Hi John,
Welcome to this forum and thanks for your interesting picture plus story.
Yes, the truck in your picture is a Dodge D60, or more correctly, a Dodge D60L 60-cwt GS (General Service) truck. The picture below shows the same type of truck, although with a different kind of cargo body (wood, the one on your father´s truck is steel).
Please tell us more about your father!
Thanks,
Hanno
P.S.: sorry, my posting crossed Pete´s