[12Ounce]

You can be sure that you are also getting coolant into the oil ... to make sure, grab an oil sample and send it off to Blackstone labs. Don't expect to "see" the coolant in the oil ... that would require a huge coolant-in-oil quantity. A little coolant in oil does a lot of damage.

Oil in coolant is mostly just a mess, not doing a lot of damage.

There is at least one crossover leak ... possibly in the head gasket or the lower intake gasket. I vote for the lower intake gasket if the engine seems to run well.

The leak passes oil into coolant when the engine runs and the oil pressure is high ... coolant pressure is usually around 16 psi ... oil pressure can be 60 psi or higher. Oil wins this tug of war.

When the hot engine is shut down, the leak changes direction. The oil pressure is at zero ... the coolant stays at 16 psi, or less, until the coolant cools. The coolant wins this battle and goes into the crankcase.