http://www.forestriverinc.com/nd/def...source=summary
Dry hitch for RK version is 1515 pounds and the RL version is 1200
The GVWR for the RK version is only 8778 while the RL version is 9144.
Look at the slide locations. The RL has TWO slides aft of the CG while the RK version has one large slide with half over the main wheels.
The moment arm for the heavy slide aft configuration in the RL version moves the king pin weight off the king pin. That is not the case in the RK version. That weight stays on the king pin.