Common noise? Transmission whine

[farbarg]

Folks,

For s@#! and giggles, I thought, what the heck? Let's start another noise thread.

When my car is "cold", say under 150F, I get a distinct whine from the transmission at apprx. 2.1K RPM's. When completely cold, this whine is quite loud from the outside. As heat builds in the transmission (my hypothesis) the noise diminishes (though, if you listen carefully, it is still there). Clearly there is some structural resonance at that RPM, thus it reminds me of the 5th gear 2K RPM engine resonance that BMW has already made statements about. However, this seems to be only the transmission.

And I've done some searches, but I haven't seen a thread dedicated to this. And to be clear, this is not the transmission clunk, the flywheel clatter/tupperware sound, the never diagnosed tin-can clank, or the LSD rubbing noise. That is a pretty awesome list, though.

Anyone else?

[JCtx]

How about stating DCT or 6MT for starters?

[farbarg]

Originally Posted by elp_jc

How about stating DCT or 6MT for starters?

Sure, 2008 E90 MT.

[JCtx]

Is it something that wasn't there before, or that you just noticed? I've never heard my car from the outside because I always drive it , so can't help you there. But these trannies are noisy man, and balky with load reversals. If it's only making weird noises when cold, I wouldn't worry about it. It's also notchier, and 1st hard to engagen while moving (even at crawling speeds) when cold, so probably a normal trait. I don't know if all gears are helical-cut, or if first is straight-cut, which could explain the whine since they're inherently noisier.

You should shoot a short vid INSIDE the car, and many of us would tell you if it sounds normal. If you can't hear the noise from the inside with windows down, I wouldn't worry about it. And it could be your differential too; hard to tell from a distance. Keep us posted.

[JOHNBMWM5]

Never herd this, M3 2010 with M-DCT and 5K miles.

[farbarg]

Originally Posted by elp_jc

Is it something that wasn't there before, or that you just noticed? I've never heard my car from the outside because I always drive it , so can't help you there. But these trannies are noisy man, and balky with load reversals. If it's only making weird noises when cold, I wouldn't worry about it. It's also notchier, and 1st hard to engagen while moving (even at crawling speeds) when cold, so probably a normal trait. I don't know if all gears are helical-cut, or if first is straight-cut, which could explain the whine since they're inherently noisier.

You should shoot a short vid INSIDE the car, and many of us would tell you if it sounds normal. If you can't hear the noise from the inside with windows down, I wouldn't worry about it. And it could be your differential too; hard to tell from a distance. Keep us posted.

Thanks for the feedback. That's a great idea; I'll try to get some time to do this this coming weekend.

[raiste]

Has it always done this? All gears, or just certain ones? How many miles on the car?


.

[farbarg]

Originally Posted by raiste

Has it always done this? All gears, or just certain ones? How many miles on the car?


.

23k miles. Gear doesn't matter, only RPM. I've noticed it for at least the last 5k miles, but seems to be slightly worse now.

[Chako]

50k km on the car, 6MT.

I get a whine around 2-3k RPM @ 10-50% throttle. Sounds like it's from the diff?
I usually notice it in 4th, 5th, & 6th. Doesn't matter if the car is cold or warm.

What could be going on?

Thanks!

[1sikbmr]

Originally Posted by Chako

50k km on the car, 6MT.

I get a whine around 2-3k RPM @ 10-50% throttle. Sounds like it's from the diff?
I usually notice it in 4th, 5th, & 6th. Doesn't matter if the car is cold or warm.

What could be going on?

Thanks!

this whine is normal... My car does this too. It is a slight whine and when you tap the gas you hear it but with more gas applied it goes away...

[xfactor]

Sorry to bring back an old thread. But does anyone has an idea where it's coming from or how to get rid of it?

[mmm def]

Originally Posted by xfactor

Sorry to bring back an old thread. But does anyone has an idea where it's coming from or how to get rid of it?

It's from the diff, it's normal, you don't get rid of it.

[xfactor]

Originally Posted by mmm def

It's from the diff, it's normal, you don't get rid of it.

Took it into the local dealer today. The techs take it for drive and couldn't figure out where the noise is coming from. Take a for a second road test and after the fact they put it up on the hoist and pin point it to the fact that it's the differential.

Tells me that I need to change the differential to get rid of the noise. Mine is out of warranty by 5xxx miles. Don't think I want to pay 5K (parts and labour) to fix this now. Plus I want to get a second opinion on what the noise is and why it is happening. Annoying!

[RBB]

Originally Posted by Chako

50k km on the car, 6MT.

I get a whine around 2-3k RPM @ 10-50% throttle. Sounds like it's from the diff?
I usually notice it in 4th, 5th, & 6th. Doesn't matter if the car is cold or warm.

What could be going on?

Thanks!

I don't like to resurrect old threads, but I'm having this exact same issue with an 08 M3, 6MT, 46K miles. I've never noticed it before, but it's been going on for about a week now. A very faint whine (almost sounds like a whistle) around 2-2.5K RPM @ low throttle levels in 4th, 5th and 6th.

What's the consensus around here, normal? If the car had been doing this from day 1 I wouldn't worry about it, but this is a new thing. I'm changing the diff fluid this weekend as a precaution and it's about that time anyways.

[IM Buddy8]

Mine only does this if it's super cold out and for the first mile or so. Anyone else experience this and is it normal/not doing any harm?

Originally Posted by RBB

I don't like to resurrect old threads, but I'm having this exact same issue with an 08 M3, 6MT, 46K miles. I've never noticed it before, but it's been going on for about a week now. A very faint whine (almost sounds like a whistle) around 2-2.5K RPM @ low throttle levels in 4th, 5th and 6th.

What's the consensus around here, normal? If the car had been doing this from day 1 I wouldn't worry about it, but this is a new thing. I'm changing the diff fluid this weekend as a precaution and it's about that time anyways.

[quiksi]

Mine’s been doing it for a few months but it goes away as soon as the car is warm. I plan to change the transmission and differential fluids early and send in for UOA.

[Helmsman]

Originally Posted by quiksi

Mine’s been doing it for a few months but it goes away as soon as the car is warm. I plan to change the transmission and differential fluids early and send in for UOA.

Mine had a faibt whine around 2.5k rpm (cold/warm) which went away with new diff fluid. Fluid coming out looked and smelled just fine so the change in noise was surprising.

[its55]

I might be having this same noise, not sure. I have an '08 DCT. It's been cold out, for one thing. I would describe the noise not so much as a whine, but a lower pitched hum. It does rise and fall with shifts. Seem like the same thing?