Motul 8100 5W30, 5,900 miles, Subaru Forester XT

[bluesubie]

UOA by Blackstone and oil was in use December 23rd to March 6th.
I was pleasantly surprised with this UOA because I suspected that oil with a viscosity of 9.9 cst’s at 100C would shear to a 20 weight. I switched to the Motul because I was having high fuel dilution during the winter due to my short daily trips of five miles each way.

I was about ¼ of a quart low when I sampled this so I guess overall usage was about ½ quart in 6k miles. I’ll probably go with GC for my summer run since I have five quarts of it. I like the results with Motul, but shipping is expensive! I’ll run this to 7 or 7.5k max because I still have 9,000 miles left on my powertrain warranty.

Question about the properties. The viscosity and flashpoint “should be” numbers are different between GC and Motul (both posted in brackets). Why is that? Anything to do with typical 0W30’s or GC being ACEA A3?

Current; gold GC @ 7,000; gold GC @ 7,478; gold GC @ 6,144; green GC @ 5,930; M1 5W30 @ 5,774.

Code:

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Equipment make: Subaru

Equipment model: 2.5L Turbo

Oil use interval: 5,900

Oil type & Grade: Motul 8100 Eco-nergy 5W30

Make-up oil added: .25 qts.

Miles on unit: 59,650

Air filter: OEM

Oil filter: OEM



Dennis: Sodium dropped again, and wear looks terrific.

The TBN read 4.8, still plenty of active additive left

in the oil. We’re glad to see that you haven’t changed

this oil yet. It still has plenty of life left in it.

No fuel or antifreeze found. Add another 2,000 or 3,000

and check back. If wear still reads low, you may not

even need to change it at that point.



Aluminum 4 5 4 4 4 6

Chromium 1 1 1 1 1 1

Iron 11 12 16 11 10 15

Copper 6 8 7 10 6 20

Lead 2 3 3 3 2 2

Tin 0 1 0 1 0 0

Molybdenum 3 2 9 4 12 63

Nickel 0 0 0 0 1 0

Maganese 0 1 0 0 0 0

Silver 0 0 0 0 0 0

Titanium 0 0 0 0 0 0

Potassium 0 2 0 0 0 3

Boron 1 0 0 1 14 115

Silicon 14 13 15 15 18

Sodium 11 19 18 6 2 6

Calcium 1252 1783 2165 1689 2582 3394

Magnesium 953 530 436 398 106 10

Phosphorous 932 796 816 754 680 764

Zinc 1025 974 1011 909 818 904

Barium 0 0 0 0 0 1



Properties

SUS Viscosity @ 210F: 58 66.2 66.4 64.4 64.8 57.8 [56-63] [58-65]

Flashpoint: 370 380 380 385 365 395 [>365] [>385F]

Fuel %: .5 TR .2.3 .5 1.0 .5 [
Antifreeze: 0 0 ? 0 0 0 [0]

Water: 0 0 0 0 0 0[
Insolubules: .3 .4 .2 .5 .4 .5 [

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[unDummy]

Everything looks excellent.

I don't care for should be's. Don't worry about visc or flashpoint. When fuel is at .5 flashpoint was lower. Your short trips during winter shows.
For viscosity, use a visc calculator and compare to SAE J300 and oil brands data specs.

Si levels are consistent but makes me want to check the air filtration. What type of filter? when do you change it?

Sodium is there. Is it from the oil? winter salt paved roads? No potas and no positive for coolant, so I wouldn't worry about it. But Subaru has had some gasket and casting porosity issues. Use the Subaru antifreeze 'stop leak' with your coolant changes even if not needed for your year.

I would expect more wear/tear from a turbo motor but it isn't seen here. I'd wager that driving style is mature. Or, the slightly lower state of tune, when compared to STI, is just about perfect for this engine.

 

[bluesubie]

I can never figure out why my Si doesn't come down. I started the car with an Amsoil foam filter and then switched to OEM to try to bring down the numbers. It's changed every 30k and on one of the earlier UOA's, it was changed about 1k before the sample was taken. I've even had the dealer check the intake out to make sure there aren't any leaks. Maybe I should go to every 15k at a minimum.

I'm in NJ so I do drive on salted roads in the winter. The Subaru stop leak as a precaution is a good idea. I drive spiritedly once in a while, but not as much in the winter.

I've considered "fixing" my state of tune, but I'm not comfortable modifying the engine.

I plan to keep this car for a long time.

-Dennis

 

[bluesubie]

BTW, that's a typo on the mileage. It should be 51,650.