2014 Forester XT, Mobil 1 and Formula Shell Mix

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Hello everyone! Here's a UOA of our 2014 Forester XT.

Oil used on this sample was 5 qts. of Mobil 1 0W-40 and 1 qt. of Formula Shell Full Synthetic 5W-30. Sump capacity is 6 qts. with oil filter change. OCI of 5,193 miles was from Nov. 11, 2017 at 72,668 miles to Mar. 26, 2018 at 77,861 miles. Mileage of vehicle when oil sample was taken is 77,861 miles.

I also replaced the engine air filter about midway through this OCI. Filter was replaced at 75,921.

OEM air filter was in use from Nov. 3, 2015 at 30,009 miles to January 28, 2018 at 75,921 miles. Filter had 45,912 miles at the time of replacement. New filter installed is an AEM Dry Flow filter.

Reason for not following Subarus's air filter replacement interval of 30K miles you ask? I've been around BITOG for a while now and read many posts regarding air filters becoming more efficient at filtering finer contaminants when used longer so I decided to install a filter restriction gauge and decided that I would replace the filter once I got to 15" of H2O vacuum on the Filter Minder (Self made up number to go by).

I then got to thinking what if by having a slightly more restrictive air filter all in the name of filtering efficiency, I could now be sacrificing turbo longevity since the turbo is now having to work harder (by how much I do not know) to compensate for the more restrictive filter so that the engine is hitting the target HP/Torque commanded by the ECU. This made me replace the filter sooner than I planned.

I had 2 reasons for having the UOA done.

1st/main reason for the UOA
At 60K miles, I installed 2 oil catch cans. 1 on the PCV side and another on the CCV (Turbo) side.

It has always bugged me whether the hose connections where properly sealed since the installation was somewhat custom. I sourced most of the hose used in the install. I wanted to see if I have been having dirt ingestion issues, plus the possible dirt ingestion from replacing the air filter midway through the OCI.

2nd reason for the UOA
This OCI consisted of many extremely short trips with a decent amount of 35 miles plus one way trip. I live in the DC Metro area to give you an idea of our winter conditions.

Driving pattern for the duration this OCI are as follows:
Monday - Oneway trip of about 35 miles into DC. Sits for 8 hrs. then started back up for a 2 mile trip within the city and then shut off.
Tuesday - 2 mile trip in the morning then shut off. Sits for 8 hrs. then started back up for a 2 mile trip within the city then shut off.
Wednesday to Thursday - Same as on Tuesday drive cycle.
Friday - 2 mile trip in the morning then shut off. After office hrs. on a Friday can either be another 2 mile trip then shut off then leave the vehicle for the weekend in DC or I tell my wife to take the vehicle home which then is 35 miles away.

During the above drive cycle, the oil temp. only gets to 150F to 175F.

There are weekends where we use it to travel to friends and families which are far enough to get the oil to full operating temperature which is around 194F to 210F.

Sorry for the long winded post but I wanted to give everyone a snap shot into the history of this UOA so that if there are figures that look amiss, people would be able to make sense of it. Everything looks good to me though! Let me know what ya'll think.

 
The wear metal levels look very good!
That calcium level would make me nervous about LSPI, but you have some moly and also elevated ZDDP levels (compared to a typical SN 5W30, say) to help mitigate that problem. LSPI concerns have me sticking to dexos1 Gen 2 and dexos 2 (just learned the latter standard also has an LSPI test) for the time being, but that's just my take on things.
I have thought about catch cans on and off since I bought the car and I'm guessing I'll probably never install any. I have been running the Subaru Carbon Clean and Top Engine Cleaner through a vacuum line using the special Subaru tool to try to help keep stuff from building up on the intake valves, actually got quite a bit of white smoke the last time and I hoped that meant it was actually doing something (Carbon Clean on that run). Do you find that the catch cans pick up a lot of nasty stuff?
I do wonder if you might have had a bit more fuel contamination than Blackstone reported given the low flashpoint...I guess it would fit in with short tripping in the winter. Others have found that Blackstone underreports fuel compared to other oil analysis companies.

Good looking report all in all, hope your FXT gives you good service for a long time.
I just had a valve body in my CVT replaced, just before 80kmiles, BTW. I suspect pretty strongly now that the wrong CVT fluid was used at my 60kmile service (standard instead of high torque), so I'm going to have to man up and do that change myself next time (think we talked about that process before).

EDIT - just noticed that your copper level is extremely low while the universal averages show much higher levels. I'm quite sure we don't have oil coolers as OEM, I wonder if a lot of FXT owners install them? Don't know where else that copper would be coming from...
 
