[metrathon]

lol @bluemark81 you're still trying, aren't you

I don't think it's a mirror issue. My noise CLEARLY comes from the top of the B-pillar, and not from the A-pillar or windshield or anywhere else.
At the top of the B-pillar sounds like the door doesn't shut completely. It might be the window molding, the door is misaligned, or poor rubber sealing. The mirror has nothing to do with it.

[metrathon]

Originally Posted by bavarianboar

picked up an MY13 328i Luxury line and was not happy with the wind noise.

Was driving it with a relative while they took delivery of the car, and spent about 5-6 hours driving on the freeway.
Even at moderate speeds like 60mph, there is plenty of 'noticeable' wind noise which is totally absent in my E90.
Lots of swooshing sounds as if you are driving through heavy wind areas (speaking from E90 experience of 36k miles).

My 2014 335i Msport is on order, here is hoping things will be better there.

Welcome to the club. But realistically speaking, you shouldn't complain about the wind noise, for the $18,000 you pay for the car

[lightyear36]

Originally Posted by bluemark81

Ok, I've tried doing this to my mirror. I cut a couple of foam pieces to modify the shape of the mirror and to fill the gap that exists between the mirror housing and the side of the car. I then wrapped the entire mirror in saran wrap and then taped it so it would all stay in place. My goal was not really to quiet the wind noise, although, if it did, great. My goal was to see if it had any impact on the noise I am hearing near the b-pillar. It would appear as though this had absolutely no impact on the wind noise I am experiencing. I am now running out of things to try. One last thing I want to try is to build a brace that will span from the top of my drivers side window to the passengers side window to force each window out in hopes that it will form a better seal. I just haven't quite figured out how to build something so I can still get into the car and drive. I am considering using a telescopic painters pole or similar so I can adjust the force against the windows.

Hm, that sucks. Did at least the noise pattern change?

It is hard to believe that somebody doesn't have (or has a barely perceptible) swooshing noise at 200kph. I agree that stage 1 fixes (see above) do make a difference, but AFTER having applied them EVERYBODY should have stage 2 problem we are writing about. Ore are we talking about different F30 bodies here?

[bluemark81]

Originally Posted by metrathon

lol @bluemark81 you're still trying, aren't you

I don't think it's a mirror issue. My noise CLEARLY comes from the top of the B-pillar, and not from the A-pillar or windshield or anywhere else.
At the top of the B-pillar sounds like the door doesn't shut completely. It might be the window molding, the door is misaligned, or poor rubber sealing. The mirror has nothing to do with it.

I totally agree, but since so many are blaming the mirrors, I had to debunk the theory myself. Now I know it is not the mirrors causing it.

[bluemark81]

Originally Posted by lightyear36

Hm, that sucks. Did at least the noise pattern change?

It is hard to believe that somebody doesn't have (or has a barely perceptible) swooshing noise at 200kph. I agree that stage 1 fixes (see above) do make a difference, but AFTER having applied them EVERYBODY should have stage 2 problem we are writing about. Ore are we talking about different F30 bodies here?

I did not perceive any change in the noise pattern at all. To my 49 year old ears, there was absolutely no change.

[lightyear36]

Today I concentrated on the "B-pillar" part of the issue:





This time I added additional insulation in addition to taping. No changes at all :-(. Sorry, I'm done with the window seal theory unless somebody proves the opposite. Additionally, at higher speeds (110 mph) the wind noise seems to become ubiquitous coming from everywhere. If it were bleeding in through some hole, I think it would be MUCH more high-pitched and easily localisable. Next thing I will do is ask the dealer who sold me the car to let me test-drive his other F30s and perhaps an F10 for comparison.

Also, yesterday I've been to a dealer parking lot studying mirrors and driver's door insulation on different cars. What I've noticed was a different wind-breaker design of the mirror sockets.

This is how an F30 build January 2013 looks like:



This is how my build (June 2013) looks like:



I do NOT believe it makes much difference, just an interesting observation. X5 and E90 did not have any wind-breakers at all.

[bluemark81]

Originally Posted by lightyear36

Today I concentrated on the "B-pillar" part of the issue:





This time I added additional insulation in addition to taping. No changes at all :-(. Sorry, I'm done with the window seal theory unless somebody proves the opposite. Additionally, at higher speeds (110 mph) the wind noise seems to become ubiquitous coming from everywhere. If it were bleeding in through some hole, I think it would be MUCH more high-pitched and easily localisable. Next thing I will do is ask the dealer who sold me the car to let me test-drive his other F30s and perhaps an F10 for comparison.

Also, yesterday I've been to a dealer parking lot studying mirrors and driver's door insulation on different cars. What I've noticed was a different wind-breaker design of the mirror sockets.

