The ring is more than likely the oil drain washer. I do my oil changes with the same oil. On my last change, I installed a fumoto valve so I should never need to change the washer. The price per quart seems way too high, especially since the dealer probably buys by the 55 gallon drum. The cheapest I have purchased is around 4.50 per quart. I wish Mobil 1 would sell in larger containers. The last time I called Mobil, they only sold in quart and 55 gallon drum.