First I had my oil tested at Blackstone - thankfully with negative results. Potassium or sodium levels in the oil would indicate coolant in the oil.
Second, since I am new to the truck, I didn't know if the "soot" was residual from a prior event or symptoms of a new problem. I drained enough coolant (into a clean bucket to put back in) and removed the coolant bottle which I cleaned with soapy water. I could only get a rag into the first chamber so the other three chambers had soot which I couldn't remove. My goal in doing this is to see if the soot returns (which thankfully it has not).
Third, I put on a Dieselsite coolant filter.
Finally, I checked the oil dipstick for irregularities (which I did not see).
I'll try to post pictures later on.
As an aside, my oil cooler orings were recently replaced. I'm sure others will chime in and suggest that oil - coolant crossover often occurs as a result of deteriorated orings in the oil cooler.
Except for clear condensation, my degas bottle is clean at this time.
Although I forgot to mention it above, I did pressurize my coolant system to 15psi and I didn't see a pressure drop over the 15 +/- minutes that I kept the pressure on. In case it helps, A/Ox4 puts out a YouTube video on how to pressure test the cooling system.
Unless the soot returns, I'm going to assume the soot was from a residual problem. If I were you, I would do the same.
I think the other thing I read about when researching the issue was the potential for cracked injector cups. I believe you can test that by removing the injectors and pressurizing the coolant system. Unless the soot returns, I don't think it's necessary to go there.
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.