No. Look at actual size, not advertised size.
A 31x10.5r15 BFG Mud measures about 30.8x10.5x15 when mounted on a 15x8.5" wheel. Which means if you mount it on a different width wheel the actual tire section width will be different. A 31x10.5r15 SSR will measure about 31.5x10.5x15 on a 15-8 wheel. That difference on a small truck or a vehicle with little tire clearance can be the difference between tons-o-rub and no rub.
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