Out of curiosity, I checked the Lionel site to see what is included with the single car. It does not appear to have the truck assembly without couplers included.
From the Lionel site for your car:
Expand your intermodal layout with these new enclosed autoracks! Sized right for smaller layouts, these cars capture the look of these popular large modern prototypes in a model that can go places our scale cars can't.
Die-cast metal trucks and operating couplers
Two removable containers per car
Rail Line: CSX
Gauge: O Gauge
Scale Type: Traditional
Brand: Lionel Trains
Min Curve: O31