This is how an F30 build January 2013 looks like:



This is how my build (June 2013) looks like:



I do NOT believe it makes much difference, just an interesting observation. X5 and E90 did not have any wind-breakers at all.

That is an interesting observation. Mine has the earlier design.

[bluemark81]

Originally Posted by lightyear36

2) Side mirror design. The ultimate test here would be WITHOUT the mirrors and WITHOUT the mirror sockets.

Do you still believe it to be the mirror design with your recent observations knowing you have the most recent mirror design and the mods I made with no perceived noise changes?

[lightyear36]

Originally Posted by bluemark81

Do you still believe it to be the mirror design with your recent observations knowing you have the most recent mirror design and the mods I made with no perceived noise changes?

I could tell you I do, or I don't, but without the test I mentioned we are speculating heavily. Got an appointment at the dealer on Monday to test-drive other F30.

[bluemark81]

Originally Posted by lightyear36

I could tell you I do, or I don't, but without the test I mentioned we are speculating heavily. Got an appointment at the dealer on Monday to test-drive other F30.

Well, I think I've confirmed, to myself anyway, that it is not the mirrors. I feel if it was the mirror design, I would have noticed at least a change in the wind pattern with my mirror modification. I will admit that it may have something to do with the wind flow across the glass since we've pretty much exhausted all other possibilities, but this could be caused by any number of things. We would have to start placing air diffractors at various locations to start nailing it down.

[BavarianFanatic]

It's very interesting that the mirror design has been tweaked. The extra spoilers serve no other purpose than to break up the air flow between the mirror body and the door.

Aerodynamics is a very complicated science. The mere fact that air is being forced between the two fixed surfaces (mirror and body) means that it's being compressed and accelerated. This alone will generate noise. Taping gaps and sealing joints won't make any difference. It's also important to understand that there's a multitude of different things that can cause noise and, because it's so subjective, different folks might be hearing different things but can easily relate to someone else and think their situation is similar/the same.

To test the mirror on an "old design" mirror, try attaching something that will have an effect similar to what you see in the photos. Even just some tape that you've rolled/folded onto itself to create a crease or ridge should make a difference.

[lightyear36]

Originally Posted by BavarianFanatic

It's very interesting that the mirror design has been tweaked. The extra spoilers serve no other purpose than to break up the air flow between the mirror body and the door.

Aerodynamics is a very complicated science. The mere fact that air is being forced between the two fixed surfaces (mirror and body) means that it's being compressed and accelerated. This alone will generate noise. Taping gaps and sealing joints won't make any difference. It's also important to understand that there's a multitude of different things that can cause noise and, because it's so subjective, different folks might be hearing different things but can easily relate to someone else and think their situation is similar/the same.

To test the mirror on an "old design" mirror, try attaching something that will have an effect similar to what you see in the photos. Even just some tape that you've rolled/folded onto itself to create a crease or ridge should make a difference.

I'm afraid you got it wrong. The one with LESS ridges is a NEWER design. And it doesn't seem to make any difference - the noise is way too massive to be influenced by a couple of minor dimples.

[Frogman]

Originally Posted by bluemark81

Well, I think I've confirmed, to myself anyway, that it is not the mirrors. I feel if it was the mirror design, I would have noticed at least a change in the wind pattern with my mirror modification. I will admit that it may have something to do with the wind flow across the glass since we've pretty much exhausted all other possibilities, but this could be caused by any number of things. We would have to start placing air diffractors at various locations to start nailing it down.

Another crazy idea: If you have a sunroof, have you tried taping the seal all the way around to see if air is getting in that way? I know it's a long-shot, but it may be worth a try...

[bluemark81]

Originally Posted by Frogman

Another crazy idea: If you have a sunroof, have you tried taping the seal all the way around to see if air is getting in that way? I know it's a long-shot, but it may be worth a try...

Lol, was thinking of trying that today. If I get arou d to it, I will let you know what I find out.

[lightyear36]

Originally Posted by Frogman

Another crazy idea: If you have a sunroof, have you tried taping the seal all the way around to see if air is getting in that way? I know it's a long-shot, but it may be worth a try...

If I had one, I would have taped it as well during my tests.

[bluemark81]

Originally Posted by Frogman

Another crazy idea: If you have a sunroof, have you tried taping the seal all the way around to see if air is getting in that way? I know it's a long-shot, but it may be worth a try...

Taping the sunroof makes no difference. Next?

[BavarianFanatic]

Originally Posted by lightyear36

I'm afraid you got it wrong. The one with LESS ridges is a NEWER design. And it doesn't seem to make any difference - the noise is way too massive to be influenced by a couple of minor dimples.

