Set up page onload event.
Every differential has a breather.
It is usually just a vent to the outside air, covered by a cap that helps keep debris out. It is there to equalize the pressure in the axle as the temperature within the axle changes. Without a breather, or if your breather is clogged, the pressure that builds up inside the axle housing will most likely push gear oil past your pinion or axle seals. The stock breathers have no way of keeping water out of your differential case if you submerge the axle. This pulls whatever is on the other end of your diff.