Changed my Tcase (NP205) fluid to Royal Purple 75-90 syn before going to Baja last weekend. After about 60 miles total with the case engaged (10 4lo 50 4hi) I started to feel/hear binding and could smell the fluid, back into 2hi on highway I had no further trouble. Should I have used motor oil? 205 is a gear drive box, gear lube is what should work best...Right? (did i just burn up my Tcase...) Anyone have guidance/experience on this?