Amsoil SSO 0W-30, 7477 mi., '08 Subaru WRX STI

[gathermewool]

Car: '08 STI

Total Miles: 39867

Miles On Oil: 7477

Filter: Subie OEM Blue

Use: A lot of bitter cold driving to work, 5 miles each way at low speeds, every day of the week for the first few months of the year - I'm sure this was what gave the Amsoil its beating. However, there is an EASY 500 mile trip to see the family on there, as well as plenty of 150 mile round trip drives to see the gf, which is why I expected a better showing from Amsoil. I also did one auto-cross, which included six 54 second runs on the course, but I can't imagine it was very hard on the oil, since it was more turning and braking than hard acceleration.

I drive pretty conservatively around town, but have fun every chance I get.

Based on the below results, I can't see how Subaru is recommending 7,500 mile intervals using synthetic oils. If neither Rotella T6 nor Amsoil SSO can handle a winter interval, than I doubt their oil can. I have a feeling that this next interval (my last on Amsoil,) which will be mostly warm-weather driving, will show a lot better.

 

[tig1]

Fuel may be the big problem here. Your FF is very low, in fact I don't remember seeing one like this. With only 40K on this engine you may need to go to 3K OCIs to make this engine last.

 

[INDYMAC]

This looks pretty good to me, considering the severe driving conditions. Was the T6 driven under similar conditions? Where is the AG wear coming from? I don't normally see that. Fuel% looks pretty good for your 5 mile commutes at slow speeds to work under frigid conditions. That's a lose/lose situation even under warm climate conditions. It handled the 7.5K OCI just fine...no engine damage.

 

[demarpaint]

My monitor sucks, but if I'm seeing this correctly, the interval was only 6 months, and 7,477 miles? If so I would not follow Amsoil's severe service recommendation of 1 year or 15,000 miles, you'd be asking for trouble. OTOH you changed it at the right time if the oil was in use for 1 year. Then the oil held up as Amsoil claims.

 

[dparm]

270 flash point? Yikes.

 

[Gene K]

I dont know how much faith I would put in that 1.73 Fuel Number. That looks like a good bit more fuel than that. The fuel looks to me like its starting to attack the oil and bearings to me.

Is it enough to cause damage? I dont know but I do know if I saw numbers like that after 30,000 miles on one of my diesels I would be concerned.

 

[oggb]

The type of driving you're describing sounds more like severe service. Follow the severe service interval (3750 miles) and use Rotella T6 or T5 and be done with it. It's really that simple. I do 4500 mile intervals on my WRX using Rotella T5 or T6 in the winter and whatever 15w-40 HDEO is cheap during the summer.

Want to know what these engines can take? Mine ingested dirt from a loose intake plumbing connection for the first 60,000 miles of its life. I took the intercooler off and cleaned it out with gasoline and it looked like mud pouring out of it. My car still runs perfectly fine and burns virtually no oil (aside from Mobil 1/Pennzoil Platinum) and I drive the [censored] out of it.

As for the fuel dilution - did you take the car on a sufficiently long drive before sampling?

 

[Turbofig]

I think I would stick with the t6 even though all miles driven were not the same I really believe amsoil's major push is extended intervals and with a performance car such as an STI your more concerned about performance inmo. The t6 is hard to beat for price just comparing the addative packs of the two I would much rather see t6 in my engine.

 

[OldCowboy]

This driving pattern is one of the classic definitions of "severe service." Frequent short trips which don't allow the oil to come up to operating temperature. Numerous cold starts when the oil is thick and doesn't pump well. The TBN of 2.8 shows the additive package is getting used up.

The bottom line: You doubled the severe service recommended mileage without damage and with some additive package remaining. It's a good thing you were using an oil with a starting TBN of 12.6. If you'd been using some of the other premium full synthetics which have a starting TBN in the 8-9 range you probably would have completely exhausted the additives and would have seen significantly increased wear numbers.

Actually, if this had been Rotella T-6, with its starting TBN of 10.6, you would have totally exhausted the oil.

 

[gathermewool]

Originally Posted By: tig1
Fuel may be the big problem here. Your FF is very low, in fact I don't remember seeing one like this. With only 40K on this engine you may need to go to 3K OCIs to make this engine last.


