotors since I heard that a warped rotor can cause a high pitched loud squeal, which is what I have.

Although I drove it again a little while ago and it is better, not as loud or as often so hoping that trend continues or improves even more.

I really enjoy just driving, no destination in mind and something being “wrong” with my brand new car, sucking a lot of the enjoyment out of the experience.

If you're not getting a vibration in the steering wheel at higher speeds when braking, the rotors are not warped, but they just need to be out of spec a bit to create a squeal.

[claykin]

Originally Posted by RJC-1

MB had this issue years ago and it was due to iron rotors that were made slightly out of spec which caused a squeal. It took MB quite a while to get it sorted out and my shop foreman showed me there were actually two part #'s for the same rotors with the second # being the updated version, and once installed after 2 previous attempts with the old part #, the squeal was finally cured for good.

It's possible due to supply issues BMW may have contracted with a new rotor supplier and they are a bit out of spec, when this occurs it sets up a very slight vibration between the pad and rotor, and hence the squeal.

Ceramics are another story altogether.

Anything is possible. BMW likely has an Alternative Vendor List for many parts in these cars. It's far too risky to rely on single sourcing for components more easily available through various vendors. Brake rotors, pads, caliper, wear sensor, expansion spring, paste, etc... A lot of possibilities.

[RJC-1]

Originally Posted by claykin

Anything is possible. BMW likely has an Alternative Vendor List for many parts in these cars. It's far too risky to rely on single sourcing for components more easily available through various vendors. Brake rotors, pads, caliper, wear sensor, expansion spring, paste, etc... A lot of possibilities.

With todays supply constraints it makes it much more likely there are parts not fully up to spec. I personally know of a few marques that have faced issues because of it with some being major and strictly due to new suppliers.

[claykin]

Originally Posted by RJC-1

With todays supply constraints it makes it much more likely there are parts not fully up to spec. I personally know of a few marques that have faced issues because of it with some being major and strictly due to new suppliers.

Sure. In most cases suppliers eat the cost of defective parts that fail to meet the approved engineering design. Risky for suppliers to not sample check from each production lot.

[Accentu8]

Update. I had a survey after my service where I explained my issues and the steps that the dealer took to resolve that didn’t resolve. I received a call from the dealer today offering to speak to BMW and propose full brake system replacement and provide me a comparable loaner during this time. He did caution that it’s not a slam dunk to get BMW to agree to full brake system replacement. If they can’t get that done or can’t get it fixed another way, they floated idea of buying the car back and ordering me a new one. I’ll update as I get more info.

[claykin]

Originally Posted by 23TripleBlack

Update. I had a survey after my service where I explained my issues and the steps that the dealer took to resolve that didn’t resolve. I received a call from the dealer today offering to speak to BMW and propose full brake system replacement and provide me a comparable loaner during this time. He did caution that it’s not a slam dunk to get BMW to agree to full brake system replacement. If they can’t get that done or can’t get it fixed another way, they floated idea of buying the car back and ordering me a new one. I’ll update as I get more info.

I'd tread lightly on allowing them to tear your car apart. More than likely the squeal will reduce over time to what most other owners experience. Or you can let them have another go at it at your first oil service.

I've been through what BMW calls "trade assist". I highly doubt they'd approve it in this case and not without more work being done to address the problem. That said see my note above. I do suggest you give it a few weeks. Since I started this thread I've already noticed a reduction in squeal from my 840GC.

[Accentu8]

I appreciate your feedback, I really do, but a reduction of squeal is not what I’m after. I want no squeal at all. There is no reason for brakes to make any noise and plenty of people have M brakes that don’t squeal.

Just going off of my experience on different cars with these brakes, I’d say it’s about 1 in 5 that squeal. Believe me, none of this is my preference, I absolutely love this car, but I can’t live with it, like it is now. I also believe that accepting the squeal is why BMW hasn’t fixed this.

Also, sorry if I’m repeating myself, but our 2021 Mustang GT with Brembos doesn’t make any noise whatsoever, regardless of weather and the Audi SQ5 I traded also had high performance brakes. Again, no noise at all.