I remember buying re-refined oil that was parrifin based. I would buy it by the gallon for my worn out 283 that burned several quarts every few days. Never had to change the oil.Pepboys used to sell "re-refined" motor oil under the name Capital. It was used motor oil skimmed off of settling tanks or ponds. It worked fine in used cars of the times, the ones that smoked and dripped.
Now I recall the parrafin base was called bulk oil, not re-refined, and it came in 2.5 gallon jugs. How primitive the old cars seem to us now, couldn't use crap like that for long now. Anyhow all my stuff arrived and I am sitting at 39,100. Just waiting to get the "git er done" part going.Paraffin base oils were made from Pennsylvania light crude. It actually looked like motor oil when it came out of the ground, only thicker. Gasoline was 25c/gallon.