If the tires are worn, replace them. Belts can separate inside the tire causing the wobble. If wobble still persists after replacing tires, you have narrowed down the search and installed safer tires. Can't lose.

__________________
2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900