Re: Alpha one oudrive oil.
It usually takes me about 1 and 1/3 quarts.. you need to drain the old fluid by removing both the drain screw at the bottom and the vent screw at the top. Then you hook up the pump to the drain hole in the bottom and to your quart of lube and pump the fluid in from the bottom until you see it coming out of the vent hole at the top.
Also make sure you use new drain screw gaskets. I just replaced the gear lube and it leaked out because the drain screw gasket was bad. Only a $20 mistake, but still annoying to have to do it again. Gaskets cost like 75 cents for a set of 2.