Fine bronze dust in diff oil

[Ian Williams]

I think it is a design flaw, the spacer is a machined from mild steel and sandwiched between the hardened ground thrust bearings and retaining nut, it has to deal with some very high forces and shock loads. My personal view is that the minute machining ridges left from the manufacture of the spacer quickly compress, couple that with any give in the retaining nut thread and you introduce a tiny amount of clearance. Once this situation exists,, as Parazine says, the spacer wears, and this wear accelerates the more the clearance increases. I have tried making hardened spacers to see if that helps, the trouble is I have not had any axle come back to me after a high mileage so I can have a look.