Brake Squeal - Where does it emanate from?

[Sleepr72]

Hi All,

I have excessive brake squeal in my 2016 F85 X5M with 40K KMs (25K miles). I've replaced the discs/rotors and pads (EBC Yellow Stuff) with correct bed-in procedure and the brake squeal is getting worse.

I've spent many hours researching the causes and solutions, of which there seem to be many aftermarket solutions that claim to eliminate the squeal.

What I can't find is a definitive answer on, where does the squeal emanate from?

My many years of mechanical knowledge suggests there is two possible/logical areas;

A: Vibration between the disc/rotor and the friction material of the brake pad.

B: Vibration between the brake pad backing plate and the caliper piston(s).

There is aftermarket solutions for both possibilities;

For A: BG Stop Squeal. Applied to the friction material of the brake pad and allowed to penetrate it thoroughly before reinstalling brake pads.

https://www.bgprod.com/catalog/brakes/bg-stop-squeal/

For B: CRC Disc Brake Quiet. Applied to the brake pad backing plate and allowed to get tacky before reinstalling brake pads.

https://www.crcindustries.com/produc...t-4-fl-oz.html

There are many more solutions for possibility B from reputable manufacturers such as Brembo, Bendix, DynaGrip, Permatex, Würth etc.

Interested on everyone's thoughts, knowledge and experiences in this area.

Cheers,
Chris.

[MBoss_F86]

Brake squeal happens because of the material used in OEM brake pads. Powerstop pads and OEM Rotors are best combo for squeal free and low dust solution. I replaced oem pads with powerstops few months ago and no squeal whatsoever. Remember initial bite is about 90% compared to oems. I am very happy with them


Power Stop Z23-919B Rear $54.00 https://www.amazon.com/dp/B00O6PVEHS

Power Stop Z23-1738 Front $116.00 https://www.amazon.com/dp/B086M7J4DV

Hella Pagid 355251731 (2) $13.00 https://www.amazon.com/dp/B01IP984EG

[m3fuz]

Originally Posted by MBoss_F86

Brake squeal happens because of the material used in OEM brake pads. Powerstop pads and OEM Rotors are best combo for squeal free and low dust solution. I replaced oem pads with powerstops few months ago and no squeal whatsoever. Remember initial bite is about 90% compared to oems. I am very happy with them


Power Stop Z23-919B Rear $54.00 https://www.amazon.com/dp/B00O6PVEHS

Power Stop Z23-1738 Front $116.00 https://www.amazon.com/dp/B086M7J4DV

Hella Pagid 355251731 (2) $13.00 https://www.amazon.com/dp/B01IP984EG

Yep - I used the Power Stops above and the squealing went away. I can't believe BMW sent a car to production with this issue.

[MBoss_F86]

Originally Posted by m3fuz

Yep - I used the Power Stops above and the squealing went away. I can't believe BMW sent a car to production with this issue.

Not just BMW. mercedes, audi ans porsche have this squeal issue with their high performance pads

[Chilled]

I dono, have haven't seen many AMGs, RS or Porsches squeal like ours, it gets so bad like metal on metal.

And its not like our brakes are that good.

The squeal is due to compound, and the dust that is on the rotors. If you do a couple of hard stops, it goes away. But then you are wearing away more of your rotors/ pad.

[zebka2019]

Originally Posted by Chilled

I dono, have haven't seen many AMGs, RS or Porsches squeal like ours, it gets so bad like metal on metal.

And its not like our brakes are that good.

The squeal is due to compound, and the dust that is on the rotors. If you do a couple of hard stops, it goes away. But then you are wearing away more of your rotors/ pad.

That's right. The squeal is due to road and brand contaminants sitting on brake pads and rotors. Like you mentioned when you apply brand a little harder it goes away or also what I noticed is that when I use iron remover on wheels and brakes during car wash, squeal goes away for almost a day

[m3fuz]

Originally Posted by MBoss_F86

Not just BMW. mercedes, audi ans porsche have this squeal issue with their high performance pads

I don’t think my BIL’s GLE63 and my neighbor’s RS6 Avant squeal like the F85.

