Hi Bernadette,
I've found that Grabanski is a rare name in the U.S. My husband's family came from Konefki, Poland to North Dakota in 1892. The immigrant siblings were John (d. 1932), Steve, Joseph, Frank and Lillian (d. 1971) Grabanski. As the story goes, Frank and Steve changed their surnames to Smith because of trouble they'd had with the Germans during the WWI occupation. They stayed in the Chicago area instead of following the others to ND. I've looked through my records of the American Grabanski's and didn't find any in Detroit. I wonder if Frank and Steve went back to the Grabanski name?
Perhaps their descendents moved to Detroit? Long shot, but what the heck. Have you looked for other Grabanski's in the phone book? I haven't met one yet that wasn't related once I got to digging. Good luck.