Detroit, MI to Milwaukee, WI buses and trains from $57

Or, see buses and trains from Milwaukee, WI to Detroit, MI.
Here are some trips other travelers have found on Routefriend.
9h 6m
1 stop
8h 16m
2 stops
Amtrak Greyhound
12h 49m
4 stops
Amtrak Greyhound
9h 10m
1 stop