[Aronis]

Originally Posted by ThugzZ BunnY

I just delivered an m2 to a customer yesterday and when I drove it to the gas station I heard the whining noise when slowing down. I believe it has to be the diff cause it would still make the noise if I let off the brakes. Gonna talk with our head tech to see if he knows what it is.

You work for BMW? The diff fluid in the DCT is supposed to be changed at the 1200 mile service. The noise is a known expected issue with the brand new differential.

Mike

[David1]

DCT fluid does not get changed at the 1200 mile service. Just the diff.

[termigni]

Originally Posted by ried

This is the sound a new differential makes and is 100% normal. The whiney, jet engine winding down noise is present on every new M2/M3/M4. Mine did it just like everyone else's. Goes away after a few hundred miles.

Enjoy it while it lasts. I thought it was kind of neat!

Just picked up an '18 and I have this Whine when slowing down to stop. It's definitely coming from differential and I'm not worried. My old M3 used to make some crazy clunk sounds which was even worse but perfectly normal.

[MRufo]

Originally Posted by ried

This is the sound a new differential makes and is 100% normal. The whiney, jet engine winding down noise is present on every new M2/M3/M4. Mine did it just like everyone else's. Goes away after a few hundred miles.

Enjoy it while it lasts. I thought it was kind of neat!

Yep. It went away in my car too after a 100 mi or so.

[Spa2k]

Originally Posted by termigni

Just picked up an '18 and I have this Whine when slowing down to stop. It's definitely coming from differential and I'm not worried. My old M3 used to make some crazy clunk sounds which was even worse but perfectly normal.

Mine's doing the same thing. I'm calling it normal until it blows up.

[norMcal]

I would say, do a proper break bedding in procedure, then enjoy your vacation and drive the car around. If the noise goes away over time, great, if not, then you tell them to fix it when you drop the car off before they ship it to the US.

[JustChris]

Originally Posted by Prodigy.

Is it only when braking? Mine made a very noticable noise for the first few 100kms, i believe it is to do with the brakes bedding in, but it will go away if so.

If not it could be the diff, i also do get a less noticable whining nose when traveling at low speeds but i also get the mattalic clang associated with a dodgy diff.

Mine did this while braking

[Spa2k]

The whining is present in my M2 whether I'm braking in gear or coasting to a stop in or out of gear, so it's not the brakes. Actually, I think the whining may be coming from me, because BMW says I have to drive so conservatively for the first 1,200 miles.

[JustChris]

Insert 'is it coming from the passenger seat' jokes here...