oil in radiator res

That's exactly right! "Cascade" is the brand that we always used and it worked like you say....Good Call!

 

Oil pressure is greater than coolant pressure while engine is running.If the oil level is low (you said small black dot on stick) then oil is being pump into the cooling system tmhrough the oil cooler. This is the most common failure. Replace the cooler and flush the cooling system with Cascade powder.The cooler is behind the water pump under the turbo.When finished make sure the DCA level is correct. I dont believe you have any other type of failure due to still having pressure in the cooling system the next day. Sounds to me like classic oil cooler failure.

 

Check to see if the trans cooler is leaking, when we get oil in the coolant this is the most common source. (check the cheap things first)

 

just mix it in a 5 gal pail first with hot water, then add to rad.

 

You may have to flush several times. Ensure you allow engine to get upto operating temperature to open t-stats and flush system. Don't stop until you get clear water running out of radiator drain hole.