not factory at all, the bumper itself isn't anything like a 38-40 bumper - looks more like something that would have been on a firetruck by the aftermarket body maker
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics