[MassNerd]

I need to get out and try some more things to better understand when exactly its happening, but the basic symptom is, after hard acceleration I noticed a whining sound from the transmission.

This morning, with DSC turned off and a little 0-40 run full throttle, the whine was quite noticeable. Just a single short run made the sound occur. Then after 2-3 minutes of cool down the sound goes away.

I want to test if this happens in comfort, sport and sport+ modes or if its related to DSC off (and the eDiff) only.

Thinking back to a year ago when I did a BMWCCA car control clinic, I flogged the car hard with DSC off for hours and it didn't make this whine at all.

I'm taking in the car for its 20K service Friday and will ask the dealer to look into it.

I was curious if anyone had experienced this and what it could be? Anything that could help point the dealership in the right direction.

[gosi]

It’s a common issue for the ZF8 transmission. Never heard of any failures because of it though.

[JD11937]

I haven't had this happen to me personally but have heard others speak about this sound. As the previous poster said, none of them have lead to any failure.

[MassNerd]

Thanks. This makes me feel better! I'll have to search for those posts.

[gosi]

Sorry to revive an old thread, but I have some news to share regarding my whining gearbox.

I replaced the original fluid with ZF LifeGuard Fluid 8 and I am happy to report that 2 months after the change I’m still not hearing any whine, whilst before during hard driving it was very obvious in second gear.

I’m posting this because it may be useful to other people with this issue. I haven’t heard of anyone who had the issue go away with just a fluid change. I’ve heard that manufacturers use low viscosity ATF for fuel economy reasons, so that may be why it whines during high load. It’ just a guess though... Anyway I hope someone finds this useful.