My notes:

This last oil sample did see some long idle times at cold start ups. I did let the engine idle a couple of times for almost 20 minutes. Other time for about 10 to 15 minutes. Cold mornings and taking too long to get ready for work on this last sample. This last sample also saw more commute and city driving. The fuel dilution level has varied so far, but 2% is the highest. When I changed to oil, I did measure it and it was approx. 15 quarts. But 2% of 15 quarts is 9.6 ounces. I doubt my milk jug measurements could catch that. I did check the oil level consistently and did not see any raise in the level. Also, my mileage has not dropped off.. Over the last few months mileage seems to be about the same to slightly better. The truck has been running great. Conclusion: Less idle time warming up and closer monitoring of the oil level. The current oil (Motorcraft 15W-40) will be changed with 3,000 miles on it and a sample sent in for testing.

Current Oil: Motorcraft 15W-40
Next oil scheduled is Delo 400 15W-40.