After reading I think that a "spindle drive" is little easier to do. And thinking of using a threaded pole with a geared small motor. Have anyone in here done this and can share some good tips on how to do it the best way. And if you have done this show some pictures and tell how you did it. I have only seen it done on Tamiya 1/14 trucks. If there is threads on this forum that explains this, can you post a link to that thread here.
I am not sure if I know what you mean. Do you want the Trailer to tilt like the carson model or do you want to take off a container like it's showed in this forum? In my opinion it would be very difficult or even impossible to have both possibilities: tilting like this truck and taking off an on like your examples.
Essentially both ways in particular are similar: you could take a threaded pole as the forcer (I hope this is the right word) and fix a screw nut on the cylinder. When the pole rotates, it will drive out or in the forcer. But I see a problem there that might be the reason for Sven to use a wire: where do you want to hide the gear for the rotate funktion? I think simybrigy is also using a wire, at 3:13 in this video you hear the model work for a second or two without any action, then probably simybrigy stops and runs the motor in the other direction and after a moment the model starts to move. I hope I could help you or at least start the "helping process".
Good luck for this project! It would be interesting to see how your truck developes, maybe you could show pictures like in your other thread. By the way, the Biokraftstoff-truck looks good, do you want to finish it some day?