Why does Ford, the manufacturer, have that many mechanic positions? Any mechanics employed by dealerships are employees of that dealership, not Ford. On top of that, vocational schools - which frequently include auto mechanics - are plentiful in the US. I am confident there is one in every major city in the US. Any high schooler has a direct pathway to that career. But it almost never pays $120k.

I suspect that they aren't looking for people that can repair a car using provided tools, documentation, and training. Instead, these are likely to be Mechanical Engineers - people who can design the cars/tooling, or who can analyze/predict failures that are occurring in the field. They may also be analyzing whether a failure is covered under warranty.