Machines

[Diaphone Jim]

Always change filter with contents joining drained oil in pan. (Except the 1/2 ounce or so that Nissan designed to get away to drip on floor. Always parked inside on same place on concrete.)
100,000 miles on engine, always full on dipstick, no add necessary between changes.
Baseline is the same: drain 'til no drip, start with 3 5/8 qts.
3000 to 4000 miles later the 1/2 quart or more is gone.

But keep in mind, I get the same mystery with other vehicles.

Grav: Try me with the bad possibilities.