turnin' wrenches
To be employed in the automotive / diesel industry.
"Back when I was turnin' wrenches, I worked with this guy who drank Coors Lights and fought with his old lady all day every day."
turnin wrenches
To do manual labor, Manning up and working
“You gotta man up one day and learn yourself so get your ass over here Jody and start turnin wrenches”