Quote Originally Posted by Fluffle-Valve View Post
What is stopping the trucks rolling backwards?
there is a fixed or in the cases of drive through platforms a hydraulicly operated back stop that the back of the trailer rests against. In most cases a pair of safety chains are attached somewhere near the front of the truck as well.
complete cycle times vary widely from manufacture to manufacture. Some platforms require the tractor to be disconnected from the trailer and those platforms are only about the length of a standard grain trailer these generally cycle faster than the ones that the whole tractor and trailer are raised but the extra time is used up in disconnecting and reconnecting but there is a huge energy savings in not having to raise the added weight of the power unit and longer platform