ffejrey

Please help me, I can not sleep at night and I want to love my Audi A8L so bad!!! Sorry for the long post but I promise it's entertaining and informative.

First of all thank you all for reading this and having such a great forum and resource for everyone! Kudos to all. I would love all D4 owners (and those familiar with the car) insight and experiences regarding an ongoing issue which I will solve one way or another; at this point I am that determined.

I just purchased my first Audi about 2 months ago, A 2011 A8L with all the bells and whistles. What a wonderful car... except -- first time I got on the freeway the car made (and still makes) a harmonic humming noise, very road surface dependent, which has become now the biggest frustration in my life. This noise happens mostly at freeway speeds with the stock 20" tire size...

Cutting to the chase, after 2 months I have driven 3 Audi A8L's all with 20" wheels (2 2011's and 1 2014 TDI) and all cars exhibit the same characteristic - I firmly believe the issue is the strut or something closely related... not the tire/wheel combo as Audi claims.

I have always maintained this "humming/droning/hollow donk" noise that I am hearing is road vibration translating to the front end of the car and something Audi down the line in the strut is acting as a tuning fork emitting loud annoying harmonic noises (which under the right circumstances even drown out my B&O stereo on 20). I also acknowledge that everyone's ears and sensitivities are different, and while I might be disturbed by this noise others don't really hear or care about it. With that said, this sound is so obnoxious (and present I believe on every A8) I would love to raise awareness and join forces with others who may not completely understand what is happening and "believe" what Audi has told them if they have complained -- which is: the noise is a 'characteristic of the 20" wheels/tires' and "normal."

Starting at the beginning, I first brought my car to an Audi dealership (under what little warranty I have left) because of this sound soon after purchasing. I was told this is "normal" for the 20" tires I drove it for a couple more weeks. The noise however got under my skin quickly and I became so frustrated I found a local Audi specialist mechanic to help. First, however, I told the dealership I was going somewhere else because I was not satisfied with their response. I was told by the service rep at Audi to return the car to them because they have "chassis ears" which would help determine where the sound might be emitting from. Left the car patiently for 9 days only to be called and told "we drove the car and we say it's tire noise." 9 days.... Honestly... When I asked about the chassis ears they said because they are so confident the sound is tire noise they will not use them.

I believe they did not want to use them because they work and would identify where the sound is being truly emitted...

Then I was told with 19" rims the tire noise is eliminated. They even put 19" wheels from a loaner A8 on my vehicle to show me the sound reduction... The key here is reduction, in no way did the "cushiony" tires eliminate the problem. Not to mention how much it changes the dynamics of the car...

I emailed Continental tire in NC and told them I feel Audi is throwing them under the bus about an issue I am having and described my situation... I got a call from a "Product Service Engineer" at Continental (who is simply and amazing individual and am now very impressed with Continental as a company) who talked with me for at least 20 minutes. Obviously the gentleman couldn't confirm the noise as one or the other over the phone but he told me if there is a harmonic interplay between the car and tire a different size tire would change at what speed the harmonic occurs, not eliminate it.

I changed my tires to see if by chance Audi was correct, but I changed to a 275/40/20 over the 265/40/20 stock size because only Continental and Pirelli make one tire each in this size and I have heard numerous reports that Pirelli's (and a few reports that the Continentals) are loud tires. I purchased Goodyear eagle sport A/S after reading many positive Tire Rack reviews all saying the tire is very quiet...

Guess what?!? The Continental engineer is correct. Now I have the same humming/droning sounds from 20-40 miles and hour and much quieter on the freeway 60-80 -- however it is definitely still there and it is the same frequency noise.

Today I finally sat in the back seat of the car while being driven.... no humming/harmonics in the rear - all harmonics are occurring in the front of the vehicle. My local trusted mechanic agrees the sound is not solely tires and also believes the struts (and/or control arms etc.) are the issue.

Finally I found this random consumer complaint posted:

1 Complaints: 2012 Audi A8 High Pitch Noise From Struts

"Audi A 8 has STRUT DEFECT - Car makes very high pitch noise when you go over sloppy roads or speed bum bumps - Audi is telling me that the STRUTS have a problem on most of the Audi A 8's and not sure if they can fix the problem because they had defectice STRUTS that they purchased from a Manufacter.

This is very disturbing and I believe there is a cover up - I met with Audi regional manager who ADMITS there is a huge problem with Audi A 8's and they have to find new struts to put on the cars.

My car cost over $100,000 and Audi had bulletin Noptice on the A8 regarding this problem."

I am starting to believe this is actually a true statement.

I also have a ".m4a" recording of the sound however when I try to attach here is says "invalid file." Any help is appreciated, you can clearly hear the noise on the recording... The sound is a midrange/upper frequency, it is not the flat tire noise we all know.

Thoughts? Stories? Help? Please??? The car is so amazingly dynamic in every other way, all I want is to put this issue to bed. I even found a sound proofing specialist who sells a paint product which acts like dynamat and dampens vibrations (used on naval ships...). If I can locate the issue this may help, or at least I dream it will...

