Sparta

My A6 recently started intermittently making a low volume whining noise, seemingly coming from the front of the car. I only hear it while moving above about 15 mph. Once slowed down to under about 15 mph the noise seems to trail off. I can sometimes hear it on the highway at 60 mph. The pitch or the volume doesn't change with speed, it does not stop when the brakes are applied or when the steering wheel is turned. The ventilation and radio are both off. I cannot hear it when the windows are open. I have checked all the rubber around the windows and they are good condition and clean. It doesn't always happen, but seems to be slightly louder in the morning when the car is cold. It may stay on for the whole trip, or not.

I have attached an audio file from the morning when it is loudest. It is still pretty low so you will have to crank up the volume a bit, but don't forget to to turn down the volume when done.

Anyone heard something like this? I am thinking wheel bearing....

KevinGary

I am guessing a wheel bearing.

DanfZX14

I'll go with a + one for that

DB22

But the pitch doesn’t change with speed.

KevinGary

OP said noise trails off below 15 mph.

DB22

Agreed but he also stated that it doesn’t change with speed.
OP, I think it’s time for some professional advice, let us know what you find.

engleg

I'm not sure if the OP is going to chime back in or not?
If it is a bearing going bad these were the symptoms I
experienced when my front driver's side wheel bearing failed.

https://www.audiworld.com/forums/a6-.../#post25026176

Sparta

I was out of town for a few days...

I did bring it to the dealer and went for a ride with a mechanic. He heard the noise but it was very faint. He said it could be a wheel bearing or possibly a caliper, and rather than spend money on diag time to wait until it got louder as that would make it easier to find. They quoted $325 to replace a bearing on one wheel. I will update when I figure it out.

Thanks for the input!

Vodka G

i did put $5 bet on wheel bearing

DB22

Putting $5 on it “could be” a wheel bearing is different than putting $5 on it “is” a wheel bearing. You will have to wait to see if you made any money!