Mobil One is Dino oil and just like all dino oil about five years.
I had a bottle of "synthetic" or dino oil from a Auto parts store. the one with the red star on black. It was several years old, perhaps ten.
I poured it into my pickup when the level was low. I always use Mobile One but it makes no difference. About half way or better out here comes a slug, ofoil or grease or whatever, darker in color. I warmed the truck up good and drove it a ways and got the oil changed.
Shelf life of real Synthetic, I dunno and still ahven't gotten around to buying it and installing it in our vehicles, even though someone here gave me a link to a source, some time ago.
