Rough riding F53 chasis.

Weigh your rig and set PSI on the tires accordingly. Mine was way over for the weight and rode like a brick. Set the PSI correctly and it really softened things up. As far as sway you can do the CHF in your driveway for free and that eliminates most of the body roll. Both of those options usually solve a lot of the ride quality with no expense whatsoever. After that if you still want to have it ride better, then I would look at shocks. All that said, the F53 is notoriously rough, especially with less than pristine road conditions. That chassis is used for a lot of purposes, mostly commercial. I think MH's are the only consumer application.