Any reason NOT to run 15K OCI with M1EP on a Subaru NA 2.5 boxer (80% highway) ?

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Ahhj back to the Blackstone UOA! Why would you pay for this? Their cheapest analysis is $30. Just change the oil. Never understood why anyone takes the times to produce a sample and send it off for analysis. For the less than the cost of the analysis I can change the oil and filter .

Some you would rather spend a dime to save a nickel.
I don't recall mentioning any companies for a UOA. I pay a little under $10 plus postage for a UOA which includes TBN. Money very well spent IMO. Then I know for certain how my air filter and air filter related plumbing is working, if my fuel injectors have issues, if a head gasket is starting to fail, and if my OCI needs to be tweaked, etc. Win win for me, I feel that I'm spending a nickle to save a dime, or more. ;)
 
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Ahhj back to the Blackstone UOA! Why would you pay for this? Their cheapest analysis is $30. Just change the oil. Never understood why anyone takes the times to produce a sample and send it off for analysis. For the less than the cost of the analysis I can change the oil and filter .

Some you would rather spend a dime to save a nickel.
You realize that the suggestion could be for the OP could establish baseline data for this combination so that he could feel confident in this combination for longer right? Not necessarily to do a UOA every interval.
 
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Ahhj back to the Blackstone UOA! Why would you pay for this? Their cheapest analysis is $30. Just change the oil. Never understood why anyone takes the times to produce a sample and send it off for analysis. For the less than the cost of the analysis I can change the oil and filter .

Some you would rather spend a dime to save a nickel.
In general I agree. I never liked extended OCI but for those who do it you need to know how much life is left in the oil, once you have a good idea then I probably wouldn't do a UOA every OCI. I do use a UOA when I suspect fuel dilution or coolant or after a rebuild or major wet gasket replacement eg wet intake.
 
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In general I agree. I never liked extended OCI but for those who do it you need to know how much life is left in the oil, once you have a good idea then I probably wouldn't do a UOA every OCI. I do use a UOA when I suspect fuel dilution or coolant or after a rebuild or major wet gasket replacement eg wet intake.
Exactly. Once you establish how long the oil can go, no need for multiple reports unless something changes, or you suspect a problem. It's been 5 OCI's since my last UOA in our most used vehicle, and I have no plans on doing one anytime soon. But if someone wants to extend an OCI and eliminate any guesswork a UOA is IMO the best way to go.
 
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You realize that the suggestion could be for the OP could establish baseline data for this combination so that he could feel confident in this combination for longer right? Not necessarily to do a UOA every interval.
UOA really doesn't provide any info on oil cleanliness or the amount of buildup that is occurring internally. Engines with low-tension piston rings are very sensitive to deposits.
 
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What got you into trouble in the first place? Why was this engine rebuilt and a new long block ?
Was it lack of maintenance? Inadequate oil changes?
Just abuse , and driven hard?

was a tolerances of which stuff is engineered to you can't build junk anymore and put junk on the road. I think any vehicle and any engine should reliably run for at least 200k to 250, 000mi without any major failures
 

FZ1

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Using M1EP 0w-20 with Fram Ultra. The 12K warranty on a short block replacement is up. So far the oil consumption is around 1/4 qt in 7500 miles. We take weekly of highway trips of 30-250 miles so I doubt that fuel dilution is an issue. Not a GDI engine.

Mobil claims 15K (old) and 20K(new) between oil changes with M1EP.

Given this usage, is there any real reason not to go with 15K OCI's?
15k seems too far. Maybe your vis is down and that's why it's starting to use at 7500. So 7500 seems like a good oci. Try M1 Advanced Fuel Economy 0w-20...It runs smoother in my 2.5 Camry than the EP. AFE is 8.8 vis vs. EP at 8.6 vis. Jmo Hope this helps.
 
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Ahhj back to the Blackstone UOA! Why would you pay for this? Their cheapest analysis is $30. Just change the oil. Never understood why anyone takes the times to produce a sample and send it off for analysis. For the less than the cost of the analysis I can change the oil and filter .

Some you would rather spend a dime to save a nickel.

Maybe I want to do a short OCI and do an analysis too. Maybe I just want to do an oil analysis for fun. Maybe I want to find out what the best OCI is for my vehicle and driving regimen. Maybe I want to make sure I don't have coolant in my oil. Maybe I like having data. There are people here who paid nothing for their oil after rebate, so maybe they figure the cost of a UOA is a reasonable contribution to their vehicle's maintenance. What does it matter? It's their money, not yours.

