Terry does not use Blackstone (apparently, the swear filter blocks B.S., minus the . .'s), and his lab is not in TX. If you send your sample to Blackstone, the difference between the $99 and what Blackstone charges is what goes to Terry for the interpretation. This is assuming that you sent your sample to Blackstone because you trust their analysis, but want his interpretation of the results. When you send the sample to Terry, you're sending the sample to a lab he trusts.
I've asked him who he uses. He wouldn't tell me the name of the lab since he says they don't do public analysis. He informed me that what they do is different - he says more accurate, but I wouldn't know - than what Blackstone does.
I'm of the opinion that sending in samples of the same oil to the same lab will provide the best results. I'm not sure how often labs obtain new equipment, but I'm sure the testing methods and procedures would remain the same, and results should be consistent, regardless of their deviation from what the most accurate results might be.
As most who truly understand the value of UOA say, -smarter guys than me, I'm sure - UOA are mostly beneficial for obtaining a snapshot of the condition of the oil, and how things stand thus far in the OCI. To say that an oil went from a TBN of 8 down to 4 over 4kmi, and assume that it will linearly degrade to 2 over the next 2kmi is silly. As was stated before, assuming that an oil with a higher TBN will perform better is also foolish. I can't even begin to interpret the results of an oil analysis other than to say, "oh, look at that TBN and TAN. They look...good. My, those additive numbers look pretty robust, too." If some one asked me what I meant by good, I'd be at a loss for words. I could state the google definition of the acronyms, and a basic explanation of what each is, but to give an accurate depiction of their interactions and what they signify is beyond me and, from what I've read, beyond most people who comment on the UOA side of the forums. While I, like most, crave attention to my UOA report, I take what every one says here with a grain of salt.
I'm sorry to the OP for jacking your thread. Based simply on the numbers I would assume that the two labs who were closest give a more accurate indication than Blackstone. Blackstone may be using equipment with lesser resolution. Who knows. Have you brought the discrepancy to their attention? I would assume they get a lot of business here, and what you've showed will turn a few people away from their services. It would behoove them to solve he mystery and satisfy your curiosity.
