LB7 Coolant in Oil, Help!

[dgalvin66]

Hello
I have an 02 GMC Sierra 2500HD 4x4 that is my daily driver. I have been driving it since early 2004.
It has just under 200k on it. Never overheated in the Las Vegas desert.
About a week ago there was a Low Coolant message on the dash, I topped it off and thought it was fine.
Yesterday I was checking all fluids and such and when I got to the Oil it there was grey gunk all over the dip stick and water in the oil.
There is NOT any oil in the coolant tank.
It is running fine and no smoke. I need help determining what the cause is. I am hoping it is not a head gasket and instead something like the oil cooler.
What is the best way to find out the cause of the coolant in the oil?
How do I test the Oil Cooler?
Thanks in advance.
David

 

[2004LB7]

More than likely head gasket or the injector cups. Oil cooler mixing is rare. Maybe pull the valve covers and see if there is any evidence of coolant around any cups

 

[dgalvin66]

I had filled the coolant before seeing it in the oil. Yesterday I noticed that the coolant was low again and it was never run.
How do I check the cups? What will I be looking for?
How would I check the oil cooler to see if that is the problem? I have read a lot of problems being the cooler but nothing on how to check it.
How would I check the head gaskets?
I need all the advice I can get.