BluByU14

Guess I spoke too soon.....on my drive home, noticed it again, but feels like it is even worse. So weird that it is an issue that just seems to come and go without rhyme or reason. Got a call into the dealer to take it back in.......... If I had known I were going to have these unsolvable issues, I would have never bought the vehicle.....feeling pretty sick right now on a $50K+ truck. We'll see what happens next!

Well within seconds of me posting the last post above, the dealer called and said my truck was ready. They roadforced all of the wheels and tires. One of the tires was replaced and the other 3 wheels were re-balanced. Took it up on the highway and the truck does feel much better. There is a slight vibration/bumpiness at 73-75, but I am thinking that is from the roadway. Took it up to about 88 mph without any issues. Hoping there aren't any further issues!

Just dropped my 2014 GMC Sierra (w/ 1400 miles) at the dealer to start investigating this vibration issue. I will say that the vibrations I am feeling sound minimal, especially in comparison to some of the posts I have read on this forum. Mine are mostly in the seat/floorboard and are only felt between 70-85 MPH. The vibrations on mine also seem to come and go. Some days on the same stretch of road it fine, others it is really bad. Praying they can at least minimize it to a tolerable level without multiple trips, runaround from service dept, lawyers, buybacks, etc. Will keep everyone posted on the findings!

So I have had my 2014 SLT Sierra for less than a month now. Just broke 500 miles this past weekend. In the few highway trips I have taken, I immediately noticed a vibration coming from the rear of the truck. The steering wheel feels fine. I notice the vibration in the seats and can notice my empty passenger seat rocking back and forth pretty good. The vibration level varies and is most noticeable between 65-80 MPH. At first I thought it was the roadway or just me as I was coming from a 05' Yukon Denali, which had a much smoother ride. My truck came equipped with the the Max Trailer Package, so again I thought this may have been normal based on the trucks characteristics. After reading this thread, I am starting to doubt that it is "just me". I have a call into the dealer now to schedule an appointment. I have tried to read as many posts as possible here to figure out what my exact issue may be, but based on the posts, it looks like it could be a multitude of things (transmissions, tires, wheel balancing, drive-shafts, rear-ends, etc.) Can anyone give me any good advice to help "steer" the dealership in the right direction on where to start looking for potential issues? I just dont want to lose the truck for any extend period of time or have them potentially tear apart my drive-train to come up empty handed. Here the specs on my truck: Built in May of 2014 6.2L with a 3:73 rear Double Cab with Standard Bed. 20" wheels with the stock Goodyears Thanks for the any feedback!