75-90 Mobil 1. Replaced after 15-20k miles and it was like new

 

So here is my oil report a year later. About as many miles as the castrol syntrax but not near the contamination. In fact, I had nothing on my magnet and the fluid came out clear. As I stated, I'm not sure my diff fluid had ever been changed before I used the castrol, so maybe it was cleaning my diff. I dont know. But I am sticking with amsoil from now on after seeing this report.

 

That should be reassuring. Good to see wear numbers trending much lower. Thanks for posting the data