Re: Vibrating of buffeting of windshield wipers
On my 2014, I had a similar issue at highways speeds after a service repair where I was getting a fairly violent vibration and buffeting at highway speeds.
Turns out the dealer had removed the plastic cover piece that sits between the wipers and the engine bay seal (The piece that contains the AC intake grill) and when they re-installed it, they didn't re-seat it properly. I was able to pop the hood and easily snap it back into place and make sure it was secured at all points and that did the trick. Could be something different in your case but hope that helps and good luck.