[Chilled]

Exactly Mercedes, Audi, Porsche all managed to figure out how to stop thier cars without massive squeal.

I know people are running powerstop and are happy with 90% of the OEM initial bite, i'm not. I would gladly pay OEM pricing for the pads, if they give the same stopping power, just minus the squeal.

And that BG stuff is not the answer, as another member has managed to wash it off whilst washing the car.

[Crunkzilla]

Originally Posted by MBoss_F86

Brake squeal happens because of the material used in OEM brake pads. Powerstop pads and OEM Rotors are best combo for squeal free and low dust solution. I replaced oem pads with powerstops few months ago and no squeal whatsoever. Remember initial bite is about 90% compared to oems. I am very happy with them


Power Stop Z23-919B Rear $54.00 https://www.amazon.com/dp/B00O6PVEHS

Power Stop Z23-1738 Front $116.00 https://www.amazon.com/dp/B086M7J4DV

Hella Pagid 355251731 (2) $13.00 https://www.amazon.com/dp/B01IP984EG

thank you.

[mrjsmith88]

We should have some sort of lawsuit against BMW for this problem… car is a lot of money to be driving around sounding like a bus when stopping.

[slow_roll]

Kinda look at this matter as par for the course. I rarely if ever stick with OEM pads for any vehicle. Aftermarket tends to have superior alternatives at a reasonable cost. Speaking of brake squeal, Porsche's PCCB on my GT4 hurts the ears when they get some use and brake dust accumulation.

[E21-myfirstlove]

Sometimes I press the brake pedal for about 3 seconds while maintaining throttle input. To "clean" the surfaces. Not a perm solution though. Not hard, just to engage. Someone lmk if this is anreally bad thing to do. Kinda like left foot braking on the track.

[Housekeeping]

My ‘19 911 squels more than my f85

[sly1types]

Originally Posted by MBoss_F86

Brake squeal happens because of the material used in OEM brake pads. Powerstop pads and OEM Rotors are best combo for squeal free and low dust solution. I replaced oem pads with powerstops few months ago and no squeal whatsoever. Remember initial bite is about 90% compared to oems. I am very happy with them


Power Stop Z23-919B Rear $54.00 https://www.amazon.com/dp/B00O6PVEHS

Power Stop Z23-1738 Front $116.00 https://www.amazon.com/dp/B086M7J4DV

Hella Pagid 355251731 (2) $13.00 https://www.amazon.com/dp/B01IP984EG

Hey, do these pads cover/sweep the whole rotor face? I know like 4 years ago when i looked for pads a lot companies just sold M5 pads for the X5M, but they would leave a rust ring.

Are you still liking them?

Thanks Kevin

[Yuille36]

I can verify that compared to my F85 X5M, my W211 E63 AMG never squealed as loudly as the X5M. Although my AMG did squeal and very low speed 1-2 mph when lightly applying the brakes, but the X5M squealed like a stuck pig.
Ever since I found carbon ceramic pads for the AMG, I have never looked back. Now I run them on all my vehicles including the F80 M3. Now that are many companies that manufacture these types of brake pads. And I couldn't tell you which is the best. But the Z26 pads from Power Stop work so well, that I would change them. Anytime, I purchase a vehicle one of the first thing I purchase is new pads and rotors for the future. So, I purchased Akebono carbon ceramics for the M3, for my next pad change, but that will not happen for a few years.
And one the greatest things about carbon ceramics, are that there rotor friendly, meaning they don't wear out the rotor like semi metallic pads do.

[tfunk88]

Originally Posted by sly1types

Hey, do these pads cover/sweep the whole rotor face? I know like 4 years ago when i looked for pads a lot companies just sold M5 pads for the X5M, but they would leave a rust ring.

Are you still liking them?

Thanks Kevin

Yes, they sweep the whole rotor face…and both the squealing AND crazy dusting is gone for me