Why get a new one? If you are not into serious wheeling then you are just throwing money away IMO. Rebuilt your existing one.

 

I just found out the previous owner replaced the u-joints,I don't go off-road(well, haven't gone yet I think I am afraid I will like it too much,lol).
I've only had the truck for two weeks and it drives great(It replaced my '06 Nissan Titan and it drives just as good if not better).Do you guys think with the u joints replaced I will be ok for a while.

 

Grease each u joint when you change oil. Make sure you get grease coming out at each cap, and do the slip joints as well.