Okay here is the ACTUAL correct answer to that. Me being a dispatcher if I see that a customer is not covering a 53' tractor load, then I will give them a call. I will ask them what the freight is. Okay so they say it is like 30 pcs. 48x45x46 500 lbs. ea. Well I will tell them I can send 2 filler straight trucks. This means they are aware that I am simply sending whatever size straight trucks down there I can get, and they just fill 'em up. No requirements just dock high straight. Now, if it were like 8 pcs 30000 lbs. 290x45x48 or some craziness like that then no you cannot because it simply would not fit. This is the correct answer. Its not about the size of the truck, its about the size of the freight, and if it can be fractionalized that way. Now, If your customer does not know that you are sending 2 straight trucks instead of a 53' trailer, then you got a problem if they were trying to "fill" the truck with whatever they could. Even if you thought it was going to be only 18 skids, If they add more, and then they wont fit on your trucks, they are going to be asking why 20 skids wont fit on your tractor.