I think that you are going to run into the same problems the rest of us have. If you want to run a larger than stock tire you will need a rear spacer between the rear duals at least. Some tires may require you to run a spacer on the inside dual between the inside dual and the mounting surface.
LT.
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2006 Dodge dually, QC, LB, 6 speed standard, Smarty, AFE stage II CAI, MBRP dual 4" exhaust, Quadzilla boost fooler, ATS Diesel intake manifold, 6" Superlift, 315/70/17 BFG AT's, South Bend Con FE clutch.