Sources in Detroit have said for months now that Ford will follow the aluminum-bodied F-150, due late this year, with aluminum F-250s and F-350s.
Last week, a spy photographer working for KGP Photography said he has proof that the Super Dutys will be aluminum -- thanks to a simple magnet.
Photographer Brian Williams was prepared when an F-350 prototype arrived at a testing area in Colorado. He held a magnet against the bed's bare metal. No attraction.
Glenn Paulina of KGP said: "If they're using aluminum here, in the key punishment-point of a heavy-duty work truck, it stands to reason that aluminum is being used throughout the rest of the Super Duty prototypes -- just as they have on the 2015 Ford F-150."