Hello, I think I have a bent axle on my dual axle trailer because on the rear tires, the insides are wearing faster than the outsides. So I've been calling a few places locally to get it done and ...
Very simple job if you're mechanically inclined and have the tools. Yes, you unbolt the axle and bolt a new one in.
Remember to replace your u-bolts with new ones as they're not supposed to be re-used. Now is a good time to upgrade to wet bolts, bronze bushings, etc, but that's a discussion for another day.