What you see in these photos was a Rhino what was subsequently retired (sold) and replaced with a can-am HD10 defender. If you care, its reviews can be read here. http://www.tractorbynet.com/forums/atvs-utility-vehicles/355357-can-am-2016-defender-hd10.html
The jack lift worked OK. We wish it went a tad higher and we also broke it once but wasn't to hard to repair. The walking beam mount pin remained 3/4 in size but what's not visible in the photos is the 4 locking collars we welded to the beams channels to lock the pins in position. The short pipes you see which got welded in to create the bearings, are dram tubing. Yes lots of messing around but by the end, the trailer was made much stronger or more durable. Not being able to weight the loads, we could have been moving 2500lbs.
Why was the Rhino sold, broke, wore out, and why replaced with a Can-Am UTV?
I have a 2012 Rhino, low miles so far, my biggest complaint is it goes to fast in low range, wish top speed in low was 5-10/hr.
I think your trailer is a lot better after you've fixed it....