gear case

i recently bought a brand new 2008 inchworm transfercase that has been sitting in storage all its life and i cant figure out the gear ratios, in high rear. low front in is 2.3 to 1, but in low rear. high front it is 4.7 to one which i know is proper but when i do low both it is 9.5 to one im not...

I always thought the differentials and gear cases (transfer excluded) were indestructible.. is it normal a 40 rear differential can get so much wear the teeth will break?