I just looked up my build sheet and realized just how lucky I got with my purchase of a 02 Sahara last month for $1k with a cracked head. It has a Dana 44 w/ Trac-Lok! But the build sheet says it has a "5-Speed HD Manual Transmission. " Am I correct in assuming this is the NV3550? At any rate, this changes everything! 33s and Aussie (or Spartan) locker in the Dana 30, and I'll be set!