Fuel has been my biggest issue so far. For all of my Dyson analyses, except for the last, fuel has been > 1%. What may be the issue is the off-the-shelf map that I’m running. The stock map doesn’t drop AFR’s down substantially until well after the onset of boost, most likely for emissions reasons. Cobb’s map drops AFR’s down to 11:1 immediately, which could be (read: probably is) the source of my dilution. The strange thing here is that I changed my oil the day after driving 65 mph all the way down from Boston to New London without boosting at all. Part of the fun of the off-the-shelf map is that it comes with boost-select for the SI-drive system. I selected the mode with lowest throttle input and target boost, which consequently left me in vacuum (and higher AFR’s) for the duration of my trip down and while driving to the hobby shop to change my oil.

This report shows that I can’t take Amsoil (at least the SSO 0W-30 flavor) nor T6 out this far and have it hold up. I tried the same with T6, as shown above, and it was beat all to heck, too. As soon as I backed down to ~5,169 miles with T6 all was well, and I experienced the lowest fuel dilution so far.

My guess is that extended drains MAY be possible during warmer months, but are darned near impossible (at least with these two oils) during the colder, fuel-diluting months…maybe not, and maybe I’ll end all of this UOA shenanigans and stick with T6 at 4-5k intervals with nary a worry.


Originally Posted By: INDYMAC
This looks pretty good to me, considering the severe driving conditions. Was the T6 driven under similar conditions? Where is the AG wear coming from? I don't normally see that. Fuel% looks pretty good for your 5 mile commutes at slow speeds to work under frigid conditions. That's a lose/lose situation even under warm climate conditions. It handled the 7.5K OCI just fine...no engine damage.


I agree with the no engine damage assessment, though I’m still going to back this next interval down to 5,000 miles, even though it should be better with all of the warm-weather driving. It seems like such a waste to drain Amsoil so soon, but all well. The T6 represents all of the previous samples except for the very first one, which was Cam2 5W-30. That’s on the above set of UOA, and you can follow it by date and mileage.


Originally Posted By: demarpaint
My monitor sucks, but if I'm seeing this correctly, the interval was only 6 months, and 7,477 miles? If so I would not follow Amsoil's severe service recommendation of 1 year or 15,000 miles, you'd be asking for trouble. OTOH you changed it at the right time if the oil was in use for 1 year. Then the oil held up as Amsoil claims.


6 months is correct. I meant to change it at 6,500 miles, but got extremely busy.




Originally Posted By: dparm
270 flash point? Yikes.


I saw that, too. That’s worse than the worst T6 showing. However, this is the worst weather (winter) the STI has been through, being only its second winter as a DD. The first one it stayed parked while I drove my old Legacy. Unfortunately, I ended up giving my DD away to a relative who smashed her car, so the STI became my DD.


Originally Posted By: Gene K
I dont know how much faith I would put in that 1.73 Fuel Number. That looks like a good bit more fuel than that. The fuel looks to me like its starting to attack the oil and bearings to me.

Is it enough to cause damage? I dont know but I do know if I saw numbers like that after 30,000 miles on one of my diesels I would be concerned.


What do you mean? You don’t trust the number itself or having such high fuel dilution in the sump? The numbers shown here, at these levels, don’t concern me at all. I’m not going to say that the results were good, nor that I plan to run it this long again, but I don’t believe that my engine has suffered.

Besides, Subaru says it’s ok to run 7,500 mile OCI’s using synthetic oil. What do you guys think about that? Ha!

Oh, and thanks for all of your comments every one. It may seem like I'm pretty set in my ways when it comes to wanting to extend my drains, but I'm very appreciative of all your input and advice.

 

[demarpaint]

Thanks for clearing it up for me, I did see 6 months then. Amsoil had a severe service rating of 1 year of 17,500 miles IIRC. AZO is 1 year or 15,000 miles. In either case I would not follow Amsoil's SS recommendation in this application. This has always been an issue with me with extended drains, one size clearly doesn't fit all engines and applications.

Good thing you didn't go the full year, or 15K! I'd follow Subaru's recommendation for severe service and play it safe with PP, PU, M1, or Edge. JMO

 

[gathermewool]

Originally Posted By: demarpaint
Thanks for clearing it up for me, I did see 6 months then. Amsoil had a severe service rating of 1 year of 17,500 miles IIRC. AZO is 1 year or 15,000 miles. In either case I would not follow Amsoil's SS recommendation in this application. This has always been an issue with me with extended drains, one size clearly doesn't fit all engines and applications.

