So 17k on a reman long block, initial 1000 miles were broke in with synthetic oil (against manufacture requirements) as soon as I learned I flushed and refilled with DINO oil. That being said, I'm now at 17k and loosing about a quart every 200 miles. I REALLY believe it is my turbo (original to the truck, currently 451k miles. Not blowing smoke but the tailpipe is sooty... no oil "leaks" under the truck.

If the turbo was leaking oil, how would it be indicated?

at $600 to get a reman from Thoroughbred Diesel and I just better replacing the turbo than paying a shop $300 just to find the oil leak?

Is there a better/cheaper place to get a reman turbo?

WHAT is the possibility that 1000 miles on synthetic could have caused issues with the OIL ring on any or all of the pistons during break in?

Thanks guys.

I don't think the synthetic oil hurt anything. I take it as a precaution, you have checked for oil in the coolant? Any remote possibility is the crank case vent tube but you should readily see an oily mess on the underside. Have you checked for blowby?

Unless you can find a visible oil leak on the outside of the engine somewhere, Loosing that much oil is likely a possibility it's the turbo. Have you removed the downpipe from the hot side for a look. The other possibility is rings but you would be seeing noticable blue smoke.

No I haven't broken the turbo loose... if I'm going to that level I'm going to just replace it... no oily mess, no visible leak. No "obvious" smoke... Would it smoke if it was leaking out the exhaust side of the turbo? I mean I'm down to two possibilities... oil rings gummed up or turbo leaking on the exhaust side... unless I get other possibilities from the group...

1 hour ago, Tim Waldo said:

That being said, I'm now at 17k and loosing about a quart every 200 miles. I REALLY believe it is my turbo (original to the truck, currently 451k miles. Not blowing smoke but the tailpipe is sooty... no oil "leaks" under the truck.

If the turbo was leaking oil, how would it be indicated?

Observing soot at the end of the tailpipe is normal for this era of truck, especially if you have larger than stock injectors.

Disconnect the compressor discharge plumbing from the turbo and inspect for an oily mess. Then, disconnect the exhaust band on the exhaust side and inspect for the same.

1 hour ago, Tim Waldo said:

WHAT is the possibility that 1000 miles on synthetic could have caused issues with the OIL ring on any or all of the pistons during break in?

It is possible. The hone pattern intentionally put into the cylinder walls is used as a mild abrasive to condition the outer wear surface of the piston rings for the first 1,000 miles or so of driving. During this period of time, the best mating of the rings to the cylinder wall will occur, resulting in the least oil consumption and least engine blow-by.

Using a slippery synthetic oil during break-in reduces the effectiveness of the abrasive characteristics of honing the cylinder walls - it will have a more likely effect of polishing the piston rings and the cylinder walls, resulting in more oil consumption and more engine blow-by.

Try performing the oil cap rattle test for the poor man's method of checking engine blow-by.

• John

Edited Monday at 03:41 PM1 day by Tractorman

none...

https://photos.app.goo.gl/PHtop7t4BVnAiWD57

Valve guides and valve seals can leak oil some but typical not much because normal both exhaust and intake are under pressure. Like Beast long run downhill like my last trip to Heaven's Gate then I see the blue oil smoke as I throttle up from the bottom of the grade. Typically that how valve guides oil leak is seen. No blow by issues but leak oil past at zero pressure moments like running downhills.

6 hours ago, Mopar1973Man said:

Valve guides and valve seals can leak oil some but typical not much because normal both exhaust and intake are under pressure. Like Beast long run downhill like my last trip to Heaven's Gate then I see the blue oil smoke as I throttle up from the bottom of the grade. Typically that how valve guides oil leak is seen. No blow by issues but leak oil past at zero pressure moments like running downhills.

but a quart every 200 miles??

I'm pretty much betting on the turbo... guess I'll break it apart this weekend and see if I have residue on the exhaust side.