'16 Escalade Platinum owner here.....
I posted in this thread over a year ago as I had an early build '15 Escalade Premium with the vibrations, buffeting, booming, ear pressure problems. Quick recap on it. The dealer tried everything described throughout this thread including 2 rear differentials, 2 sets of Bridgestone tires, on set of wheels, driveshaft re-balance, new MRC shocks, struts, roof bows, and some other items I can't recall now. GM finally agreed to replace mine, and I insisted on a '16 as I had read here and other places that the '15i was still experiencing the same issues, and more what with the new 8 speed transmission bringing a new set of problems to the table.
Finally took delivery of a new '16 Platinum last fall, and it was a breath of fresh air. Only problem was slight ear pressure and buffeting in V4 mode, probably wouldn't notice if I weren't actively listening for it.
Flash forward to Christmas and the vibrations from 30mph-80mph had returned and the ear pressure and buffeting becoming more pronounced. Discussions with Service Manager began.
After some back and forth on his part with GM, the torque converter on the transmission was replaced and A NEW SET OF MICHELIN PREMIER LTX TIRES installed.
Unbelievable what a difference this had made. No more flat spots. No more booming except for situations where you would expect a BOF truck to make those sounds. Most of vibrations eliminated, but not completely. Yet anyone who has driven any BMW of Porsche would find my truck perfectly acceptable. But for those of us accustomed to a "Cadillac Ride", its still unacceptable on certain stretches of road, mostly in the 30mph-50mph range.
Torque Converter all but eliminated buffeting and ear pressure, which occurred 99% of the time in V4 mode.
Finally love my truck again! Now if I could find someone, GM, WeatherTech, etc. who makes an all-weather floor mat to match the Peanut Butter interior.....