YEP, you need a bar…but on most of what i have experienced have a similar system, but you have to put the bar into the hole, and twist it to allow jacking, and twist it the opposite way, to lower the cab back down…however, the one pictures seems to have a different kind of bar socket being a hexagonal rather that a screwdriver type…ie the head of the screw is in the socket, and the end of the bar has a screw type bar that fits that…if you get my drift.