I would be checking with your insurance company before you buy anything.
You have modified the unit out of stock. I live in the Mountains of BC and see raised vehicles with big troubles all the time. It is not so much the expected problems that will hurt you you will learn quickly to break early for corners. What will hurt you is when you are 1/2 way threw a corner and you have to break hard, or make a quick evasive move.
Oversized tires can put a lot of strain on brakes, transmissions, and it raises your gear ratio. It your RV is much heavier than 10,000 lbs, I can see you having some serious issues with braking and transmissions it they're stock.
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