I see these every so often and figured I would post mine. I guess the results kind of surprised me, as I am going on 15k mile intervals with my truck. I am kind of new to being interested in oil, so I guess this is my start.

I have owned my S2k for 8k miles, buying it at 12k, this being my second change since ownership.

I use/d Mobile 1 10w30 with the OEM filter.

 

interesting

 

considering the use that you have placed on the car and the drain interval I think it is decent. You can't compare it to a normal daily driven oil analysis, the track event and autocross events would increase wear considerably.

If it was my car and I was doing such events I would be running Redline oil during the track and autocross events for an extra margin of wear protection. It might be a bit overkill for a daily driven vehicle but when it comes to track events and autocross this oil really shines. On my older Civic I would run Redline for racing events and other oils for daily driving, my oil analyses from track events were pretty pristine with Redline oil, pretty much no increased wear as compared to daily driving miles.

 

Personally, I think that's a very good report. I really don't think 9ppm of aluminum is high. Keep in mind that your chromium is zero, and this would be elevated if you had ring wear.

I'd suggest that you get a TBN with your UOAs to give you an idea of how much life you have left in your oil. Shortening up your OCIs to lower your aluminum doesn't make sense (IMO) because the aluminum isn't doing any harm. It's elevated silicon that is abrasive.

Your low viscosity isn't a surprise. Mobil 1 is known not to be very shear stable. If it isn't giving you bad UOAs, it's not a concern but personally I'd be inclined to switch to a more shear stable oil with autocross.

Thanks for posting.

 

Thank you for the feedback. I honestly did not, nor do I consider the limited AutoX and a track day a severe beating for the car.

I have switched to Royal Purple for this change, but upon further research I will be ordering Amsoil for the next change, whenever that will be.

Where does the silicon come from? Is that a product of the oil, or wear from something internal?

I had marked the TBN box initially, then opted out of it at the last minute. I associated that with "longer interval use", which in the S's case I was not interested in. For future UOA's I will keep the box checked.

It's interesting as Mobil 1 in my truck seems to fair a lot better at 12k change of daily driving, than it did with this. I understand two different platforms, but I guess I was expecting better.

 

Silicon is also used as an anti-foam additive.
A VOA would confirm that.

The aluminum & iron could be from the valve train.
The cams run in alu "bearings".
That said: 20k miles is "just broken-in", it's most likely all normal and the "wear" will be less the next UOA.

As fas as the particles detected by UOA's are "wear".
Big chuncks are not detected by UOA's.

 

Adding to SpitfireS' comments:

Silicon levels above those seen on a VOA for that oil typically are associated with dirt ingested past the air filter. Fine particles of sand can get through, which are very abrasive. Elevated wear metals are often seen with elevated silicon levels.

silicon can also come from new seals and gaskets, so it is also common to see a blip in silicon after replacing an oilpan or other gasket, as well as on new engines,

 

Thanks, so a dirty air filter can add to that. Good to know.

 

I think a dirty filter would have to be very dirty to cause air to find a path of less resistance around the filter somewhere, resulting in unfiltered air to enter the engine. The way our filter fits so snugly to the air induction entry port, you would have to have some sort of leak in the induction plumbing down stream of the filter. It's worth investigating if you have high Si on UOA.

If you operate your car in dirty/dusty conditions, you can expect higher Si levels to accumulate in the oil. The air filter can't catch everything. That's why manufacturers recommend a severe service condition maintenance schedule (they used to anyway) for a dirty/dusty environment.

The biggest downfall when using a dirty air filter is poor fuel combustion and loss of power. High fuel dilution might indicate that you need to change the air filter.

After reviewing your UOA, you don't have high Si content and your fuel dilution based on flash point is one of the best I've seen.

The only thing that jumps out at me is the make-up oil. I rarely see an AP2 consuming any oil at all. That's something to keep an eye on and if it continues, maybe try a different oil.

Thanks for posting this UOA.

 

INDYMAC Posted on Jul 17 2010, 10:58 AM

It also makes one wonder about the 9,22 cSt.
The oil really sheared.