Transmission Chatter

Hi everyone, I didn't post this in 911 because I'm not using the truck much at all this month and want to get some more information.

We have a 2007 2500 MegaCab with the cummins 6.7. The truck only has about 1200 miles on it now, we bought it with about 200 miles new off the lot last month. Here's the problem, after getting to about 250 miles, we felt a generous vibration under light/mid throttle off the line. The shaking was only apparent from a stop and almost like the transmission is quickly changing from 1st to 2nd gear or back. After three days of owning the truck it was back at the dealership and they were trying to diagnose. They said nothing could be done because chrysler was working on an update for the transmission. OK

2 weeks later the dealer calls and says they are ready to program the trans and to bring it in. They gave me a rental and I was on my way. 2 days passed and I get a call my truck is ready. I go to pick it up and I find a huge ding in the driver door (looks like somebody swung open the door and hit something, paint missing and everything). The transmission "chatter" was gone but a hard shift from 2nd-3rd replaced it. The tech quickly recognized it and said there was a TSB for that hard shift and all it would need was a "quick-learn". That done, truck went to the body shop (on the dealers dime of course). Picked up the truck and everything appeared to be working great.

Now the truck has about 1200 miles and the transmission chatter is back and more apparent. Before I take it back I was looking for information on this problem and wondering if anybody had heard of this. I've done a couple searches and I may be doing them wrong because I don't get many results, just stuff on using the tow/haul mode which we haven't even tried. Thanks for any info.

- Wil