[kamek]

Anyone experiencing squeaking/squealing brakes with their M40i? I have under 5k miles on my car and my brakes have been squeaking with light pressure at low speeds/when nearing a full stop. It has become quite annoying and not something I was expecting to deal with so early on. Thanks in advance for any insights.

[Neo1130]

Usually squeaking brakes are from not properly bedding them in or too harsh of braking too frequently. This creates a smooth or "glazed" surface which is what causes the noise. Rough brake surfaces don't cause noise... Smooth ones do.

What you need to do now is do a few runs from about 50 down to 10 mph, enough to get your brakes HOT... You'll either experience brake fade or smell them... Once that happens, drive about 20 miles with minimal braking to cool them off... And while hot, DO NOT by an means come to a complete stop. This will cause your rotors to cool unevenly causing warping.

[Scottatah]

Also feel like i've had that from right early on. 11,000km here. Full intentions of complaining when i go for my first service but not really expecting a ton. Plus we're getting into winter now so less window down driving which means I don't hear it and get less frustrated.

[jjrandorin]

Originally Posted by Neo1130

Usually squeaking brakes are from not properly bedding them in or too harsh of braking too frequently. This creates a smooth or "glazed" surface which is what causes the noise. Rough brake surfaces don't cause noise... Smooth ones do.

What you need to do now is do a few runs from about 50 down to 10 mph, enough to get your brakes HOT... You'll either experience brake fade or smell them... Once that happens, drive about 20 miles with minimal braking to cool them off... And while hot, DO NOT by an means come to a complete stop. This will cause your rotors to cool unevenly causing warping.

I dont have my (wifes) X3 m40 yet, but I DO have a 435 with M sport brakes and this is spot on. These sport brakes expect to be... well... braked sportly (lmao). Usually these are driven around town like the regular cars they are.

In my 435 (again with M sport brakes), they start to squeak in the mornings after a few months, and I perform the process laid out here, which solves the issue... temporarily for a few weeks / months till I need to do it again.

In general, I dont brake agressively, and since these are brakes that are designed to do that, with pads that are designed for that as well, I figure that is just a part of having the (very nice) M sport brakes.

[PerthBMW]

You could always spray a bit of WD40 on them....

[DanTosi]

I have had the same problem and have LESS that 1500km on them. They have been making noise since day 1. Very annoying, planning to call the dealer soon

[jjrandorin]

Originally Posted by DanTosi

I have had the same problem and have LESS that 1500km on them. They have been making noise since day 1. Very annoying, planning to call the dealer soon

See neo1130's post for brake "bedding in" process. In my opinion, since the M sport brakes have more braking power, they need a bit more care in doing things like bedding them in, that is not necessary on BMWs with the regular braking setup.

[kamek]

Originally Posted by Neo1130

Usually squeaking brakes are from not properly bedding them in or too harsh of braking too frequently. This creates a smooth or "glazed" surface which is what causes the noise. Rough brake surfaces don't cause noise... Smooth ones do.

What you need to do now is do a few runs from about 50 down to 10 mph, enough to get your brakes HOT... You'll either experience brake fade or smell them... Once that happens, drive about 20 miles with minimal braking to cool them off... And while hot, DO NOT by an means come to a complete stop. This will cause your rotors to cool unevenly causing warping.

Thanks Neo! It was probably caused by all my city driving. I need to figure out where I can even find a 20 mi stretch in NYC.

[Neo1130]

Originally Posted by kamek

Thanks Neo! It was probably caused by all my city driving. I need to figure out where I can even find a 20 mi stretch in NYC.

Probably in all honesty won't need the 20 miles... I've just gone about 5 to 10 before and haven't had any issues on a few different vehicles but I wouldn't want to chance any rotor warping if at all possible.

[kamek]

Originally Posted by Neo1130

Probably in all honesty won't need the 20 miles... I've just gone about 5 to 10 before and haven't had any issues on a few different vehicles but I wouldn't want to chance any rotor warping if at all possible.

I'll take the 20 mile suggestion. It gives me more of a reason to drive my car