Good thing you didn't go the full year, or 15K! I'd follow Subaru's recommendation for severe service and play it safe with PP, PU, M1, or Edge. JMO


I agree. I didn't intend to take it past 6,500 miles, but was on travel for a week which required a lot of driving. The interval being six months was merely a coincidence.

My intention is to try RLI 5W-40 HD for the next two intervals, and to hopefully be able to take it out past 10kmi eventually. If RLI doesn't prove to be up to the challenge I'll stick with T6 at 4-5k intervals with UOA every third OCI or so.

FWIW, the want for extended drains and UOA is purely for entertainment value and to maybe get some of the STI guys to realize that > 3k intervals are very doable.

 

[demarpaint]

You are certainly going about it the right way! Keep up the good work, and the updates!

 

[Pablo]

Originally Posted By: demarpaint
I'd follow Subaru's recommendation for severe service and play it safe with PP, PU, M1, or Edge. JMO


Or just use Amsoil OE or XL.

Fuel dilution is pretty huge here. Maybe find the root cause.

 

[Steve S]

Originally Posted By: demarpaint
My monitor sucks, but if I'm seeing this correctly, the interval was only 6 months, and 7,477 miles? If so I would not follow Amsoil's severe service recommendation of 1 year or 15,000 miles, you'd be asking for trouble. OTOH you changed it at the right time if the oil was in use for 1 year. Then the oil held up as Amsoil claims.
Amsoils claims are for a mechanically sound engine. If the fuel is too high then the miles time up to claim may not be valid.

 

[INDYMAC]

Originally Posted By: Pablo
Originally Posted By: demarpaint
I'd follow Subaru's recommendation for severe service and play it safe with PP, PU, M1, or Edge. JMO


Or just use Amsoil OE or XL.

Fuel dilution is pretty huge here. Maybe find the root cause.


The root cause has already been identified. He needs to move further away from work and move to a warmer climate. 1.73% fuel on a Dyson report is fleet average on mechanically sound engines, from what I've seen. So he did pretty well considering his driving style and environment. The SSO worked well and it should again on this fill.

 

[bluesubie]

Didn't I caution you not to go far on SSO.

As for the extended interval comments, Amsoil does not recommend exceeding 3,750 miles with any of their oils in this car. Good oil, but maybe not the best choice for this application. The fuel is probably from the Cobb Off The Shelf map but you know that.

In regard to the new 7,500 mile intervals for 2011's, someone at nasioc spotted some changes in the FSM.

Quote:

C: OIL PIPE
• A dedicated turbo oil supply pipe (circuit) has been adopted.
The use in existing models of a common pipe (with filter) for both the OCV and turbo oil supply pipes, has been changed with adoption of a dedicated turbo oil supply pipe (circuit).

D: AVCS PIPE (RH)
The AVCS pipe (RH) has been changed in order to improve turbo quality.



-Dennis

 

[demarpaint]

Can we really blame the engine for the fuel dilution? Or could it be the type of service, climate, engine design, and/or conditions? My point is one size doesn't fit all, this car proved it. W/O a UOA following Amsoil's recommendations this engine would have lived a short life. More frequent shorter OCI's would be my recommendation with a less expensive oil. My point is SSO would not have made a year, or 17,500 miles under those conditions.

Are we saying here this engine is not mechanically sound? It could be a sound engine just not getting up to temp during the cold winter time, and requires more frequent oil changes. JMO

 

[Pablo]

Originally Posted By: demarpaint
Can we really blame the engine for the fuel dilution? Or could it be the type of service, climate, engine design, and/or conditions? My point is one size doesn't fit all, this car proved it. W/O a UOA following Amsoil's recommendations this engine would have lived a short life. More frequent shorter OCI's would be my recommendation with a less expensive oil. My point is SSO would not have made a year, or 17,500 miles under those conditions.


Your point is the usual. Amsoil does NOT recommend "one size doesn't fit all". In your quest to prove your point your sorta missed bluesubie's post.

Example:

http://www.amsoil.com/mygarage/vehiclelookup.aspx?url2=2008+SUBARU+IMPREZA+F

 

[duaneb9729]

Wasn't the MAF changed and suspect? Or did I miss read that ?