I have been back to the dealer more than 8 times. Tires balanced, rotated, and then done again. The GMC technical rep even requested the vehicle be sent to a different, larger, dealer to do the same thing. Vibration continues. It is NOT the tires.
I am convinced it is the Magnetic Ride Control. Vibration is easily noticeable at all speeds, from 10 right on up to 80. More noticeable when even a slight imperfection in the road. I've had individuals ride in the car actually say, "your car has the Shivers!"
GM has said -- the vibration is within parameters of similar vehicles. CASE CLOSED!
I am so fed up with this vibration... should NOT happen on a $70,000 Vehicle. The dealer has 3 times rented me another GM product while they worked on mine. All three were cheap (under $40k price) vehicles, and ALL road smoother than this 2016 GMC Denali
I love the car/HATE the vibration. I travel a lot... and with now 6,000 miles in just 4 months... the vibration is simply getting to me. You can hear it! Feel it! and cannot get rid of it.