My dad has 30X9.5s on his stock '96 4.0. No rubbing but he doesn't wheel it hard.
I've got 31X10.5s on my '93 5.2 with the Upcounry package(factory 1" lift). They rub on the lower control arms at full turn. Not sure about offroad as I havn't taken it offroad yet, tires are toast.
Both are running stock rims.