Wasn’t sure of the best place for this topic. Since it isn’t an actual UOA, I elected not to place it there. I’m not trying to start a fight, but I have several honest questions and concerns about the usefulness of UOAs in comparing the effectiveness of oils and their relationship to engine longevity. Perhaps someone here with more experience in this area can enlighten me. 1) According to most of the responses, It seems most of the UOAs posted in the UOA section are considered “good”. Could someone point me to a couple of bad UOAs so I know what to look for? 2) It seems that great stock is placed on trace metals in UOAs. Is there good correlation between trace metals in UOAs and engine life/longevity? In other words, if oil A shows one half the trace metals in a UOA as oil B, has it been demonstrated that using oil A will lead to significantly greater engine life? 3) There would seem to be many factors that can affect the levels of trace metals in a UOA. Driving style, temperature, driving conditions, fuel used, oil filter, air filter, engine condition, frequency of operation, and the number of “cold” starts, in addition to the oil used. My concern is that there could be too many variables present to make meaningful comparisons between UOAs between different vehicles with different drivers. Yet, in many cases, this is done in an attempt to recommend or select a “good” oil. 4) I suppose if one were careful, they could try to minimize the differences in the variables listed above and, over the course of several years, run UOAs on several oils and perhaps draw some meaningful conclusions about which oil protects their engine the best. But by that time, the car (though perhaps not the engine) might be half worn out, and the results would only apply to that vehicle. It’s also possible that by the time the comparison is finished the oil showing the best UOAs has had a change in formulation.