I've pulled out one or two leaky drain plugs withouy losing much oil. On the most recent one, whomever changed the oil decided to omit the gasket on a Toyota engined Pontiac. I left the dipstick and drain plug in and and made sure that the engine was cold (like 20 degree sitting outside cold). Only a few ounces dribbled out while I was adding in the missing piece. Dipstick indicated level barely changed before vs after.
