HIHUMMER, I had a vehicle swap with my dealer and it was a breeze. I had a bad rear diff, TCCM module 4 times and rear locker replacment twice.
It seems that GM Hummer WILL NOT LET YOU LEMON LAW a vehicle theses days. They do not want the negative press. (cant blame them) IF your dealer is reputable and wants to make sure it goes smooth a new H3 should be in your hands in less than a week. (in my case it was 4 days).