Who makes motorcraft spark plugs?

Ford.Ford doesn't actually make the Motorcraft spark plugs, Autolite(owned by Honeywell) makes them. So buying OEM style Autolites is the same as buying Motorcraft spark plugs

Actually... Motocraft is a priviately owned company. They used to own Autolite, but sold it off in the 70's. Two different companies. I also verified this by calling Autolite and asking them. 1800-890-2075 ext 1 then ext 3. Also see