I just wanted to say thanks for posting all these old Case IH videos, even these more mundane ones are an interesting look into the past. My guess is that these are early magnum transmissions based on the Case branded filters and serial number tag. The magnum transmissions were built at the transmission plant in Sturtevant (a suburb of Racine, now the home of the complete tractor plant) and moved to downtown Racine to be assembled into tractors. That would explain why they would be worried about cramming as many of them into a trailer as possible.