Most bike racks come with a blurb in the literature that they are not certified to be used on the back of a trailer. Most likely due to all the bouncing around.
Swagman is one of the few that does not say this. We have an older version of
this one that's taken quite a beating over the years. I have never used it on the back of a trailer though so I can't comment on that. But we've had it for something like 10 years now. I've read posts here and on Jayco's forums that it works fine on the backs of trailers.
