I have tried several different bumper mounts on my 5th wheel. The first was a two bike carrier with the 1.5 " hitch , and the bouncing caused that to bend out. I replaced that with a 2" model, and it hung out too far from the bumper, so I modified it to shorten the distance from the bumper. I just inspected the unit, we have been on the road for two months, and found the bumper has cracked at the weld from the bouncing. The bikes and racks are 20 lbs under the manufacturers max weigh for the bumper.
I am now in the Keys and having to get a mobile welder to come and re-Inforce the bumper. He is recommending that I have a hitch either welded or bolted to the frame., as a permanent solution.
I Originally was going to do that, but the manufacturer advised that doing so would void the Frame warranty, which is one year. That year ended this month, so that is the plan when I return home.
