Originally Posted by big gear head
It's possible that the oil had some type of graphite added to it, or maybe some other additive that made it look like that. I don't know what is in the Auburn oil additive. That might be what it is. I'd let it go for now and see how it holds up. If it still makes the noise then drain it and start over with new oil and 2 bottles of GM or Ford additive.
If you ever decide to do this again, Eaton makes a very good Posi for that rear end. I highly recommend it over the Auburn.
I had the pumpkin put together for me but I installed it and put the oil and Auburn additive in it. So if there was any graphite, It would have had to been assembly lube. But, I don't remember if there were any lube on the internal parts on the pumpkin before I put it in. However, as I remember, the Auburn additive had no color to it.
I'll let it go like you suggest then.
What do you think of a magnetic fill plug idea? Seems like a magnetic drain plug would be better but I don't have that option.
I sure thank you for helping me on this. I saw your profile on another forum that you own a rear end business. Nothing like getting advice from a pro. It's nice of you to do that.