The only way the lawsuits have merit is if the attorneys can prove that Ford gamed the EPA test, and that in fact they don't get 47mpg when tested according to the regulations.
But EPA has not come out and stated that Ford's tests are invalid, the way they did with Hyundai.
The issue is, I think, that the vehicles get great (and probably repeatable) results in the lab, but in the real world they are sensitive to environmental conditions and driving style.
This puts Ford, and other OEMs, in a tricky spot, because they are required to advertise the EPA mileage on the new-car ("Monroney") sticker. The usual marketing jargon "up to" and "your mileage may vary" is deployed, but people still get the idea that the EPA number is what they should be getting.
Decorate your car with magnetic signs.