Torque Tube Design Explained
Let start by saying this is not our custom design, but it was our idea to use an already proven and effective design to address the issue with the Casita chassis. The torque tube design is commonly used by large gooseneck heavy haul trailers and has been for some time.
The torque tube is a round tube that runs front to back through the lateral crossmembers. It is welded to each crossmember tying the chassis together. The result greatly reduces, almost eliminates, the Casitas’ chassis from twisting. You will notice in the photo below, we laid out the crossmembers and torque tubes on the ground, separate from the chassis, to better illustrate what is going on. Notice there is a separation between the crossmembers in the center where there is no torque tube. This is where the grey water tank would be located. This prevents us from being able to run one continuous torque tube, forcing us to modify the design and fabricate it into two sections.