I'm looking @ a 2004 Polaris Ranger 500 4X4.  The owner says it needs a new transmission.  From what I have gathered the Rangers have a gearcase, not a transmission, correct me if I'm wrong.  Different word, same result forward and backward.  I have all kinds of experience with working on cars, trucks, everything from replacing engines, trannys, to body work.  If I can work a good deal on this UTV how hard would it be to put in a gearcase, or is there more to make this UTV move than the gearcase??  Something to tackle, or stay away from??  The current owner advises the motor runs great.  My question is what kind of torture was this UTV exposed to  for the gearcase to fail??  What else should I look for??  Thanks for any advice.