The suspension on my 2015 Nash 22H needed to be completely replaced. The equalizers were cracked, the shackle bolt holes were oval, the spring bushings were worn out, the bolts showed wear patterns...
Most trailers use this type of suspension, no matter how much you paid for it. Most trailers are towed to the local campground a few times a year and the manufacturers build accordingly.
If you actually want to use a travel trailer to travel, you need to do some upgrades. I replaced the junk springs, plastic spring bushings, weak axles and shackles.