Originally Posted By: StevieC
He mentioned Terry, it was understood that he would be doing the interpretation of the report.
Yes, he did, I missed that on the first pass, my apologies. In that context, he's getting far more out of the UOA (at much greater cost mind you) than most on this board.
Originally Posted By: StevieC
As for your other points I was defining how UOA's could tell a story which is what you were questioning. There are many stories they can tell those were just mine.
Yes, in the context of inexpensive Blackstone UOA's posted on BITOG, which I think you must acknowledge varies significantly from professional interpretation.
Originally Posted By: StevieC
Excessive metals indicating premature and badly wearing Journal Bearings and ring wear. Clearly evident by the elevated levels of high double digits like in the 55-70ppm range that a Starbucks employee could see didn't make sense compared to universal averages.
Right, but that's not what you are going to see running oil "A" and oil "B". That's what you'll see if you have a legitimate issue regardless of the lubricant in service, provided that the product is appropriate for the application. And even then, there are cases where UOA's fail to provide evidence of impending failure.
Originally Posted By: StevieC
Further if you run Oil "A" and Oil "B" a few runs each and see decreases in wear metals or the TBN/TAN not as affected or affected far too much you can hypothesize that the oil is doing a better job over the other and depending on what you are looking at make a call about how it's performing in your engine. It's not 100% scientific but it's a good indicator for those that don't want to pay for properly calibrated labs and interpretation. If you argue with this point then they might as well shut down the whole UOA section at BITOG.
I'm definitely going to argue with that point because the PPM variance between those runs is often so minute that it can be chalked up to lab variance or within the margin of error. That discussion has evolved significantly in your absence, hence my linking to Doug's article which deals specifically with UOA's that are typical as to what is posted on BITOG and generally come from Blackstone. If you haven't read it, give it a going over.
Dave Newton also wrote a few that are linked on the front page about UOA "normalization" and interpretation. They are also worth a read.
Chasing single-digit wear metals between approved lubricants is a fools errand that incurs unnecessary expense. Your typical passenger vehicle will likely be taken out by rust, accident or some other mechanical failure like a transmission going out before the engine fails. Even if the engine DOES fail, it generally isn't due to something that could be prevented from running a different oil, as your experience with your former Hyundai demonstrates quite aptly. There wasn't a Unicorn Sauce in the world that could have stopped that camshaft failure, and your oil analysis didn't predict it. You also mentioned you were concerned about the transmission health near the end.
If you are running an OTR truck for millions of miles and an engine job is 35 grand, doing a periodic sample to confirm it isn't munching coolant, an injector isn't tanking or something along those lines is logical, particularly when viewed in the context of the value of the equipment. Same thing for big industrial gensets and the like, which get periodically sampled. Jim Bob and his Nissan Sentra spending 20 bucks an oil change on having his oil analyzed so he can chase 5ppm of Fe over a breadth of appropriate lubricants isn't going to result in his engine lasting any longer, it is just going to result in him spending far more money than necessary on a piece of equipment that won't be worth any more in the end than if he just changed the oil at the recommended interval using an appropriate approved product.
Now, that's not to say running a periodic analysis to determine if one can safely run a lube longer isn't appropriate, it is. Same with your previous examples, which were all legitimate single-instance uses of the procedure, not chasing PPM variances between GTX and VWB. If you think you might have an internal coolant leak, a UOA is a solid choice. If you think you have an air intake tract leak, again, a UOA is a solid choice. If you question the health of an engine in a vehicle one is considering buying, yet again, a UOA is a reasonable choice. These are all valid reasons, which you gave examples of, for using UOA's. It is the chasing of insignificant wear metal variations between different lubricants that I, and others, have issue with, because there's really no end game, it is just an utter waste of money, money that could be spent just changing the oil, buying better filters, better tires....etc.
