the_duke

4.0t mount looks similar.

derfA8L

Can't imagine why they would be the same, unless the supercharged V6 needs them to smooth it out... but I'll ask when I bring my car in for a service appointment on Saturday. However, the description for Audi active motor mounts is mentioned only for the 4.0T V8, not for the 3.0T V6. From the 2013 MY A8 press release (when both 4.0 V8 and 3.0 V6 engines were introduced):

Audi cylinder on demandTM technology* Audi cylinder on demand technology with active motor mounts and noise cancellation improves mpg up to ten percent. With transitions in less than 1/400,000 of one second.

1. Two active motor mounts use crankshaft position sensor and built in accelerometers to detect normal V4 vibrations between 25 & 250 hz; motor mounts are electromagnetic coils (similar to speakers) incased in hydraulic uid which transmit opposite phase vibrations to cancel incoming vibrations from passing through motor mounts. These mounts also work during V8 idle and over rough roads (low frequency vibrations between 7 – 15 hz).

2013audia8

I had this issue. I have a 2013 a8 3.0 that I purchased a few months back with about 40k miles. After noticing the shudder/vibrations, I took it to the dealer and they were at first a little baffled. They ended up replacing the flex pipes. That fixed the problem for a while, though, I have started to notice a little bit of shudder

porboy44

I took the car to the dealer to have it looked at. They had the car for 1.5 days. They were able to replicate the concern and told me that they spent quite of bit of time trying to track it down and found nothing. They said that they went and drove a new one in inventory and that it did the same thing and thus concluded it was normal and nothing was wrong.

MTL-AEight

Hi Guys,

just following up on this issue, i seem to have it as well,

it is very specific only under load ( meaning if i put the car on a lift and drive it, the issue is gone)

when i accelerate somewhere around 1200rpm, i can hear the vibration. also when i accelerate up to any speed and just let off the gas, as it comes back down the rpm band, when it gets around 1200 i can hear it.

possible causes,

Engine mount ( which one i have no clue, i would suspect they would throw codes)
transmission mount ( also i would suspect codes, and or clunking noises or something)
Flex pipes ( i could change these pretty easily)

any other possible ideas, my warranty just ended, but i have my brother garage. just trying to get some guidance.

i have read a ton on this, but most of it is for the other models outside of the 3.0t supercharged

any thoughts before i bring it to the dealer, i am pretty sure they have seen or heard of this issue.

rally

I had a similar issue 2011 4.2 with vibration when letting off the throttle when the rpm's would reach about 1,200. Flex pipes in exhaust have an inner liner that vibrates. Replace the flex pipes and it goes away.

MTL-AEight

Thanks a ton, this is the part that for some reason i would always focus on while under the car.

did you replace it with OEM meaning the complete convert pipe part, 4H0253300H, or did you just have the flex pipe cut out and replaced?

MTL-AEight

also if you just cut it out, does anyone know how to tell the size to order, ebay or other site? or if i bring it to a muffler shop, i assume they would be able to replace these pretty easily, at much lower cost than replacing both these with stock parts.

rally

Muffler shop replaced with their flex. I volunteered to get OEM part but they said not necessary. Less than 2 hr job.

porboy44

I took the car back to the dealer as the 1200 RPM vibration was annoying and I was fixated.

Regardless of speed or gear, there was a vibration at 1200 rpm. Even did it if you were in park and reved to 1200.

I put my phone under the car and recorded video while i reved to 1200. You could clearly see the flex pipe vibrating, to the point that it was blurred in the video. You could also hear a small exhaust leak on the video and see that the mesh in the flex pipe wasn't quite like it should be.

Dealer replaced both exhaust pipes containing flex joints, 4H0253300H and 4H0253350N.

Vibration is gone