Amsoil 10W/30; 4, 046--2002 Subaru Forester

[UberWRX]

2002 Subaru Forester
2.5L H4
90% city; 10% highway
OEM air filter
Amsoil oil filter
Make up oil: 0 qts.
Time on oil: A little over 4 months
Miles on oil: 4, 046
Oil Type: Amsoil 10W/30 ATM

1st number @ 40,790; 2nd @ 32,700; 3rd @ 28,053; 4th @ 24,677; last are universal averages. Also, previous oil analyzed was all Mobil1 SS 5W/30 or 10W/30.

Aluminum: 3, 4, 4, 4, 4
Chromium: 1, 2, 1, 2, 1
Iron: 8, 12, 11, 11, 8
Copper: 5, 3, 5, 9, 3
Lead: 1, 1, 1, 2, 3
Tin: 0, 0, 1, 3, 0
Molybdenum: 8, 50, 51, 27, 50
Nickel: 0, 0, 0, 0, 0
Manganese: 0, 1, 0, 0, 0
Silver: 0, 0, 0, 0, 0
Titanium: 0, 0, 0, 0, 0
Potassium: 0, 0, 0, 0, 1
Boron: 44, 112, 102, 75, 58
Silicon: 6, 8, 8, 10, 10
Sodium: 2, 6, 7, 6, 5
Calcium: 1930, 2721, 2587, 2508, 2390
Magnesium: 622, 22, 58, 461, 149
Phosphorus: 842, 675, 703, 887, 755
Zinc: 960, 851, 768, 978, 880
Barium: 0, 0, 0, 0, 0

Viscosity: 65.0
Flashpoint: 405
Fuel: Antifreeze: 0.0
Water: 0.0
Insolubles: 0.3
TBN: 4.6

Blackstone's note: Nice improvement in both wear and fuel dilution. Neither were a major problem last time, but we are glad to see both lower in this oil. The TBN was 4.6, which is a strong reading and higher than the 3.3 we found last time. The viscosity was fine and no fuel dilution, moisture, or anti-freeze was found. Insolubles were low at 0.3%, showing excellent filtration. At 40, 790 total miles, we think this engine is doing very well mechanically, and the oil still has plenty of life left. Suggest leaving it in use for another 3,000 miles and resample at that point to monitor.

Me: Wow! Since the majority of this car's mileage comes from lots of idling and city driving, I was getting nervous about even pushing the 4K mile/4 month interval; let alone what Blackstone is now recommending. I'm very pleased to be able to extend the OCI's in this manner.

 

[Ugly3]

Looks like you have an engine and a half in there, congrats. Looks like the oil you use makes little difference.

You may want to consider a "top rated" Purolator Pure One filter for improved contaminent removal or at least a cost reduction.

Would love to see the same test done with a good dino oil just for comparison.

 

[Dave]

Oil looks great, you can definitely go out towards 7,500 mi intervals with this engine. The Amsoil seemed to produce slightly better numbers than the M1.

Did you skip an analysis between the 1st and 2nd? There's 8k miles in between those two.

 

[UberWRX]

quote:

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Originally posted by Dave:
Oil looks great, you can definitely go out towards 7,500 mi intervals with this engine. The Amsoil seemed to produce slightly better numbers than the M1.

Did you skip an analysis between the 1st and 2nd? There's 8k miles in between those two.

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I'm glad you pointed out the difference between the Mobil1 and Amsoil results. It's enough for me to stick with Amsoil, especially since I'll be able to extend the drain intervals. Talk about cost effectiveness.

What amazes me even more is the fact that the miles on the Amsoil were considerably rougher than those on the Mobil1.

Yes, I had skipped an analysis. The OCI prior to the current Amsoil run was on Mobil1 SS 10W/30 with a Purolator Pure One oil filter.

Ugly3 mentioned using the Purolator Pure One w/ Amsoil; however, I had used the aforementioned oil filter on all the Mobil1 OCI's. At this point, I'm happy to stay with Amsoil's oil filter.

As I mentioned in my original post, this car experiences a trememndous amount of idling and city stop-and-go driving. I'll be curious to see if it's possible to have the same results in the winter. My feeling is that it will not be, because of increased fuel dilution.

Thanks for the replies!