The pinging, knocking, or rattle I am getting on moderate to hard acceleration.
Had it to the dealer, and they were not only really nice about it, but when they could not "verify it themselves" they had me take a tech around in it. He could *hear* it, and agreed it was very quiet, but he felt it was just normal operating noise. So then they let me take him around in a comperable V6 AT 2013 they had on the new lot. And there it was - the 2013 made the exact same noise at the same times. But the 2013 was even louder! I said "I will keep my 2012, thanks!"
To jump to the conclusion... it turns out it is an exhaust resonance vibration that occurs in the forward exhaust in all 2011-2013 V6's. And I am just being too sensitive to car noises. :nogrinner Normal operating sound. Just that I have had over 20 cars older than me, and I have learned to listen to noises the car makes. Now i just have to get used to it.. or do an exhaust change. LOL
Hope that helps others that do a forum search! Thanks all, it was an interesting discussion.
2012 V6 AT 3.31 base Grabber Blue
'83 DJ5 (Postal Jeep)
...and a long history of unusuall cars.