broke my 4x4

[lhsnbsaoa]

last week, i went out mudding with some friends and didnt have any problem, used my 4x4 (used it pretty hard in reverse too). the next day while in 2wd pulling out of work, i heard what sounded like a gear grinding and it felt like my tranny downshifted and slowed my truck. i restarted it and never had that problem again, but now my 4x4 wont turn on. any ideas?