The chronology:

I sent in a virgin sample to Blackstone for the generally highly regarded Petro Canada Supreme Synthetic (in this case its 0W30 entry). Looking at the numbers I was surprised by the calcium, phosphorus and zinc...all seemed low. Blackstone was kind enough to retest...the new numbers were similar.

I contacted Petro Canada and they requested I submit a sample to them. He did tell me, prior to testing my sample, that he expected, based upon batch analysis that Calcium would be around 2230, Phosphorus 780 and Zinc 870.

I have summarized the information below. (I have a full analysis for only Blackstone and Wearcheck)

All samples were taken from the *same* bottle of new unopened oil.

Hmmm. very interesting.

Downright disturbing is what i call it.
People buy oil,switch brands,weights etc based on the numbers coming out of these labs.

I never got into doing UOA because i question the value if a UOA on a single run of a specific brand then doing another on the latest craze trying to compare the two.
Long term trends with the same product i would think may provide better results.

The way this looks it appears that some of these labs may be pulling numbers either from manufacturers spec sheets or out of their behind.

This tells me that my money is better spent changing my oil than analyzing it.

Amen. So when you look at these numbers from UOA, remeber that the standard deviations are apparently HUGE when looking at these numbers. It tells me that these numbers are virtually worthless.

FWIW I purposely did not tell Wearcheck the brand or viscosity of oil.

+1, and now with the caveat that one uses the same lab!

I wonder if additive fallout(some falling to the bottom) would cause numbers like that. I myself am no chemist and not sure if calcium itself can fall out of suspension in oil.

I promise I shook the bottle each time I drew a sample.

Now you know why I ain't doin' no UOAS.

It would sure seem that way.

Did you inform Petro what the sample was beforehand?
The numbers seem real close to what he told you they would be,
Do you get the feeling they just tweaked the numbers and actually tested nothing?

Wearcheck's numbers look spot-on. I'd believe them the most.

B/S is a a good lab, but when they shouldn't have stood by their numbers - they should have known something was off with their numbers, and investigated thoroughly.

For sure I told them as I only made contact with them because the Blackstone numbers didnt seem right...two tests in a row! So the company knew I was sending in another sample of their 0W30 from the same bottle. Of course I have no idea what was actually done with my sample but given my correspondence with their rep. I take it at face value that it was tested.

The closeness of wearcheck to petrocan would make me suspect blackstone got the test/sample mixed up on first instance and fudged the numbers the second time. Just guessing though.

+1

21Rouge, do you have the other VOA figures from Wearcheck including TBN?