[RT14Ken]

I've seen plenty of posts from members concerning rear end clunking with their M6 R/T's, but I have a '14 R/T A5 where I get a clunk and a bit of a jerk when coasting down then reapplying throttle (at lower speeds most noticeably). Never had this problem with my '13 V6 A5. Just for fun, I disabled MDS with my Diablo and the problem seems to be largely resolved, greatly improving driveability. I realize, of course, MDS isn't related at all to the tranny or diff...I'm just speaking about how they all interact dynamically as a system. It's like coasting down while in MDS then hitting throttle was causing some weird driveline resonance...MDS disengaging while tranny is trying to downshift. Anyone else notice this problem with their A5's or have any other theories?

 

[BAD GRANDPA]

No problems with my 2010 (31,000 miles). I'd put back the factory tune and enable MDS and any other settings you changed. Take it to the dealer and go for a drive with their tech.

 

[BobzCar]

Check the bushing above the rear differential. Difficult to see, but thats what went on mine. Its a cheap part. About 20 bucks. Quick check if you tighten the bolt that goes up through it, and take a drive, if the clunk is decreased, you found the issue. They are kind of thin and not too beefy, mine fell apart. The bolt is a long one that goes straight through the rear end housing, the nut is welded to the bushings retainer on top. You can get to the nut with a breaker bar and a deep socket. I replaced mine in 15 mins on a lift. You dont have to drop the rear cradle. Its just a PITA to reach.