It happened in Ida, south of Ann Arbor.
Austin Smith and his grandfather Ernest "Papa Ernie" Monhollen were working on the vehicle which was being held up by cinder blocks.
The vehicle slipped off the blocks while Monhollen was underneath.
Smith picked the vehicle up high enough for the older man to escape.
Monhollen suffered a cut to his face, a broken eye socket, and broken ribs but is at home recovering.
Smith says he doesn't know where the strength came from to lift the vehicle.