I'm going to add gear oil to my transfer case today. after repairing a inspection plate leak. I came across this gear oil from Super S, called supersyn 100% full synthetic SAE 75w-90 gear oil and want to make sure this will be good to use in the transfer case. On the bottle it says use wherever API GL-5 /MT-1 is recommended. Anyone ever use this in there land rover our what your opinion on this gear oil?