Tony year to me appears to be 1932 - 1935. Thought they were Fords for a moment but the rear hinged cab doors have thrown me off that track.
They could be Dodge's as Dodge trucks had the name plate on the side of the bonnet similar to those vehicles and the US Army used a lot of Dodge trucks in this size range up until the war.
cheers
Cliff
EDIT. it is a 1934 one ton Dodge in my opinion after doing a little research. The giveaway is the way the doors are hung as only Dodge was using the 'suicide doors' at that stage. Ford, Chev international etc were all front hung doors.