Also, the NAPA analysis kit is half the price and includes TBN, so there's that as well.

This is an oil geek website. People come here to discuss this stuff. There is merit in discussing the cost of a UOA vs an oil change, but to ask "why would you pay for this" well, pick one of the reasons above, or any reason, or no reason.

If you don't like it, you're free to choose another website to express your opinions. But if you're going beat up people and ask them why they would pay for a UOA, I, personally speaking, will probably put you on ignore.
 
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If the spec calls for dino or semi-syn, I am fine running longer OCI with full synthetic but nothing crazy. E.g. if the recommended OCI is 5k on dino, I might go 7.5k on synthetic but only if plenty of highway miles. If the interval is 7.5k, I might go 9.5k with plenty of highway, but no further. 10k (or longer) OCI is just not smart when quality oil is so very cheap. Also be sure the oil filter is up for the extended interval, of course.
 
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Subaru don't like M1? But, If you find out what they like, please let me know.
I figured out the care and feeding of a EJ253 and FB20 but the FB25 remains a mystery. It seems to want more HTHS than a 20 but not all of a 30. Maybe a candidate for the old 1 quart of 5W30 and balance of the 0W20. I ran EP in a FB25, It seemed to like it: Noisy, but powerful - at least from the passenger seat perspective.
That same engine got the SoA dealer consumption test. Surprisingly and magically, it stopped consuming large amounts of oil. I asked the service writer, what did you put in there? "Just regular bulk oil sir" At the tim,e that was PEAK 0W20 with a Danica Patrick photo on the bottle. The engine clattered on the oil loudly when it got hot, but ran well for trips of 15 miles or less.

Q: How long is you 80% highway trip one way daily? How many miles per year?
I would stick to 10K given my two UOA on the more reliable and quieter FB20 motor
Good luck. - Ken
I'm just fascinated on how you can selectively pick out the pros and cons of oils in your engines;)...can't tell a lick of a difference in my fb25...
 
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UOA really doesn't provide any info on oil cleanliness or the amount of buildup that is occurring internally. Engines with low-tension piston rings are very sensitive to deposits.
Fair point, I still think a siphon UOA at 7000 miles would be a better approach than blindly going into such a long interval based on anecdotal advice from others.

Don’t really get the desire for a 15k interval from the OP. Sounds like the original engine had issues and it’s not like they’re some medical courier driving 600+ miles a day where 5000mile intervals would mean changing weekly (although I think weekly oil changes would be a dream for some people on here :) ).
 
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I have personal experience with a 2018 Subaru Outback 2.5L port injected engine that developed oil consumption issues AFTER I did a 13,000 mile extended drain interval using M1 EP 0w20 and a Fram Ultra 7317. The engine went from consuming little to no oil to consuming up to one quart of oil every 6000 mile interval. I would caution against doing any extended OCI and only recommend the 6000 mile oil change interval that Subaru now recommends. Trying to be cheaper than oil will likely cost you in the long run.

I have come to personally subscribe to what the man in the video below is describing:

 
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I'd try it, but with M1-EP 10W-30. Very low amounts of VM help with keeping pistons clean.

$24.47 at Walmart - $15 rebate = $9.47 for 5 quarts currently.

Also, 0W-20 recommendation is ONLY for Subaru's corporate fuel economy fleet averages. Subarus thrive on thicker oil. That said, I wouldn't go too thick in an engine with that little power.

And, with 10W-30, it should consume less.
 
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Ahhj back to the Blackstone UOA! Why would you pay for this? Their cheapest analysis is $30. Just change the oil. Never understood why anyone takes the times to produce a sample and send it off for analysis. For the less than the cost of the analysis I can change the oil and filter .

Some you would rather spend a dime to save a nickel.
I was of that philosophy, but I did a UOA to see how shot the oil was, then I extended the OCI by 50%
for the rest of the vehicle service life That saved me some bucks. The Subaru OCI of 6K miles was very conservative givin our use of this vehicle, running 23K mainly high speed highway miles per year.
 
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I have personal experience with a 2018 Subaru Outback 2.5L port injected engine that developed oil consumption issues AFTER I did a 13,000 mile extended drain interval using M1 EP 0w20 and a Fram Ultra 7317. The engine went from consuming little to no oil to consuming up to one quart of oil every 6000 mile interval. ...
I don't think Subaru will ever figure out how to make a 2.5 litre engine that lasts.
The 2 liter seem to do well.
You would think making the bore smaller would help, but no.
I don't like BOXERS anyhow. The wife's new DI 2.5 sounds like a bucket of parts ready to fall apart.