**Also to note - when they put the 19's on my car, they put my 20's on their brand new 2015 A8 loaner. I begged them to let me take the loaner for a day... they did (which was nice of them...). The 2015 with my tires in no way makes the same noises. It is also noteworthy that the redesigned 2015 uses "taurus mass dampers" in the front strut not compatible with 2011-2014 models), added noise insulation and noise cancellation to the car... Wonder why!!!!

Thanks to all for reading my book and I look forward to your feedback.

ffejrey

Also to note, at the same frequency, sometimes left front - sometimes right front, over bumps, the struts make a hollow "donk" like noise over bigger bumps. Again all 3 a8l's I drove do this on So Cal freeways. The donk/bonk hollow noise does also occur over bumps when car is not noticably humming/vibrating.

needles

The only time I notice this is when driving over roads that are in the middle of being resurfaced where there are noticeable half-inch grooves carved in the pavement running parallel with the road. The car exhibits (any car) a loud whine that changes in harmonics with every slight movement of the steering wheel.

Are SoCal roads grooved permanently?

ffejrey

Yes they are in many parts from San Diego to LA and LA itself is horrible. It is absolutely road surface dependent. My hypothesis is certain road surfaces cause road vibration via the tire/wheel which is transferred to the vehicle strut and related assemblies which become tuning forks and hollow echoing chambers (the air strut and hollow aluminum strut components are currently suspected). The rear does not make noise before and after tire rotation; it's the front of the vehicle.

When I changed tires however to 275/40/20 from the stock 265's both the road surface and speed changed when the car sings and hollow bonks. Now the car does not hum *as loud* on freeways but is obnoxious from 15-40 on black top roads now. The tires are butter however, feel much softer than the continentals and beyond the harmonic are a smoother rolling tire with obviously new rubber. As explained to me by the sound engineer at Continental, harmonics will change with tire size and my car now has 4.3" sidewalls and a 1.1% increased rolling circumference. With the 19" tires it is a 1.1% decreased rolling circumference with 255/45/19 stock tires... Therefore I assume the sound occurs under different circumstances with the 19's and the 4.5 inch sidewall also mutes vibration transfer to the vehicle.

The 20's really exploit the issue and the sound on the right road surface is most noticeable from 60-80mph. Again yes, I have heard the sound the loudest on freeways with grooves but once you identify the frequency and get to know the sound -- you will hear it all the time when your stereo is off... Unless I have Spidey hearing... I do not want to subject yourselves to the same annoyances I have now but again once you identify the sound you will hear it more than you thought. I believe many attribute it to tire noise however this noise is not flat and not from the tires... It's our air suspensions and Audi's employment of "ultralight technology."

As a cruel and horrible "joke" watch this :-/

http://www.google.com/url?sa=t&rct=j...76247554,d.cGU

needles

I've taken several hundred-plus mile trips in my A8L and it has to be the single quietest car I've ever driven... My Infinitis were always quiet, but the A8 is a whole new level of isolation. I do not have the dual-pane glass either.

I'm still curious as to what you are hearing, though.

ffejrey

Interesting... I can't tell you how jealous I am! And I do have the dual paned glass. On certain smooth black top the car is very quiet; I am sure different areas of the country have much different composition/condition freeways and streets.

Do you have the 19" wheels/tires? The 20's definitely make a big diff harmonically.

I will make my .m4a file able to upload so you all can hear...

Jeff

needles

I have the 20-inch wheels and P-Zeros. By all means, share the file somehow.

jakematic

I hear the hum when I hit certain grooved roads in SC.
Drove me up a tree driving a long stretch in Ohio recently.

I blame the tires and size of the wheels.
Like the 'whoop' noise we have to learn to live with it, but should get it documented by an SA while under warranty purely as a CYA.


Comments like these always crack me up:
Nothing and no-one is 'perfect' and the definition varies.....


Post a video to YouTube if you want to share the sound.

ffejrey

Here is a link to the youtube video:


It may be a stretch but I believe the my hum and the "whoop" phenomenon may be related and as your strut ages it will get worse... like mine. Now that I think about it when I leave my garage over the first bump it makes the same noise it makes humming and donking down the freeway...

Just out of curiosity why does my comment about the price of the vehicle crack you up? (Besides the fact we all know what these vehicles MSRP'd for...) I could more understand the r&d being limited for a "budget" vehicle however a flagship sedan from a premium manufacturer should not be defective or subject to issues every other car manufacturer can successfully deal with. In my discussion with continental tires, harmonic/vibrational interplay between the car/gearing/tires is taken very seriously and researched/understood on every car. I am not going to give more detail now because I want friends not enemies however I will say I have received information from inside the Audi service department that the struts are what is making the sound. Don't believe me? Find a stretch where the cars hums, then sit in the back seat and be driven down the same stretch... I did. The hum is only generated in the front of the vehicle...

Regarding documenting the event I have... twice now. But how does it help if we can not identify the issue? Audi will give us the same song and dance... If any of you have any suggestions or insight from the youtube link please, please let me know. Thanks!

ffejrey

Sorry - I didn't say that... :-P Silly me, I wrote such a long opener I forgot what I said and what I quoted from the consumer complaint site. His comments do come off a bit pompous...

Moving on -- please, please tell me what you think of my noise and sorry about the loud music for the first 5 seconds... That's how loud the stereo is however and I still hear the noise!!