Hi, this would be a new special transport truck for the city theme. Like the new trucks it is 6 studs wide (7 for the trailer).
It is inspired by the fantastic old set 6335
"Indy car transport" , this could be a modern re-edition of that set, see them together in the last picture!
The old set was transporting three formula one cars, this set is made to hold five go-karts, that seems to me better considering the whole truck dimension.
As the old set, the trailer has hinged parts that allow you to charge and uncharge the karts.
In my opinion this would be, as the old one, a really playable set!
See other images at: