I think 245/75R17s on my stock rims will fit without scraping anything. That's a 31.5" tire. There's a pinch weld on the back of the front wheel well that has to be bent over, and maybe some massaging of the inner liner near the front. I've been told the rear wheel wells are not a problem.
Those tires will be (probably) Goodyear Duratracs studded and used in the Winter only. I don't venture far from home because of lung disease, so I don't travel freeways much except when going to the VA in Reno - and their roads are almost as icy as where I live. When Spring and Summer roll around, I hope to have some 16x8 Vision 398s...

Mounted with 245/75R16 tires that will be suitable for the kind of wheeling I enjoy and still be okay for the occasional trip to Reno, even in the rain, but won't necessarily be much good for icy road conditions.