I just bought a 2015 v8 S, and on the test drive it was great, but in the week or so since then it's slowly developed a rubbing sounds on turns and a clunk that has gotten louder and louder the more i drive it.

The clunk sounds like something under the center armrest (not in the armrest... i checked ) is clunking back and forth when i get on and off the gas, almost like a motor mount or exhaust mount clunk.

The rubbing sound seems to only happen on (right?) turns, but it is sporadic, it is a speed sensitive sound that sounds like something is rubbing against the tire when i turn.

I've played with different speeds and steering angles a bit, but since its CPO i plan to take it to the dealer tomorrow. Just curious if folks have run into this before or if I'm missing something easy and obvious...

 

It is very likely a bad differential.

 

What Unhingd said. The description you gave sounds very similar to the noise mine was making, which turned out to be the differential.

 

My 2016 R has just developed this clunking/rubbing noise when turning left or right at speeds below 10 mph. I will definitely get it checked on my next service visit.

 

So just came back from the dealer and they the differential carrier bolts had worked themselves loose, nothing otherwise bad and no other damage. Fix was... tightening the bolts. Very odd, given i just bought the car a few days ago and it passed a full CPO inspection, it makes it seem like there was work done under there (maybe a diff replacement). Also odd that the dealer had no service records for the car. Oh well, CPO warranty for another 2 years so i'll just keep driving it and hope for the best...

 

You can also check for broken bolt on transmission mount.