I would check and be sure everything is perfect because I know that the 95-96 transfer cases and trannys were different from 97-99. You couldn't mix and match the two. You could put a 95-96 tranny in a 97-99 but you would also need to swap the transfer case....
well just read this:
http://66.193.230.60/~dlara/sedsmorg/showt...?threadid=13299
I don't know if any of this would have anything to do with the rear diff but considering that this is what it hooks up to I would think that the ratios may be different.
I am be completely wrong on this but I am just throwing out a suggestion to look into.