I recently bought a Ollie EII. As delivered and loaded it weighs about 6200lb. I also bought a Trax6000 to move it around back of the garage on concrete with a rain slope only. I've been using the Trax on the Ollie for about a month now and it will do the job, however, the Trax is just about maxed out. To handle the much larger momentum of the triler I've learned that the light weight Trax has to move slowly and be sure to use the brake . Sometimes when trying to turn the trailer too sharply the resistance of the tandem axel to turns is too much for the Trax and it will have a tendency to tip sideways. Just don't take too big a bite at once and your OK. GO SLOW!! I installed the longer handle and that made the system more manageable when trying to redirect the trailer. The Bulldog coupler requires the Trax supplied shim for the ball mount to clear the slide collar. Be sure to cinch up the cam over lever as tight as you can make it. This will add stability as well.