Mobil 1 has a new blend of synthetic oil that is guaranteed to last 1 year/20k miles.

I drive my 2013 Subuaru Forester about 18k per year. I am due for an oil change in about a month or so. I am putting the Mobil 1 Annual Protection in it, along with a Mobil 1 filter ... and I am not going to change it for a year! Ha!

Now, I have one of those "two-stroke" Subarus, that likes mixed drinks, about 1 quart of oil every 3000 miles along with gasoline. So, by the time I hit 18,000 miles in Feb-March 2020, I will have added 6 quarts anyway.

I am contemplating a used oil analysis after conducting this experiment. It will be interesting to see how it turns out!