Amsoil application guide shows to use 75W-90 "Synthetic Manual Transmission and Transaxle Gear Lube" for GL-4 rating or 75W-90 Severe Gear Lube for GL-5 in the transfer case. Since I am already ordering 75W-90 syn for the diffs, I would like to use the same in the Transfer case. Anyone know the difference? I sent an email to Amsoil, but have not heard back. I can't bring myself to eat the price difference between the regular gear lube and the severe.
What do you use?
What do you use?
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