mike-s wrote:
As long as you stayed within the rated capacities....
Even though the OP says he was under the 3500 lb tow limit, I'll bet a Costco Dog that he was over the 350 lb tongue weight limit as stated in the owners's manual. We don't know for sure if the trailing arms are damaged or just the bushings are shot, but since the OP was noting irregular tire wear issues on the rear, I would say the TAs are bent somehow, probably from overloading.
Also the hitch was not OEM, it was installed aftermarket, so perhaps whoever installed the hitch did not attach it correctly and placed too much stress at the wrong points.