The Dog is great, the engine, though, is a dog.
 
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I don't think Subaru will ever figure out how to make a 2.5 litre engine that lasts.
The 2 liter seem to do well.
You would think making the bore smaller would help, but no.
I don't like BOXERS anyhow. The wife's new DI 2.5 sounds like a bucket of parts ready to fall apart.

The Dog is great, the engine, though, is a dog.

The engine is not problematic, I know of several that have gone 300,000 to 400,000 miles if not more but the key is proper maintenance without trying to cut corners or penny pinch with things like extended oil change intervals, etc.
 
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The engine is not problematic, I know of several that have gone 300,000 to 400,000 miles if not more but the key is proper maintenance without trying to cut corners or penny pinch with things like extended oil change intervals, etc.
No, the EJ and FB engine's are problematic I have a stack of TSB and recalls to prove it. The engine that I extended the OCI on was the BEST running one, ran better when it was traded in than at 20K miles never burned a drop of oil.
The wife latest one sound like a box of parts ready to grenade - absolutely unacceptable. And that's a new design.

There is nothing wrong with properly extending an OCI if the Manufacturer is overly conservative to accommodate the worst driving conditions and anticipated usage.

I see you have a new ouback too, have you changed the oil yeat and what are you running for oil and filter?
I was going to go back to factory subaru stuff, just because the Magnatec didnt quiet anything down.
I liked the Subaru 0W20 in the FB2.0 Crosstrek
 
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No, the EJ and FB engine's are problematic I have a stack of TSB and recalls to prove it. The engine that I extended the OCI on was the BEST running one, ran better when it was traded in than at 20K miles never burned a drop of oil.
The wife latest one sound like a box of parts ready to grenade - absolutely unacceptable. And that's a new design.

There is nothing wrong with properly extending an OCI if the Manufacturer is overly conservative to accommodate the worst driving conditions and anticipated usage.

I see you have a new ouback too, have you changed the oil yeat and what are you running for oil and filter?
I was going to go back to factory subaru stuff, just because the Magnatec didnt quiet anything down.
I liked the Subaru 0W20 in the FB2.0 Crosstrek

Yes I have completed three oil changes on the 2021 Outback 2.5L with the most recent one being yesterday for the 18000 mile interval. I have been using up my stash of Valvoline Modern Engine 0w20 and Wix 57055 filters. No problems to date.

I find it amazing that for all the complaining and worry I hear about head gaskets and other potential issues with this engine design you say you have no issue with yours, while claiming it is inherently problematic, and essentially claim that extending an OCI will not contribute to anything considered problematic. It just seems to be a bit inconsistent.
 
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Subaru don't like M1? But, If you find out what they like, please let me know.
I figured out the care and feeding of a EJ253 and FB20 but the FB25 remains a mystery. It seems to want more HTHS than a 20 but not all of a 30. Maybe a candidate for the old 1 quart of 5W30 and balance of the 0W20. I ran EP in a FB25, It seemed to like it: Noisy, but powerful - at least from the passenger seat perspective.
That same engine got the SoA dealer consumption test. Surprisingly and magically, it stopped consuming large amounts of oil. I asked the service writer, what did you put in there? "Just regular bulk oil sir" At the tim,e that was PEAK 0W20 with a Danica Patrick photo on the bottle. The engine clattered on the oil loudly when it got hot, but ran well for trips of 15 miles or less.

Q: How long is you 80% highway trip one way daily? How many miles per year?
I would stick to 10K given my two UOA on the more reliable and quieter FB20 motor
Good luck. - Ken

I have a theory. Dudebro buys a WRX and swaps it to mobil1 oil because it's a highly rated , good oil. Then he discovers how easy it is to bolt on mod your Subaru to much higher power levels. Then the stock WRX (not STI) internals let go on a hard pull with no tuning , supporting modifications and 15PSI of boost.

At that point it's the fault of mobil1.

With that said, the only time my FB25 consumed oil was on Mobil1 AFE. It went through 1/2 quart or so during the 6000 mile change interval. Every other oil change on other oil it's never needed a drop over the 6000 (or sometimes more ...) interval.
 
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