I was getting a vibration at 70 miles per hour. The vibration would start at 60 mph and then the peak seemed to be right at 70. I had the wheels/tires Hunter Roadforce balanced by two different reputable tire dealers. It seemed to improve things a little but there was still that vibration. My MKT is right at 49000 miles or 1000 miles away from the factory warranty expiration. First, I went through the internet and there was a consensus that this issue might be related to the driveshaft or rear differential but not the tires/wheels. Many owners got a Roadforce balance which did not solve the issue. Second, since Im 1000 miles away from the warranty expiration I decided to place it in the dealership where I left them with a letter stating I thought it was the driveshaft. They called me up and said they are replacing the driveshaft. Many owners in years past also stated that when the dealership replaced the driveshaft it did not cure the problem entirely. Some owners stated the entire rear differential needed to be replaced. While some others stated even with both replaced there still was a vibration problem although not as much as before. Finally, there are Lincoln MKTS out there which have been bought back under the states Lemon Laws as a result of this vibration and the dealerships inability to fix it. Thus the best an owner can do is Roadforce Balance the wheels/tires. Replace the driveshaft and possibly the rear differential. However, that might not solve the vibration problem.