Here are two flat cars with tractor trailer loads. I bought these separately and would not conclude that they came this way. One of the flat cars is a NYC and I suspect it should have a NYC truck, but that is not to say that's the only way the NYC flat car came!
These trucks could be a collection in themselves. They came in Burlington, NYC, Walgreen, Allstate, Western Auto, Sears and Wards. Some of these trailers came in more than one color, some have door variations, some have more than one type of logo and some have wheel variations. I have seen the cabs for these trucks in black, red, blue and gray. The Sears cab can be found with or without the logo on the door.

This Burlington trailer is a rare variation that has the logo rubber stamped on the sides in the area embossed for the nameplates. As you can see the slots for attaching the nameplates are there but unused. Are any other road names rubber stamped?
If you have a rubber stamped trailer other than Burlington email me at marxtin@comcast.net.