We have an Xplorer 230 XLW with rear bed. It has a tendency to wander on the road. I have attributed that to the 6' overhang past the rear axle, which moves the center of gravity too far back. Is t...
I had a Ford based van on a chassis similar to yours that was difficult to handle. I installed wheel spacers, had the alignment checked and upgraded the tires to Michelin LT's from the OEM Hankooks. The tires were the biggest help.
It is never going to drive like a car. I now have a B+ with dual rear wheels. It is more stable than our old van but still doesn't handle like a car. My suggestion is just to slow down. Good luck wth your RV.