Axle oil change

[WhtST]

If your differential fluid is contaminated at 6000 miles you’ve got issues

Every differential I've changed looks like mercury on the first change. That's a good thing, as the hypoid gears work harden there is debris generated. Resulting in contamination. Now if you are questioning the validity of the oil due to the contamination...I don't know. I do know cant be beneficial. Or maybe every differential I've encountered has impending catrostophic failure immediately after I sell it....maybe, don't know.

Like I said, cheap insurance.

If you don't want to change it don't.

 

[KNTRDR]

Fair to say a lot of factory-fill fluids look bad because of additives they contain for break-in management etc etc

 

[rjacobs]

additives they contain for break-in management etc etc

Old wives tail...or at least not applicable to modern vehicles.

Break in oil in factory fills of anything hasnt been a thing for at least 30 years(probably longer) that I am aware of. Machining tolerances and materials are so good now that traditional break in is "almost" not a thing anymore.