I don't know if this a silly question or not, but just thinking about it, how much would it cost or has anyone done it, made their 2wd a 4x4 can it be done or does it cost to much, would i be better off buying a 4x4 xterra. please respond before tomorrow.

It would eb A LOT cheaper and better to buy a 4x4 then to try to convert a 4x2 to a 4x4 if it can be done.