This truck is described on some sites as a beer truck from 1937 but I doubt it because no advertisement for any beer make is shown.
I found this truck some time ago, described as a Ford from 1936 with a license plate D13-900 (I can't decipher from which state : Illinois ?). On the side of this truck, there is a four-word inscription : the second three-letter word coul be MEX or NEW; the third seven-letter word could be PRODUCE and the last word seems to be OHIO. Under this inscription, there is another three-word inscription in small letters, and under this one another unreadable inscription in smaller letters. Maybe it was a demonstration shop for some product