oil consumption

[artfull dodger]

Ok, going thru oil just a wee bit on my 94 C2500. Daily driver to work, I can go from the full mark on the stick to an 1/8th inch above the add mark in roughly 200 miles thru the work week. Engine has 149K on it, age of injectors/pump is unknown. NO drivablity issues, idles smooth, starts easily, runs on all 8, even after sitting for 10 hours in 20'F temps at work. yes she has blow by out all the normal spots, no leakage to the ground of oil or anything else. Just goes thru it. Using Shell Rotella T 15w40, which has what I have used in every diesel I have owned. Do I just put up with oil usage and start planning to replace the engine next spring/summer or am I missing something. I tried with the CDR vented to the ground vs hooked to normal spot with no real change in oil consumption. With my extension tube, I see the vapor, but there is no liquid oil in the tube or on the part of the frame where I have it mounted. A recent 400 mile trip at highway speeds took her from full to just below add. I get in the upper teens for MPG's. Truck is emaculate, was owed by a diesel mechanic before myself, body is 98% rust free, only a few small bubbles in the bottom of one door. My usual go to place for a rebuilt 6.2/6.5L is nolonger a viable choice from my recent research(Diesel Depot/Avant Salvage). Just want to look at all options before things get worse, I could trade it off right now if I needed to, just do not really want to. But I cannot also afford any long down time due to failure as its my way to work. Thanks for any ideas in advance
https://image.ibb.co/cFJxGG/mytruck.jpg

[JeepSJ]

Valve seals.

[artfull dodger]

Doesn't help that I cannot find a shop localy that is famillar with this older engine, being the home town of Chrysler's transmission plants, most everybody drives Dodgers or something with a Powerstroke in it. My old truck is an oddity in the local diesel scene.

[Yukon6.2]

Next oil change try a different oil.
KW dealer changed the oil in my Kenworth to a Rotella oil.It didn't like it,or should i say it loved it because my oil consumption doubled till it was changed out again.

[JohnC]

Rotella oil...it loved it because my oil consumption doubled till it was changed out again.

Changed out for what?

[artfull dodger]

Yes, whats in the KW now? Trying to not go to a much more expensive full synthitic oil.

[Robyn]

ANYLEAKS ???

Replace the Crankcase vent valve (Passenger side Valve cover area .. round can)

Yank off the air inlet to the turbo and see if the turbo inlet is really SLOPPY

With the engine warm and at idle, remove the oil filler cap and observe the vapor coming out (If any)

If there is a large amount of vapor/smoke from the oil filler pipe then it means the rings have a fair bit of blowby into the crankcase.

Raising the RPM slightly should clear the vapor/smoke...If not then there is an excessive amount of blowby.


If the turbo inlet is really sloppy with oil then the oil is being pulled from the crankcase because of excessive blowby.

A restricted air filter or fender passage can increase the incidence of oil pull over.

The other issue may be a leaking turbo "Hot side shaft seal or a heavily carbon'd up oil drain back from the turbo which will force the oil out the shaft seal into the exhaust stream.

A restricted turbo oil drain tube/ connector hose at the engine possibly, but not normal issue

Remove the exhaust down pipe from the turbo flange (Remove the band clamp and shift pipe to peek in the turbo)

If the turbo has fresh oily residue leaking around the hot wheel then you have a leak.

While you have the inlet of the turbo open check the shaft end play and radial play.

Some small radial play is normal with the engine shut down.

IN AND OUT IS NOT GOOD

Look and see if there are signs of the compressor (inlet wheel) has contacted the housing... (scuffing,galling of the inlet near the blades)


Any of these things can indicate a worn out turbo.


If it's not dripping on the ground then its going out the exhaust pipe.

Either through the turbo from oil pull over, hot side seal leak.

If these check out OK then the evil eye turns to piston rings.

Valve guides/seals can cause issues, but generally it is not a severe problem.

Check things and keep us in the loop.

Pics are very helpful such as below...

Fill pipe blowby
Turbo inlet

[Yukon6.2]

I am running a full synthetic in all my diesels that run in the winter.
It is sold by a Canadian company,which brands it under their own label.
They are based in Alberta,and have branches in Yukon and Alaska.
AFD is their initials,which is Alberta Fuel Distributors or Arctic Fuel Distributors in Alaska.
I thought i would try it because others recommended it.Plus it is reasonably priced.So far i have no complaints the C7 cat in my rollback has used hardly any oil since i changed it,most is probably leaks by the black dots on the floor where it is parked in the winter.The Kenworth which lives outside and gets used every week does use some oil still but way less than the Rotella.
I have a moose gooser on the KW so it is a pain to add oil,so that is my Butt dyno so to speek.I added oil last week and was trying to remember the last time it was done,and it must of been last winter because the bungy cord that holds my winter front was still on the gooser and had to be removed to let it down.
My experiences with Rotella Synthetic... others may vary.
But if interested i believe there are a few oil threads on here for amusement and reading.
Thomas

[john8662]

I'd wait till 1QT low and do an engine oil cleaning. Possibly stuck oil control rings.

Buy the 1qt engine oil cleaner, follow instructions (smells a lot like diesel fuel) then do a full oil change, suggest choosing another oil like Delo 400.

Rotella can make a perfectly sound engine that doesn't use oil, start to use a lot of oil. It used to be great stuff, not for older diesels now.

[Warren96]

How about Shell Rotella T1 SAE 30. Meets API service CF-2, CF? I've been using it for a couple of years now year -round to help keep my consumption down. I just use a trickle charger on it overnight to give it that extra kick it needs to get going in the morning. Shell claims it's''..suitable for day to day use in older turbowcharged and non turbo diesel engines"