just under 2 qts. we used mobil 1 synthetic 80w-90 i believe. sean can correct me if im wrong.

its super simple. there are 2 caps on the differential. simply take out the bottom 1 and give the fluid time to drain out. make sure you dont lose the washer on there. next replaced the drain, undo the top left cap. squirt in as much of the 2 qts until it overflows. let it sit and recap.