How many of us are there? Owners of Dodge based RV's?

Did you loose any performance in the hills with the taller tires, was pulling harder on motor or the same, I have figured that with the 215/85/16 tire I should go down about 125-160 rpm's at 60 mph, my currant rpm's are 3000 at 60 mph.
I will be going from a 16.5 tire at 28.45 inch tall to 16 tire at 29.9 inch tall and increasing a extra 3500lbs of safety over the 16.5.