[resbmw443]

Hi everyone,

I have a BMW G30 and recently started noticing a humming noise when coasting on the highway — specifically when I lift off the gas and the RPMs drop to idle (around 0 load).

The noise disappears when I’m accelerating or braking, and is only noticeable when coasting. I brought it to my service shop, and they told me it might be caused by an overtightened seal in the rear differential.

Has anyone experienced something similar or heard of this being the cause? I’m trying to figure out if this diagnosis makes sense or if I should investigate other possible issues.

Thanks for any input or advice!

[Nerdking]

Hey did you find anything on this? What model do you have? Is it rwd or xDrive? My 2021 530i RWD with 59k miles just started doing this.

[resbmw443]

No, basically they told me I should just monitor the noise for now. If it starts getting louder, then they’d need to rebuild the rear differential. But honestly, I’m not convinced that’s the actual issue. It’s a RWD 520d, so I’m wondering if it could be something else causing the noise.