The guy I bought my truck off of had a 9second nova. He showed me pictures of the thing doing 4 foot wheel stands. I asked him about the rear and he said it was a 12bolt. From the stories he told me they hold up to a beating.
I was actually quite suprised because tire size wise they are quite week for an offroading truck.
If you NEVER EVER EVER EVER want to worry about breaking anything get a full floating 14 bolt. Thats what us mudders use for strength

500lb's of strength.