I know that I only have a few post on here, but I do follow this forum on a regular basis just to see if anyone has come up with a miracle. I won't go into detail, but I was test driving a new 2015 slt sierra (I have a 2015 sle now) and it vibrated worse. I got on the interstate for my hour drive home and immediately got off on the next exit and returned to the dealer. Told them no deal, it's worse than what I have now. They all looked shocked...lol What are the odds that out of all of the trucks on the lot,I pick the one the vibrates. I'm starting to think the odds were pretty good, because there are probably a lot more vibrators out there than they will admit to.