Bob Chaparro asked:
"Identity Of This Car? (Undated)
A photo from the Detroit Public Library:
Click and hold to enlarge photo.
View of the trailer of a Yellow Truck and Coach truck for the T.M.E.R. & L. Co. being loaded into a railroad freight car. Handwritten on back: 'Yellow Truck & Coach.'"
TMER&L Co. = The Milwaukee Electric Railway & Light Company.
The North Shore (CNS&M) and South Shore (CSS&SB) were early offerors of piggyback service in the 1930s, so TMER&L experiments with intermodal isn't surprising, but this photo does raise more questions on this particular experiment.