[Crusader]

Wife's 2019 330i with standard brakes replaced with similar 2023 car only it has the M-Perf brake option. Brakes are hyper sensitive, grabby, and have a lot of unusual noises coming from the rear (clunks, sometimes howls when stopping in reverse). I haven't dealt with BMW dealer tech yet, but wife has been blown off when she's brought it in for service and complained about the brakes. "They're fine." I don't think so. I've owned eight bimmers and these are the worst brakes I've ever experienced. My E92 has excellent (non-M) brakes, progressive, easy to modulate, quite powerful. Has anyone else experienced lousy performance from the "upgrade" M-Perf brakes?

[HeatJoey]

Curious to hear others chime in on this as well. I dont have the m perf. Brakes on my sons m340 and I don’t belive my m40 has them either, although not 100% sure about that.

[BLK.G20]

They have been fine for me. BMW has a range of of sounds which they consider "normal" for brakes. Especially the new ones which no longer contain copper, a softer metal which reduced brake noise on previous model years. Clunking is probably caused by something lodged either in the wheel, rotor or stuck in the caliper. Worth taking in if you feel it is abnormal.

[Two3Series858]

Did the swap almost 6 months ago. Definitely can tell a difference. Occasionally the front brakes will squeak sometimes which IS kind of annoying since they've been worn-in but its weird how it'll happen one day and then I won't hear it again for 3 weeks. I will be looking into brake pad options when its due since the stock are pretty dusty.

[Dan B]

Originally Posted by Two3Series858

Did the swap almost 6 months ago. Definitely can tell a difference. Occasionally the front brakes will squeak sometimes which IS kind of annoying since they've been worn-in but its weird how it'll happen one day and then I won't hear it again for 3 weeks. I will be looking into brake pad options when its due since the stock are pretty dusty.

I get a random, I will call it a howl as it is not like a wear indicator squeak, at random times.

It started at about 6K miles and there is no obvious pattern. Both warm/cold, wet/dry, and after long or short drives.

I chalk it up to chaos theory.

[Two3Series858]

Originally Posted by Dan B

I get a random, I will call it a howl as it is not like a wear indicator squeak, at random times.

It started at about 6K miles and there is no obvious pattern. Both warm/cold, wet/dry, and after long or short drives.

I chalk it up to chaos theory.

Somebody mentioned that u will hear the rotors buffering (like fan blades) if ur driving around 20-40 mph and the windows down. I do hear THAT sometimes. I was told its due to air passing through the slotted and drilled portions of them. Maybe.

[Dan B]

Originally Posted by Two3Series858

Somebody mentioned that u will hear the rotors buffering (like fan blades) if ur driving around 20-40 mph and the windows down. I do hear THAT sometimes. I was told its due to air passing through the slotted and drilled portions of them. Maybe.

That is interesting. I have not had any buffering with any car I have driven with drilled rotors. But aero will obviously have a big impact and be unique to each car.

This is a howl under braking. Personally it does not bother me at all. I consider it part of the package with more aggressive brakes.

[rostrata]

I swapped to MP brakes last year. Yes, you will hear shit sometimes. Well, things I believe most people don't see as normal. I've learned all the noises and some of them are rare. Like backing out of the drive at slow speed after a rainy night... rust! So yes, it'll "howl" a bit, so to speak. Get going and it's gone. The clicking/fan blade noises are constant. I'm curious if many have the stupidly sensitive ears I have for these kinds of thigns but I will tell you they make noise at ALL speeds. You just probably have the windows up, not near a partition, or don't really pick up on noises like that. The reason is pricesily because they are DIMPLED and SLOTTED. Your previous cars with DRILLED rotors will have far less noise, if any that you might perceive. It's the dimpling and slotting that kills it. I've considered fully drilling my rotors to eliminate that clicking sound. But ECS said they have an MP brake rotor option (fully floated, like, actually floated, not riveted) under development. So I may wait to get those in hand before I do any science experiment for the community.

Otherwise, the MP brakes have indeed been a game changer. The M
Sport brakes that came stock did very well, indeed. But they couldn't handle the heat of a single canyon run. Pads and rotors galzed over. Took some time to get it back to near-normal operation, but without replacing the pads which were definitely smoked, that just wasn't going to happen. Took a chance on the MP brakes and while some say "they're the same!" they're dead wrong. They're close. But that extra inch of rotor surface and larger calipers and larger brake pads means better cooling. While they aren't crazy over the top, they are certainly worth it. Did the same canyon run a couple of months ago after I let them full break in and they performed exactly how I hoped they would. Except I replaced the front pads with Project Mu PS Type pads. Those are definitely better than the stock pads. No glazing. No heating issues. No fade. Just fun.

Also recommend Torque 700 brake fluid. Amazingly good modulation without over-biting but it'll have those pads clamping hard when asked.

[dimsum.dumdum]

The MP brakes on my 22' M340i are also grabby. Hated it at first but got used to it. I tracked the car last year. My car has the big brake / cooling option. I'm glad they are bigger because they honestly felt like they got spongy at the end of the 4th session. Upgraded to synthetic fluid and will be using race pads on my next outing. My advice is to learn to drive the car as advised. The MP brakes are built and biased for performance. They need to grip. It's the same on my wife's 22' X7-M50.