I have the 4000 lb axle (thanks for telling me how!). I was lubing joints down there and wondered about oil for the power steering gearbox. Does the power steering fluid lube the box or is there a separate chamber outside the pump circuit that needs gear oil or something like that? The van has 244k miles so if there is oil I should probably change it. I searched the forum but I'm guessing the vans have a different steering gearbox than the trucks, is that right? Didn't find anything in the van section.