Any idea to stop minor oil consumption?

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Over 100,000 km of ownership of my old C-class, the oil consumption has been about 1L/5,000 km and is now around 1L/10,000km since i fixed a leak. It doesn't matter what oil i use, and i've used many PCMO xW40. I know that burning oil at this rate is totally acceptable but this car is so reliable it is boring and i always want to experiment with something. Here's a list of things to try next, take your pick:

1. Try the thickest HDEO 15W40 i can find.
2. Try Valvoline MaxLife.
3. Try 20W50.
4. Mix one or two quarts of 20W50 with my usual 5/10W40 to thicken it up.
5. Replace valve stem seals.
 
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1L per 10000km isn't much. i'd be fine with that. Once the consumption gets to 1L/qt per 3000km or 2000 miles is when you need to be concerned.
 
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Over 100,000 km of ownership of my old C-class, the oil consumption has been about 1L/5,000 km and is now around 1L/10,000km since i fixed a leak. It doesn't matter what oil i use, and i've used many PCMO xW40. I know that burning oil at this rate is totally acceptable but this car is so reliable it is boring and i always want to experiment with something. Here's a list of things to try next, take your pick:

1. Try the thickest HDEO 15W40 i can find.
2. Try Valvoline MaxLife.
3. Try 20W50.
4. Mix one or two quarts of 20W50 with my usual 5/10W40 to thicken it up.
5. Replace valve stem seals.
Valve stem seal issues are blue smoke on a cold start. Once engine heats up no blue smoke. The cheapest fix could be changing your PCV.
 
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What is your OCI? I would change the oil at the 10,000km mark when you’re down one liter.

The usage is pretty minor at this point.
 
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Why would the government care? 1 quart every 3000 miles or longer is a non-issue for all practical purposes.
Why , look at the hoops the manufactures have to go through to sell the junk they sell now to save 1 mpg . Let alone design a engine to purposely burn oil. Just sounds like a crap design to me. I do understand every engine does burn a slight amount it can't help but get past the rings. Never owned a vehicle that had any oil burning problems myself.
 
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Why , look at the hoops the manufactures have to go through to sell the junk they sell now to save 1 mpg . Let alone design a engine to purposely burn oil. Just sounds like a crap design to me. I do understand every engine does burn a slight amount it can't help but get past the rings. Never owned a vehicle that had any oil burning problems myself.
All engines burn some oil, at least past the rings and valve guides. The question is how much. It may be so little there's no difference on the dipstick after 5,000 miles. Or it may be so much that you have to add oil between changes. Burning oil may or may not be a defect, depending on the engine and how much it burns. Another factor is how you drive. If you drive like a teenager using frequent WOT to redline, the engine usually burns a bit more than it does if you drive like grandma.

It makes sense to check for leaks and some standard things like PCV. But if all that is fine, it might not be a problem that needs fixing. I've got an old Subie that has burned 1 qt. every 3000 miles since I bought it new. Now it's 20 years old with 6 figures of mileage and it's always been a reliable car. If it ain't broke, don't fix it!
 
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To address stuck piston rings you can try 'diesel' oil in 15w-40 for two oil changes with say 3-5k km OCIs.
If rings are worn, then there isn't much you can do without engine overhaul.
To address leaking valve stem seals you can try high mileage oil or Oil Saver as suggested above.
 

M119

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What is your OCI? I would change the oil at the 10,000km mark when you’re down one liter.

The usage is pretty minor at this point.
OCI is 10,000 km. After about 5,000 km it's down slightly below the middle and i top off with 0.5L to bring it back closer to the max and when i change it 5,000 km later it's down a bit below the middle again and i drain roughly 5L. (oil change is 5.5L). Or i only pour 5L in at OC and add 2x 0.5L during the OCI, it's always the same consumption.
 

M119

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To address stuck piston rings you can try 'diesel' oil in 15w-40 for two oil changes with say 3-5k km OCIs.
If rings are worn, then there isn't much you can do without engine overhaul.
To address leaking valve stem seals you can try high mileage oil or Oil Saver as suggested above.
If my rings were stuck it can't be an issue anymore. It's a very well maintained car and i did a bunch not to say way too much 5,000 km OCIs in this car. And rings are nothing like the low tension rings Toyota or others are using. It would take a lot of abuse to have them stuck and clogged.
 

SR5

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Is it leaking or burning? If burning use a quality engine oil flush every time you change the oil and use a HM engine oil.
 
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