The Scott County Coroner's Office said Tuesday the man may be 44-year-old Trent Burnett, although investigators were not able to say for certain.
Burnett is a maintenance worker who has had eight brain surgeries, family members said. They said they thought the surgeries may have affected his memory.
The truck and the body were found Monday on an old logging road in a wooded area.
The body was badly decomposed and may have been in the truck for months, Coroner Joseph Crimm said.