Scary Handling Problem

I have much the same problem that you have, my motorhome has a long rear overhang, a light front end which leads to my toad pushing the rear causing oversteer. I have mitigated the problem by replacing the shocks with bilsteins, adding hellwig sway bars and a blue ox track bar. My motor home has hellwig overload springs on the rear axle, stiffening them seems to help. I carry 60-65 psi in my front tires and 80psi in the rear. I had the front end aligned with more toe than specs. This makes the my motorhome handle ok, not as neutral as with out the toad, but not at all scary.

Mike