[Travelfreek]

Hey fellow beemers
I have a 2015 F10 550i with about 42k miles. This is now the start of the second winter I have owned this car and as the outside temp drops below 35-40F, when I start the car and begin to drive I hear an occasional whine, like a power steering pump whine. It most often happens as I accelerate from a stop and happens in lower RPM's only about 1000-1500 and does not last very long. The sound only happens as I accelerate and never happens at an idle.
Last winter while vehicle was under warranty I had the dealer look at it and they could not find anything - no surprise.

Anybody have a similar issue or resolved such an issue?

[CLT550F10]

I have 16 550 and have something similar, although I think it's coming from the rear/transmission. Haven't diagnosed it yet either and didn't realize it started as the weather started getting colder.

Subscribing to the thread as I'm curious if others know what this is...

[EL Jeffe 5]

pulley bearing maybe

[Travelfreek]

Originally Posted by EL Jeffe 5

pulley bearing maybe

El Jeffe 5,
I will have to check that - did not think of that but you might be on to something as it does sound slightly like a bearing in vibration or cavitation.

[EL Jeffe 5]

if in fact this turns out to be Bearing I wouldn't buy whole pulley because you can get bearing on internet for next to nothing vs buying new pulley.
if you have Vise and couple sockets this can be done in 15 min Good luck

[Travelfreek]

Originally Posted by EL Jeffe 5

if in fact this turns out to be Bearing I wouldn't buy whole pulley because you can get bearing on internet for next to nothing vs buying new pulley.
if you have Vise and couple sockets this can be done in 15 min Good luck

That was my plan EL Jeffe - Thanks I will be working on it this weekend and will let you know the result when I figure it out.

[535_BiTurbo]

turbo bearing or pressure converter failing?? any codes?

[CLT550F10]

OP, any update on what you were able to find?

[Travelfreek]

no codes and yesterday I changed the deflection pulley and belt tensioner - fingers crossed that fixes it.

[CLT550F10]

Originally Posted by Travelfreek

no codes and yesterday I changed the deflection pulley and belt tensioner - fingers crossed that fixes it.

Good luck, keep us posted...

[BurrNinja]

Does it happen when the car is warm?
Edit: nvm reread title haha
Any trans pan leaks? If only hearing at 1000 to 1500 rpm wonder if it's low on fluid or just not up to temp.

[Travelfreek]

Sadly no change to the noise now that I changed the deflection pulley and belt tensioner - noise is definitely engine related and the summer months never makes a sound.

[Travelfreek]

BurrNinja - no trans or fluid leaks that I have had since I have owned the vehicle, in fact while changing the pulleys I had all three bottom covers off and the only leaks I noticed was a small engine oil leak around the oil filter. I now have 44K miles and at 50K miles I will change the trans fluid and filter/pan. Maybe it is a bit low somehow, but why only noise when the the temps outside are cold and only until car reaches operating temps?

[BurrNinja]

Usually lower fluid will make transmission work harder to pump fluid causing the whine until it warms up. Can be the filter clogged possible also. Thats only explanation I can think of as far as whining at rpms.

[Travelfreek]

UPDATE - I SEEM TO HAVE FIXED IT!!!

So over the weekend I serviced my transmission - you know the transmission BMW states has lifetime fluid...
I have 47K miles on my 2015 550i.

Now since I am in Chicago area my car sat in heated garage all weekend and did not get to test or run much after the trans service. However, this morning with outside temps of 1 degree F, and after car sat out all night, the car started and drove away with NO MORE WHINNING NOISE!!!

So the conclusion - must have been a bit low on fluid I am guessing or more likely filter was clogged and causing pump scavenging. I drained off about 5-6 liters, replaced pan with filter and refilled per OE refill process/instructions with 5.5 liters....

See picture of drained fluid versus new fluid. Props to ECS Tuning for supplying the trans service kit.
I will be changing fluid and filter every 40K going forward!

[Travelfreek]

UPDATE::
10 days later and about 150 miles and whining noise is all gone - definitely related to transmission and servicing the trans solved the issue.