I dont know of any that are better for high heat...
I have heard that the redline shockproof 140W-250 works well for the tcase heat...one member who used it parked his truck on a side hill so the passenger side was low and the fill plug on the tcase was on the high side...then he stuffed it as full of lube as he could get.
I realize that overfills the case by quite a bit but he swore it worked very well.
Lord send your Holy Ghost into our hearts and make the desire of our hearts Your Will.
Pro-choice, that's a LIE, babies don't choose to die!!