I checked my oil after I got home and found it was gone! Just a smudge on the end, under the low end, black, and smelling of gas. No coolant or milkshake.
If your oil is being thinned out with gasoline, then it could be
evaporating (which would make leaks harder to see)
being sucked up much more easily by the PCV
diluted to the point you're not seeing it being burned off when it sneaks past the rings or gets sucked up by the PCV
I'm not a slant-6 expert, but on the other engines if the fuel pump has a bad diaphragm it will leak fuel directly into the oil pan. Or the carb could just be pig rich and washing down the cylinders, which would also make the plugs black and disguise the burning of oil. Just an additional theory, not saying anyone else is off the mark.
