For all the
arguing discussion about oil on the 'Net, there is really precious little information (data) available. The only research specifically about motor oil performance in reciprocating auto engines that I am aware of was a report done by Consumer Reports some years ago. IIRC it was a 60K mile test starting with either new or rebuild engines, measured before assembly, and then installed in NYC taxis and used with various oil types and brands. The results were inconclusive: all oils seemed to perform the same.
Even if we had enough documentation on used oil analysis we still would not know how the oil was performing as a lubricant, at least beyond the obvious failure which I do not think any of us really expect. I am a fan of things like these oil reports and appreciate those who take the time to post them but no one can really judge the performance of a motor oil based on those reports.
I think what is going on is that all oil is so very good that the differences don't really show up. If someone was to use oil that was from, say, 70 years ago (before modern detergents and multi- weight technology) then I would expect to see a difference in engine lifespan and performance deterioration. Otherwise I believe we can use any / all oil available to use with confidence.
One thing I am surprised at is those of you who find the shifting of your C-14's to be good using the new Rotella synthetic 5W-40. Mine shifted like it had sand in the gearbox when Shell reformulated that stuff and I ended up going to the mineral Rotella, 15W-40 weight.
But all of this does make for an interesting thread.
Brian
Well, I do expect the Motul to perform better but time will tell. The Mobil 1 Racing 4T report posted by Joel provides some interesting comparison. Some Rotella numbers are better and some Mobil 1 numbers are better with the Mobil . I expect the Motul to be better than both. But the main point to me is that at less than half the price, my results indicate the Rotella is more than adequate for 6000 miles.