DD15 Oil Consumption

[tsolson]

Hi All,

Just looking for a bit of Detroit DD15 advice. I recently had an inframe done on my 2013 Freightliner Coronado. Has a demandated DD15 at 560HP that had 1.3 million km on it. We did all Detroit parts, pistons, liners, new cylinder head, injectors, turbo, rad. The shop ran it on a dyno after the rebuild to check it out and make sure everything was good, and start the break in. We changed the oil after 80 hours, it used about 2 liters in that period. The next period we did 200 hours as per the rebuilder, and it used about the same 2-3 liters in that period. Oil sample came back good.

The next 200 hour period the engine used 20 liters of oil, oil sample still showed no issues.

the next 200 hour period, it used approx 25 liters of oil, but i haven't received oil sample results yet.
we have 75 hours on this oil change, and its already used about 16 liters, so it appears to be getting worse. so in total it has about 750 hours on it since the overhaul, but the oil usage seems to be getting slightly worse.


This morning i pulled the turbo outlet to see if anything was gettting into the CAC, but its clean and dry. I pulled off the exhaust side to see if there was anything obvious there, but it seemed ok as well, just some carbon. i don't know if there's anything else i can check, or if it needs to go back to the rebuilder? Could the piston rings have lined up somehow after 300 hours to cause this oil consumption? The shop is about 14 hours away, so I'm trying to determine the cause before i have to take it back. I did a relative compression test with my laptop and it showed no issues. What else should i check?