short bed - sliding hitch vs sidewinder?

Learjet wrote:

N-Trouble wrote:

sfpcservice wrote:
The sidewinder in my opinion turns your truck back into a bumper pull by moving the pivot point behid the rear axle.

No, moving the pivot point back doesn't affect how the load is distributed. Weight is still over the TV axles so its still going to tow like any other 5er in that regard.

How does the physics of this really work?

yes the weight is still over the axle, but an arm is locked to hitch that extends reward.

So, any side, load such a semi pushing on the side of trailer would generate leverage on this arm...thus twisting around the hitch. So yes similar to a bumper pull...but with a shorter arm.

I haven't seen one of these up close and in person yet. the youtube videos show a "wedge thingy" that prevents the arm from rotating at the kingpin. The "turret" on the sidewinder pivots. This means a side load on the camper can create a small angle between the camper and the truck. That would apply a twisting force around the z axis of the truck at the king pin. Essentially trying to twist the truck around the kingpin.

So the forces are ALL still applied to the truck AT the kingpin. In the case of a side load on the trailer, the force applied at the kingpin would change from a purely side to side load at the kingpin, to a twisting force or torque. Either way, all of it is applied at the kingpin (which would normally be near the axle of the truck).

Whether changing that force from a translational one to a twisting moment at the kingpin is a "bad thing", I couldn't say.