Depends on what kind of offroading again. Jeeps use a dana 28, a tooth pick for an axle. So if you are going anywhere where there are rocks and stuff, it could be ruff...
One more thing I thought of, does the 85 have a solid front rear axle?? The 77 does I'm pretty sure. Solid axles area always better. Which is where the jeep would be nice, unless you are going somewhere with rocks. I think the F-250 would use a Dana 60 or something? And the 150 maybe a 44? I can't remember the numbers... Arizzx would know.