It’s definitely strong enough. Very durable. I use mine for my kayak and oztent. And anything that doesn’t fit in my car.
Not without a lift. Even with a lift I think they may rub in the wheel wheels. I assume you are retaining the stock rims and offset. Perhaps with the right rim and a tire with a tapered edge it could work without mods.
I'm no tire expert, but my 255-55r-19 tires with factory rims, look too be near max. A 31-10.5- 18 could fit.