I went back and checked and the owner has just put new cooper Discoverer tires on the unit.
Just a heads up here about matching tires and wheels so check to your satisfaction.
The Goodyear Fortera P_ tires were not a LT truck tire on Santees Domani but a P (passenger) that Domani was using. The tire has a load range of 2756 lbs @ 50 psi.
Now fed regs require a P tire when used on a trailer (or truck) to have its capacity derated by dividing by 1.1. In other words his 2756 lb tire is now rated at 2505 lbs which brings up a problem for Santee.
His particular Domani had 5200 lb axle which by fed regs require at a minimum a tire with 2600 lbs capacity. Those P tires simply didn't have enough capacity. Of course we all know some RV trailer mfg aren't up to speed on fed regs regarding this subject.
Now those big wide wheels which by the way aren't the best idea for a trailer with mid mounted axles that receive tremendous ply shear stress/bearing stress/spring hangers and especially the U bolts while they side scrub around corners. Thats one reason our trailers come with narrow tires and wheels like the LT 235/85-16 E or G or the 17.5" wheel and tire combo's.
You say the previous owner mounted Cooper Discoverer tires. looking on Coopers web shows 8 different Discoverer tire lines. One 20" Discoverer line shows a LT E which is a 80 psi tire at 3750 lbs capacity. If your Domani has those 10" x 20" wide wheels make sure their rated for 80 psi.
Sorry for so long reply but having made a living pulling heavy trailers commercially, I'm anal about safe tires on trailers....and my trucks.