That’s bizzare; those would have to be unionized plants. Ford couldn’t turn a profit with unionized plants. They’re probably just robotized assembly plants, not actual parts manufacturing plants.
http://www.courier-journal.com/article/20100128/BUSINESS/1280322/1003/Hourly+workers+at+Ford+will+get+first+profit+checks+since+2005
Furthermore, those plants include both component manufacture and whole auto assembly. The Buffalo, New York plant makes sheet metal body panel stampings, the one in Brook Park, Ohio is a casting facility that makes engine blocks and crankshafts, while the Kansas City Assembly puts out a variety of products including the F-150, Escape, Contour etc. and the Chicago Assembly Plant makes the new Ford Explorer, for example.