Your query needs to be posted in the St. Clair County Michigan section, this is the Emmet County Michigan section. PFC Gleason's home, either in Emmet Village or Emmet Township, was located in St. Clair County, Michigan in the southeast corner of the state.
I have found a John Gleason of the right age and residence in the just-released 1940 US Census. On 1 Apr 1940 John Gleason, age 18, was living with his widowed father Thomas Gleason, age 62, who was a farmer working his own farm. John Gleason was born in Michigan, while his father was born in Ohio. John was employed as a farm laborer.
Other members of the Gleason household were John's sister , Emily Cavanaugh, age 23, her husband William Cavanaugh, age 27, and their children Peter Cavanaugh age 2, and William Cavanaugh age 1.
Good luck in your search. It is quite possible that PFC Gleason's nephews Peter and William Cavanaugh are still living.