Those of you using synthetic diff lube, what are you paying for it where you live? Mobil 1 is about 7$ a quart here and amsoil is about 10$ a quart. The owner's manual says my Dana 80 takes 6. 8 pts. That doesn't seem like much for such a large diff. I can't imagine it only taking 3 - 4 quarts to fill it up.
Travis
Travis