mattiz

Hi everyone,

I purchased a 2020 AUDI A6 Avant (used) a few weeks ago. A few days after purchase, I noticed a noise that can be heard during acceleration phases from a standstill with the wheels turned, both to the right and to the left. It does this for the first 30 minutes or so of use, then it stops. You can't feel anything from your hands, it's fluid and normal.

My impression is that the noise has the rhythm of the rolling of the wheels.

I had the noise listened to at an AUDI Service, who told me they had never heard it, so they made a short video with their smartphone and sent it to AUDI.
AUDI replied that it is a normal operating noise, but I assure you that it is not: probably the video they had made was not able to capture the sound well.

Now I made a video with my smartphone. I link here both the version with the original audio and the version in which I isolated the noise using software.

Original:

Isolated:

Unfortunately, smartphone microphones are not the best for these measurements.

Can any of you help me? Thank you very much.

I conclude by saying that I believe the AUDI service was unprofessional. You cannot send a customer back and leave his problem unresolved.

John Simcox

How worn are the treads on the tyres and are they same brand and/or mounted correctly if they are unidirectional? Could be that noise goes away once the tyres have reached a suitable temperature and therefore have more flex in them.

mattiz

The tires are quite new, a few months old. Do you think it could be a tire noise? Have you ever heard a similar noise?

HNeves

I had the same problem in my A6 40 TDI 2019 and the solution was change the MTF oil from the automatic transmission. I had to change too the oil pump (from the automatic transmission) because of a small leake.

Waap

Had it on my audi as well. Under warranty changed oil, reduced the sound came back shortly after then dealer claimed its work of art...

mattiz

Oh wow, thank you for your reply. If this is the reason I am truly grateful for your comment. It's probably ATF instead of MTF.
1- Did you hear exactly the same noise as in my videos?
2- Did it disappear for you too after about 30 minutes of use?
3- Did the problem no longer occur after changing the oil?

Thank you very much if you can answer me again. Greetings!

mattiz

Thanks for your comment. Can you explain better? I don't speak English well and I can't understand the meaning of the sentence quoted here. Thank you.

HNeves

It's the MTF. The automatic transmission has ATF (with periodic changes) and MTF (without changes, according to the manufacturer). You have several videos in youtube that explains how it works. In my case, they changed the MTF and the noise disappeared (it has a few days since that change). The noise is the same as your video, the difference is that only appeared when I turned the wheel to the left side. The noise only appeared with cold engine and when the temperature of the atmosphere was low.

mattiz

ok, thank you very much for your reply. Did the repair cost you much (excluding the oil pump)?

HNeves

It was under warranty