[elmariachi]

Torsions are essentially like independent rear suspension. Each of the wheels can move up and down on their own without affecting the other wheel. With torsions, the spring action and cushioning happens behind the spindle and in the end of the axle and is less likely to be transmitted up into the frame assembly. On the other hand with sprung axles, the spring is attached to the frame and so every bump you hit gets transmitted directly into the frame and entire trailer. Torsions can also allow for a lower ride height, which lowers the center of gravity for the trailer but more importantly can make the approach for a Cobra shallower and much less likely to conflict with the door hinge area.