I got mine 2 years ago at just shy of 13k miles. I change oil and both filters every 5k miles to be on the very safe side. My diesel shop agrees with that and said that if it was their engine they would do that interval. I too added the Hot Shots stuff but now do the Archoil oil additive too. I also add cetane booster to every fill of fuel just cuz it seems like a good idea with the ULSD fuel we have. I just do not trust the long oil runs and neither does this shop. They know a lot about the 6L and have a few of them themselves. Still a new engine with only 41k on it but I want it to last a very, very long time so I spend the extra money on the oil and filter changes.
All things being equal - fat people use more soap.