Schweinfurt is the largest ZF facility in terms of employees, and you really get a sense of the volume ZF produces when you are there. Nonetheless, I felt a sense of family there. People were proud to be at ZF (or Sachs as some still call it), and they were always welcoming (both in and outside of work). The vibe at Schweinfurt is quite casual, but nonetheless people work hard (and efficiently!) and things get done.
Secondly, I worked in Friedrichshafen, which, as the headquarters, had a much more corporate vibe than Schweinfurt. The dress here is a bit more formal, running between plants is a part of life, and the pace here is fast, as to be expected from HQ. Nonetheless, people are friendly, inclusive and inviting. Also, as a city with a prime location on the Bodensee, nature abounds, and this was one of my favorite parts of living in the area. I participated in a ski trip with my department, did frequent runs along the lakeshore, and took part activities that go along with the lakefront living.