Are you running the factory or an aftermarket damper?
No, that's definitely not the problem. I'm running 37's and they're fine on the road. It might be a little stiff offroad if I'm trying to turn and my wheel is against something or my front is locked and I try to turn.
You mean returns slowly back to straight? That could be your caster angle. What angle is your pinion at? Have you used lower front control arms on your Jeep to correct for any lift? This could definitely cause wandering or weird sensations.
Unless you're leaking power steering fluid or something looks broken, I doubt it's your steering box. Before you drop all that money, check your ball joints for looseness and all your steering connections - track bar links, drag bar link, etc. This could be giving you mild death wobble and you need to address this first. Definitely check your caster angle as well. If that's off, it will affect your ride.
Setting your Caster Angle