I have a 2004 Tacoma V6 Prerunner that has the TRD package. It has the rear differential lock on it, but I am looking for more. Is it possible to change a 2wd to a 4wd? What would it take and how much would it cost? I am trying to figure out which would be cheaper to do. I can sell my current Tacoma and buy a 4x4, or make my current truck(which I love) a 4x4. Let me know!