Some add-ons allow you to hual one giant piece of cargo or several smaller items like bricks or similar up to 6 at once. 

I have not played the game  in a while and was looking at some ideas and well quite frankly cargo hauling needs improving dramatically.

Let"s say you are hauling a massive pipe or even the Rocket from the Amur Region of the Russian Federation, and you want to take the FEM 37 and you can and one giant pipe wile fit in the bed . The cargo will be securely anchored to the bed and will remain semi-permanent in place ,even if you manage to tip the vehicle ! Once you unload you can freely move the cargo  to where you need to.

Well there are already mods for this BUT,  THERE REALLY AREN'T MUCH OPTIONS FOR THE VANILLA GAME ITSELF. THIS NEEDS TO CHANGE.  I included  LINK TO A SITE THAT KIND OF EXPLAINS THE TERMINOLOGY of the word. 

The Vanilla game needs more options for ALL VEHICLES for hauling cargo and cargo slots

What Does Vanilla Mean in Gaming?