Final assembly was at GM-EMD's La Grange, Illinois plant.

The F9 was also built in Canada by General Motors Diesel at their London, Ontario plant.

The F9 was the fifth model in GM-EMD's highly successful "F" series of cab unit diesel locomotives.

The F9 used a 16-cylinder 567C series Diesel engine developing 1,750 hp (1.30 MW) at 800 rpm.

[1] [2] An F9 can be distinguished reliably from a late F7 only by the addition of an extra filter grille ahead of the front porthole on the side panels on A units.