Wear metals in VOAs?

[sunfire]

My first post, but long time viewer. BITOG has made my 05 Corolla run smoother, faster, more fuel efficient than ever. But having looked at a lot of VOAs (settled on PP for my Corolla) I've noticed small amounts of wear metals (Al, Fe).

https://bobistheoilguy.com/forums/threads/mobil-1-5w30-castrol-gtx-5w30-pen-plat-5w20.75582/

Blackstone seems to think the wear metals are from the oil distribution:

https://bobistheoilguy.com/forums/threads/royal-purple-10-40w.79502/
https://bobistheoilguy.com/forums/threads/royal-purple-10-40w.79502/

Although, just about every other VOA contains some small amounts of wear metals. Does anyone have any ideas where these wear metals are coming from? Could they be additives like copper in some oils?

 

[Dad2leia]

Not to over simplify the answers, but yes to all.

Aging lines contribute to wear metals. Natural wear contributes to wear metals. And some oil additive packages show up as wear metals to start.

 

[sunfire]

My only concern is that the wear metals could possibly come from used then recycled motor oil. Somehow the wear metals were not fully removed from the new oil.

 

[shanneba]

The iron/Aluminum could come from the pipes used during production, bottling or transporting the oil. 55 gallon drums could contribute here.