I would have a few questions on this one:

How many times was the bypass filter and full flow filter changed during this time? Should have been done at least twice and the makeup oil should have maintained the additive package.

Why the heck would you do this without doing a few oil analyses along the way?

I saw a destructive test on an Amsoil bypass filter and it wasn't the best design. Gulf Coast, Oilguard, etc. may have had better results?

RT

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