Schaeffers make some excellent gear lube for transfer cases and drag race rear ends
The only problem I know of with the drag race gear oil it is 250 Wt. Which means you need run the car on jack stands for 2 to 5 minutes to warm it up before pulling into the lanes to race
My Son in Law use to work for a ski resort in SO CA maintaining all their track vehicles, they used Shaeffer brand lubes only in all of their vehicles from the general managers SUV to all the big snow cats, he was amazed that none of their lubes would not mix with the water(from condensation) in the snow cat transfer cases or engine oil, the water would drain out first and then the oil or lube would follow
I wish I knew of a west coast distributor that I could buy their products from up here in central Oregon