Whooa! That's a pretty big contraption!! So something must extend inside the track and hook the walking beam axel. Mr. Bombardier sure thought out of the box. I bet it works good. I know towing meat wagon trailer works fine from a pindle mounted on the back of the tub. But they arn't 4000lbs. So looks like one came with your machine Akimp? What else came with it? It may be just the angle or the photo but it looks like your rear tires are angled in at the top. My J5 was like that and it was due to bad walking beam bearings.