This is a quick how-to for changing your own rear differential oil. this will save you about $40 or so from taking it to a shop. 1)loosen bolts (dont remove) all around diff cover and allow fluid to drain. 2)after done draining, remove diff cover and set off to side. 3)inspect gears for chipped teeth and look in carriage for debris. clean anything out that doesnt belong. 4)replace new gasket or use RTV (black) and put cover back on. NOTE: if you are using RTV to create a gasket then wait 1hr after putting cover on to let dry. 5)find fill plug and open (should just require 3/8 ratchet, no socket needed, and maybe 3" extension). 6)Fill using owner's manual preferred oil. Trust me, its in there. FOR 01 EXPY WITH 9.75 REAR....75W140 FULL SYNTHETIC WITH OIL FRICTION MODIFIER...JUST OVER 3QTS. And there you have it. It just cost you $75 and about 1hr (drain time, wait time on RTV, and fill time) to do the same job that most places charge $110+tax. I will have some pics to follow.