SpitfireS

According to Castrol the 5W-30 Syntec
Well.. let me tell you, the ACAE spec's "All grades to stay in grade" for A5/B5 quality.
So I say: A5/B5 = "Fail"
There is no way around it.

OneSilverS2k

It is hard for me to send in lab results. I use Castrol syn edge.. The problem is I just went to tail of the dragon, High revving for two days, and the round trip was 2015 miles on the car, I lost a qt. so I had to put a qt in. Wouldn't be worth sending it in, in my case.

zeroptzero

you would be a great candidate for a UOA, I'd love to see your results. When you send in the sample you tell them how much oil was added between changes and they take that into account in their analysis. Your harder driving could be offset by the added oil so it should be a good analysis. Do it, do it, do it, do it , lol......

If you can't send it in to Blackstone, any CAT equipment dealer can usually provide you with an oil analysis bottle to submit a sample to their lab. Most cities have a CAT dealer in their area, so it is an easier supplier to find. I use them in my home town, I just buy the sample kit from the dealership and fill up the bottle and pop it in the mailbox, pre-paid.

CarbonCrew

Actually there is a way around it... ACEA dictates that the tested oil exhibits shear stability per standardized test methods ASTM D6278 or CEC L -014-93 at 100 C Viscosity after 30 cycles.

Castrol lists the 5w-30 with viscosities of 9.7 cSt @ 100C and 58.2 SUS @ 210 F. The oil shears down from 9.7 cSt to 9.18 cSt, that hardly qualifies as a 'fail'.

Bror Jace

Here's a product data sheet with the Castrol Syntec oils:

http://www.castrol.com/liveassets/bp_inter..._syntec_usa.pdf

Syntec 10W-30 starts out as a SUS of 59.6 which is already right at the bottom of the 30 weight range according to Blackstone ... whose range seems a tad high compared to the chart I have:

http://i229.photobucket.com/albums/ee149/B...ositychart3.gif

Still, the oil DID sheer/thin out of grade.

As INDYMAC points out, most mass-market PCMOs are designed to shear slightly as they are run to reduce hydrodynamic drag and enhance fuel economy. Castrol likes to market itself (especially its synthetics) as the oil for hardcore car guys but it really is just a mass market oil for street use by the average Joe. Not that there's anything wrong with that ... just don't kid yourself.

Even their Edge will thin out of grade:

http://www.bobistheoilguy.com/forums/ubbth...708#Post2044708

Also, cars with a lot of cold starts and/or short trips will have at least some fuel dilution which will drop the viscosity quickly. This can happen even when the oil report does not find significant fuel in that sample.

However, a bit of thinning does not necessarily mean increased wear, as this sample shows. Also, many cars spec'ing 5W-20 oils are producing very clean UOAs with the ultra-thin stuff.

Want a 10W-30 synthetic (blend) that will stay in grade? I think Schaeffer oils are pretty good (if you can get them in your area):

http://www.schaefferoil.com/datapdf/703.pdf

I'm using Pennzoil High Mileage Vehicle 10W-30 right now. I'm switching to Pennzoil Platinum 10W-30 this spring. If I can put 5,000 miles on it in one year, I'll do a UOA.

And yes, 5W-30 and 10W-30 should be the same viscosity at operating temp. I hate it when Blackstone's comments are off the wall like that.

All else being equal, the 5W-30 will flow better at cold temps but the 10W-30 should be a bit more shear stable due to fewer VIIs being used (but things are rarely that simple).

SpitfireS

As far as I understand ASTM, they specify the test method, not the outcome.

ACAE A1/B1 actually allows a 30 weight to shear down to 8.6 cSt.
A5/B5 does not allow a shear out of grade.
SAE J300 spec's the SAE 30 from 9.3 to 12.5 cSt.
9.18 cSt is out of grade.
Try shooting holes in that....

If anyone claims their product "exceeds" an international spec, one expects a higher quality than specified.
Castrol most likely thinks shearing down is a good quality.

Shear stable 0/5/10W-30's do exist.
This Castrol isn't one of them.

INDYMAC

There is a lot of UOA data available to evaluate how engine oils, or any lubricant for that matter, hold up under real world applications. The end result of performance often makes you scratch your head and wonder how some of these lubricants met or exceeded API, ILSAC or ACEA specs. I also wonder sometimes how products can say that their product has typical physical properties on their PDS, when they clearly don't. The best advice I can give is to "trust, but verify".

As I mentioned before, I think the limited picture this UOA paints is that 10W-30 Castrol Syntec is a great choice for this engine. How long can you use it (OCI)? There's not enough information to tell. Are there other SAE 30 grade engine oils that are more shear stable? Yes. Do you need them? Probably not. Maybe the next time you test a sample you can ask Blackstone to do more tests if you can afford it. If you have them test for TBN and TAN, it will cost $20 more. Or you can just jump up to a Dyson Raw Data analysis for $59 and get every bit of information you need to evaluate the condition of the oil.

CarbonCrew

You are correct, 9.18 cSt is out of grade. However, ACEA sequences does not apply the "Stable, stay-in-grade oil" stamp to oils that have been run through an engine for 5000 miles. That's all the wiggle room that Castrol requires to fire up their marketing engine and claim, correctly, that their oil 'meets or exceeds' A5 sequences.

Furthermore, ASTM D6278 goes on to explicate their test method with the following statement:

"This test method is not intended to predict viscosity loss
in field service in different field equipment under widely
varying operating conditions, which may cause lubricant viscosity
to change due to thermal and oxidative changes as well
as by the mechanical shearing of polymer."

However, that is not to imply that there are no correlations to be drawn between ASTM D6278 data and field data.

INDYMAC

After reviewing this report again, I just noticed that 6 ppm of Tin were identified. I don't know what this is coming from, but I've never seen it on a S2000 engine UOA before. Something to keep an eye on I guess. It might just be organic contamination of the virgin oil.

SpitfireS

CarbonCrew Posted on Oct 14 2010, 12:45 PM
You're right
I guess I got a little carried away....

Btw.. how does one exceed a A5/B5 stay-in-grade spec?
The more you try to shear it, the more shear stable it becomes?