I'm not sure why some seem to do it more than others. Mine will drip out a little oil here and there for no apparent reason, but it's not much. It seems that a little oil vaporizes and then condenses in the tube. Eventually, you've got enough condensation to drip a little. That's the most plausible explanation I've heard. Diesels are kinda like radial engines. If they aren't dripping a little oil somewhere, you're out of oil.
It will also drip if your oil level is too high for some reason. Is there a chance it was overfilled at the last oil change? That can be easy to do if you didn't get all of the oil out last time. Mine will drip if it's much above halfway on the hatch marks, even if it's still within the reccomended range.
If you didn't overfill it, there are a couple more possibilities. If your oil level is rising, then you've probably got a leaking injector or pump. Basically, it's leaking fuel into the crankcase and causing your oil level to rise. There's a couple of ways to check for fuel, but the most accurate is just getting an oil analysis done. Blackstone labs does it for $22. 50, I think. Sometimes you can smell it too. That's pretty unlikely with only 30k on it and since you haven't beat on it. Another possibility is that you've got some blowby in the crankcase from a bad ring, but that's even more unlikely.
I really wouldn't worry about it too much. It's probably just condensation. Keep an eye on your oil level, and if it's not rising don't worry. I think somebody did a poll a few months ago, and most people said theirs dripped a little. TDR is an incredible source of information/experience, but sometimes it can be a little like reading a medical journal. After you see some "symptoms", you begin to worry about all the little things that
could go wrong. People don't post about every single time they got in their truck and it worked flawlessly.
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