He was driving a 2006 Volvo tractor-trailer east on Ohio 303 when at about 1:30 p.m. the truck drove off the right side of the road and overturned, troopers said.
The crash was just west of Hanford Road in Huron County. Parker was wearing a seat belt. He was taken to MetroHealth Medical Center in Cleveland, where he remains in critical condition.
Transportation crews shut down the road so they could remove the tractor-trailer and the steel coil it was hauling.
The crash remains under investigation, troopers said.