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Virtus,

Yeah,LSPI also has me concerned but it is my hope that by having the catch cans, I am filtering out majority of the oil vapors and in doing so, IMO, I am further lessening the chances of LPSI. Maybe I should also start using oils that have LSPI suppression as part of its testing to cover both ends.

The PCV side catches a decent amount of oil vapors. During the summer time, it appears that I am collecting about 3 ounces (guesstimating here, I did not measure it) of oil during a 5K OCI. It may also be catching some unburnt gasoline since the oil in the catch can smells strongly of gasoline. In The winter months, I check it every 1K miles since it fills up much faster with both oil/gas vapors and water. I once went about 4K miles in the winter without checking it and when I did, the can was full and the engine had probably been sucking in oil for who knows how long.

The CCV/turbo side catch can also filters out a bit of oil but for a 5K mile duration, the amount is so minuscule. I am sure it is not even worth half an ounce, if that.

Regarding flash point, if my calculation is right, the average flash point of my Mobil 1 0W40 /Formula Shell Full Synth. 5W30 mix should be right at 437F. At 385F flash point, yup, it appears I have quite the fuel dilution. This is the reason why I choose the thicker oil to compensate for the dilution. To give everyone an idea of how this engine dilutes fuel, at the time of the oil change, I always make sure I am at the full marker on the dipstick. At 1K miles (my preffered interval to check the oil level), the oil level has probably risen by about an inch from full. This would then hold steady for the duration of the OCI. If it is in fact rising, I don't notice every time I check.

The operating temp. viscosity of the oil seems to have held up well though at 12.21 despite the fuel dilution. Mobil 1 0W40 has a 100C viscosity of 12.9 while the Formula Shell Full Synth. 5W30 is at 10.51.

About the lower copper level on my UOA analysis compared to the universal averages, I am assuming anybody who does a UOA on a Forester XT is an enthusiast.

While my goal is to get as many miles I can with this vehicle, a good number of them probably have tuned XTs and I am assuming a lot of them have installed an engine oil cooler from Mishimoto etc. inline with the factory cooler. This is probably where copper is coming from on the univ. avg. Another thing to take into consideration is a good number of Forester XTs are tuned (at least a good number of them that bother to get UOA done) and are probably putting out more wear.
 
Might just put in new oil up to half-way between the Add and Full lines, leaving it half-quart low (from full) at oil change time. Then watch the fuel dilution fill it up. Avoids any oil foaming from overfill.
Your kv100 visc did look perfect. No problems here.
Low insolubles at 0.1 too. TBN very high, nice.
Keep doing what you're doing for the most part.
 
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Common misconception that a "fan" or pump will work "harder" when pumping in a partial vacuum.

Vacuum = less energy expended, less atoms displaced = less work.

Cover you vacuum cleaner hose. Does it speed up or slow down?

I just see this comment a lot and thought it was high time to respond.
 
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ARCOgraphite,

I get your logic but using that logic in a turbo charged engine is IMO not applicable here.

A vacuum cleaner does not have a target Boost/HP/Torque that it is trying to maintain.

Based on my limited understanding of how modern turbocharged engines works, it is setup on maintaining peak power all the time unless of course the ECU detects knock etc. This is the reason why turbocharged engines are better at altitude because it compensates for the less dense air by way of the ECU sending signal to the waste gate actuator to send more exhaust gas to the turbine housing so that target boost pressure is met or at least close to it.

Just as how you put it, more vacuum is created by the loaded engine air filter. To me, this scenario causes the turbo to spin even faster than usual by having the waste gate send more exhaust gasses to the turbine so that it can compensate for the increase in vacuum the loaded air filter is creating. To me, this sending of more exhaust gasses causes the turbo to spin faster thus putting more centrifugal (or is it centripetal? I am not sure which one.) forces which in turn stresses it more. This is the reason why I am now sticking to the factory recommended AFCI (air filter change interval, can this be now a new website wide acronym? Lol.) of 30K miles since I feel like this is a good balance between taking advantage of filter efficiency increase as it gets loaded up and turbo reliability.
 
I was looking at it simply as: the work done is pumping the fluid (air) not spinning the turbo up to a higher RPM - that I considered a loss; though that you can consider working the turbo harder - though 90,000 rpm or 100,000 rpm No big difference

Depending on climate and dust, Ive gone two years (but not without fretting). The Car ran BETTER when replaced though with more WOT power. (Except when the dealer had a $12/hour grease monkey do it, and put the filter in backward and not sealing - Morons! All to Save a dollar with ex convicts - then MAJORLY displease the customer. I even has a !DO NOT OPEN! SERVICED 11/17 large tamper label.

On my Nissan My exhaust is melting down and buzzing internally so I have a problems at the back end now
smile.gif
 
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