I have the Discovery Trailer by USA Trailer Store. I like it but it always rode a bit hard and noticed it even more going through the tunnels at Zion. Man it was noisy and bounced. I just installed some Monroe Max Air Shocks. Pretty easy to install and air hoses were easy. I did air them up and no leaks.
When I had weight in the trailer with the old shocks, it cambered out and looked strange, but did not wear the tires out on any given side. The air shocks should solve that and ride true with weight in the trailer. Very little air in it now and no weight, looks high, but push down on the back like there was weight in it, and it is smooth. Hoping this will make it an awesome smooth pull.