As mentioned above, you don't need to go to an RV dealer for tires--you should go to a TIRE dealer. Also, be careful of the tire origin--many Chinese tires seem to blow early and often.
Also suggest that you put the highest load range on that will fit under the wheel wells without changing out the wheels. If you have "Ds" go up to "Es"--your life will be less stressful.
2016 Tiffin 40 QBH
2015 38RSSA, traded
2005 TK3 #1869, 10 yrs of memories,
2017 F450 KR--one more Ford is it
2009 F450 4x4-died; 2010 F450-retired