Well now that someone finally said that, Olive oil is really a pretty good lubricant and works well in modern machinery overall. The two big problems is that being organic it tends to go rancid and like most natural oils, tends to have a poor viscosity / temperature curve. A better oil that is still natural is the oil of the castor bean, which is one of the very few, if not the only, oil to actually get thicker at extremely high temperatures. It is also one of the few decent lubricating oils that is miscible with alcohol.
Castor oil was the oil of choice in early Rhone or gnome type radial (rotary) engines as they were a contestant- loss type and the pilot of the plane ended up consuming a lot of oil from the exhaust. And yes, the pilots did suffer from the result of ingesting too much castor oil.... maybe Herr von Richthofen might have been called the 'Brown Baron' if not for the catchy color of his plane?
This has got to be a new low even for an oil thread.
Brian
Obviously I was kidding. Most oil threads are full of hooey; I thought I would add some.
I've used Rotella 15/40 in my last 3 rides without a single issue (100K+ total miles). I always replace the oil and filter every ~3K miles. If you want to spend ~$10 a quart on special "formulated" oil, go right ahead. I will continue to change mine every 3K miles at ~$13 a gallon.
Oh yeah, I also use cheap Napa filters... <gasp>