Actually, I don't. Those "little dimples" break up the laminar flow and create turbulence. This of course also increases drag.

[snowghost]

Originally Posted by BavarianFanatic

Actually, I don't. Those "little dimples" break up the laminar flow and create turbulence. This of course also increases drag.

Neurosis.

[bluemark81]

Originally Posted by BavarianFanatic

Actually, I don't. Those "little dimples" break up the laminar flow and create turbulence. This of course also increases drag.

Please think about what you just said and in the context of aerodynamics engineering and fluid dynamics. BMW does extensive wind tunnel testing and whilst most of us agree there is a noise issue, they would not purposely add dimples to induce turbulence where noise is a function of turbulence. These dimples as you call them are actually called longitudinal ridges. If these ridges generate turbulence and noise, in the mirror redesign, they would have removed them altogether rather than only removing one in the mirror redesign. I suggest reading up on trailing-edge noise theory.

"Trailing edge noise from a particular airfoil depends on the shape of the airfoil. Along with the external flow conditions, the airfoil shape determines the development of the turbulent boundary layers that interact with the trailing edge to produce noise. Details of the turbulent boundary layer, such as mean shear and velocity fluctuation distribution normal to the surface, are important factors in the efficiency of noise generation. These can be manipulated through passive airfoil shape changes that change the mean pressure gradient over the foil surface and thus influence evolution of the boundary layer."

Although, I would need to view the modelling results of BMW's wind tunnel testing, I highly doubt BMW added airfoil ridges to induce turbulence.

http://arc.aiaa.org/doi/abs/10.2514/6.2013-489

[lightyear36]

I've got some bad news. Just came back from the dealer who let me test-drive his demo F30 320d (6MT).

Short answer: seems like all F30s are noisy by design. People stating they have no wind noise at higher speeds most probably came from E90/E92, which was similarly noisy, therefore this is normal for them.

Long answer: the first thing I noticed was a stage 1 issue - an explicit high-pitched whistling from the right edge of the windshield (curable by the replacement of windshield side strips - has already been discussed here). This made me understand the difference between "stage 1 complaints" and "stage 2 complaints". Stage 1 is really bad, but fixable. Next, 320d is a much louder engine than 330d, therefore the wind noise is LESS noticeable (it is overlayed by the engine roar). Next, above 170kph the car had a very annoying low-freq droning/humming (rear differential broken?), which also wasn't of much help. But despite all that I was nevertheless able to concentrate on stage 2 wind noise and deemed it exactly the same that my 330d has. At 240 kph the wind noise is extreme in both cars - you cannot hear anything else.

The demo car had an older side mirror ridge design.

Well, what can I say? I am yet to test-drive an F10 this or next week for comparison, but seems like the wind noise level of the whole F30 generation is an inherent part of its design. The logic here is probably: if you want less wind noise, buy a 5 series.

Let's see if the member Anaskh might have any news on the new side mirror cap design (see his post above), and whether somebody would want to dismount the side mirror and do the test. As for the rest, I will conclude the investigation when I have test-driven the F10.

[bluemark81]

Originally Posted by lightyear36

Short answer: seems like all F30s are noisy by design. People stating they have no wind noise at higher speeds most probably came from E90/E92, which was similarly noisy, therefore this is normal for them.

Neither of my e90's had wind noise. They certainly did not have what I would consider to be unusual or unexpected levels of wind noise. I actually find other areas of the car to be reasonably quiet to very quiet. Engine noise is not bad at all. Yes, it roars at full throttle, but not what i would consider obtrusive for short term bursts. Road noise can sometimes be intrusive depending on the road surface.

Your findings is what I was afraid of.

I asked my dealer about new mirror housings and they have no knowledge of this.

[lightyear36]

Originally Posted by bluemark81

Neither of my e90's had wind noise. They certainly did not have what I would consider to be unusual or unexpected levels of wind noise. I actually find other areas of the car to be reasonably quiet to very quiet. Engine noise is not bad at all. Yes, it roars at full throttle, but not what i would consider obtrusive for short term bursts. Road noise can sometimes be intrusive depending on the road surface.

Your findings is what I was afraid of.

I asked my dealer about new mirror housings and they have no knowledge of this.

I didn't have a BMW before, so I cannot compare with E90, but you are suggesting that relative to F30 at, say, 140kph, the E90 is quiet?

I don't mind short bursts of wind noise, but 330d or 328i or 335i is a car you drive at high speeds on the highway - maybe for 1-2 hours if the commute is long enough. 2 hours of serious swooshing is not what I imagine being "premium".