Here is the fix I found for a vibration.....may be same thing. Try it and see if you truck still makes the noise/vibration.
Here is a link to where I posted this info with a pic. Look on page 2 towards the bottom. Two pics were loaded in that post.
Well.....discovered the noise. And fixed it! Here is a copy of what I posted on another RAM Forum.
I did...... They still acted like after I left they couldn't make the noise happen like I did.
However.......TODY WAS MY LUCKY DAY!
I went out and listened to my noise with the windows up and it sounded like it was coming from the front passenger side.
And since it sounds like metal vibrating....under the truck I go. Here is what I found.
The only metal part I found that could be loose was a muffler clamp right where the two down pipes from the motor come together and clamp to the straight pipe going to the muffler. It's the only clamp like it on the exhaust. The other one by the muffler is different. Anyway, the clamp nuts were as tight as heck. I couldn't even budge them using a pipe over the end of the wrench. So I checked that idea off my list of one thing to check. But then I noticed it...... Right above that clamp, welded to the top of the muffler where that clamp is, is a flat clip that is bent kind of square and it goes over the clamp, evidently to hold the clamp in place during manufacturing before it actually gets put together and tightened down. Well it's only welded to the exhaust pipe on one side of the clamp. So the other side vibrates. Evidently around 3500 RPMs. Lol! But since its over the exhaust clamp it vibrates on the metal of the clamp. I went under the truck with a very large screwdriver and put it under that clip and pried it up until it was totally clear of the clamp. Now VOILA! No vibrating noise!
I'm so glad I could lose control. This noise has been haunting me since I got the truck. And four trips to the dealer with no fixes.
I feel like I need to go dealer and show them the culprit. So they can help anyone else who may have this issue. Cause clearly they'll never figure it out on their own.
Hope this helps someone.