MMO for Oil Consumption - trying it out

[Dominic]

So after 105,000 miles the Subaru is finally consuming 1/2qt or so every 1000 miles. I'm now trying 1qt of MMO in the sump as an oil additive for the next 1000 mile interval before my oil change to see if it helps some of the consumption. I will use this thread to report back as time goes forward on the progress.

Anyone have any good stories though about MMO helping their oil consumption? I am hoping to clean up any sticky oil control rings.

 

[TrevorS]

A friend of mine had a similar situation and added MMO as per instructions.

500 miles later his oil consumption had increased and he reported a noisy engine. His mechanic told him his oil had thinned out and promptly changed out the oil. The noise reduced but never went away. There was no noise before MMO as per my friend. Same with oil consumption. It was permanently worse than before MMO.

The same mechanic eventually took the engine apart to perform a mechanical fix and reported damage which he felt was a result of the oil being thinned out by MMO.

 

[71Chevyguy]

I have used it before to clean things up but I used a small bottle of it and usually also substituted a quart of really thick oil to offset the very thin MMO. I do not fell personally that it is ok to use for example 5w30 and a quart of MMO. To me that would be way too thin and not happening in my engine. I would use 10w40 and a small bottle personally, not a full quart of MMO.

 

[demarpaint]

Dominic- I had good luck with increasing compression and reducing oil use with MMO. However I would look into a Kreen piston soak, and replace if you haven't already done so your PCV valve, with a OEM valve. If you have worn or damaged parts you're out of luck and moving to a heavier grade oil might be your only option. Good luck!

 

[NHGUY]

Years ago a contractor bought a used Toyota VAN (the snub nose one) from a big Toyota/Ford dealer.The engine had a "tick" in it,so he proceeded to add 1-1/2 to 2 qts of MMO.Shortly thereafter the engine froze up.The dealer took it apart,put the engine in boxes inside the van and promptly handed him a bill for dissasembly.They said that the MMO thinned the oil,and the engine overheated and froze up...no warranty.He was PO'd,as MMO had been around for decades and should have been safe.He picketed the dealership off the interstate claiming they didnt stand behind their vehicles.The dealer got the guy removed from the roadway by state police.He took his gripe to the newspaper and trying to avoid a public interest disaster,the dealer offered to pay some of the expense.

 

[kr_bitog]

MMO reduce oil consumption on neglected engine, e.g. Dino oil with long OCI
If your engine is not neglected, the stuff to try is mobil 1 high mileage. If it does not stop the consumption in 2 oci, times for disassembly to replace damaged parts

 

[Clevy]

Originally Posted By: TrevorS
A friend of mine had a similar situation and added MMO as per instructions.

500 miles later his oil consumption had increased and he reported a noisy engine. His mechanic told him his oil had thinned out and promptly changed out the oil. The noise reduced but never went away. There was no noise before MMO as per my friend. Same with oil consumption. It was permanently worse than before MMO.

The same mechanic eventually took the engine apart to perform a mechanical fix and reported damage which he felt was a result of the oil being thinned out by MMO.


Do tell. We love data here. Exactly what damage incurred due to thin oil

 

[Falken]

I don't think MMO will fix the inherent design flaws of a higher mileage Boxer engine.

Love Subaru, wish they'd dump the Boxer.

The only thing I would try is 3-4 bottles of Redline Complete (has Techron in it) added to the gas tank.

I'd use a whole bottle per fill up for 3-4 tankfuls in a row.

I'd run a few 5,000 mile runs of Pennzoil Platinum to see if you can clean some crust out of the oil control rings.

 

[SteveSRT8]

I have used MMO for decades in dozens of engines. Never appeared to damage anything. It's to be expected that an additive will be put into a "hopeless case" once in a while, but MMO is relatively harmless for MILLIONS of users and has been around a LONG time.

That said, I do not consider it a very good cleaner, there are better ones if you suspect oil control ring coking as is common in high mileage engines. Try some Kreen used as per instructions on the can. Worked wonders here in service trucks and friends old clunkers.

 

[Donald]

Originally Posted By: TrevorS
A friend of mine had a similar situation and added MMO as per instructions.

500 miles later his oil consumption had increased and he reported a noisy engine. His mechanic told him his oil had thinned out and promptly changed out the oil. The noise reduced but never went away. There was no noise before MMO as per my friend. Same with oil consumption. It was permanently worse than before MMO.

The same mechanic eventually took the engine apart to perform a mechanical fix and reported damage which he felt was a result of the oil being thinned out by MMO.


While MMO may help with cleaning it has a negative effect on the lubricating properties of oil.

Much better off trying a cheap synthetic like ST.

A compression test should be done. But that may or may not tell the whole story.

 

[Eosyn]

I don't think MMO will stop oil consumption/leaks. I would try using HM oils for a few OCIs since they claim to help stop leaks.

 

[Bandito440]

Maxlife 10w-40 should help you out.

 

[Trav]

Originally Posted By: Donald
While MMO may help with cleaning it has a negative effect on the lubricating properties of oil.


Proof?

 

[Donald]

Originally Posted By: Trav
Originally Posted By: Donald
While MMO may help with cleaning it has a negative effect on the lubricating properties of oil.


Proof?


I have posted proof in the past that when MMO was added to diesel fuel the lubricity of the diesel fuel was worse than without it. This was an industry standard test and has nothing to do with running a diesel engine. It only tests diesel fuel as an oil.

 

[gregk24]

If your trying to do some cleaning run a pennzoil synthetic, do two 3000 miles OCI and your engine will be pretty clean. If your going to use lots of MMO then I would go up a grade in oil to help counteract the thinning which it will do.

 

[Trav]

Apples and oranges. Diesel fuel is not engine oil its similar to kerosene which can be used to clean engine parts, its no surprise that it is not compatible with MMO.
Thats all you have? Pretty thin.

 

[Donald]

Originally Posted By: Trav
Apples and oranges. Diesel fuel is not engine oil its similar to kerosene which can be used to clean engine parts, its no surprise that it is not compatible with MMO.
Thats all you have? Pretty thin.


In the test when 2-cycle oil is added to diesel fuel the lubricity is better when MMO is added its worse. While I agree its not a perfect test, is close enough for me to leave MMO on the Walmart shelf.

 

[951Indy]

I recently became a believer in HM oil. My HM Bonneville 3.8 consumption was cut in half. This is using Castrol 10/30 HM, but I just stocked up on M1 HM 10/30. I expect similar results. We'll see.

I'd skip the MMO and get the oil changed to HM now, unless you're already using HM oil.

 

[SteveSRT8]

Originally Posted By: Donald
Originally Posted By: Trav
Originally Posted By: Donald
While MMO may help with cleaning it has a negative effect on the lubricating properties of oil.


Proof?


I have posted proof in the past that when MMO was added to diesel fuel the lubricity of the diesel fuel was worse than without it. This was an industry standard test and has nothing to do with running a diesel engine. It only tests diesel fuel as an oil.


Despite the data presented I fail to see the relevancy at all to the OP's issue.

 

[Trav]

No surprise 2 cycle oil works better in diesel its formulated to work with gasoline which is also a solvent.
One could argue that MMO is also recommended for gasoline but the question is what effects do gasoline and diesel have on the products base ingredient.

It seems to me you are judging the lubrication properties of a product which may not be compatible.

Now let me ask this question. How would 2 cycle oil work when added to engine oil?
Any cleaning effect? compatibility issues?