2017 Focus RS - Castrol 0W40 - 4,900 miles

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Jan 14, 2015
Latest UOA. Oil filter used was a Ford Motocraft FL910s. This sample saw 2 auto-x days and some very hot summer temps. Oil replaced with more Castrol Edge 0W40, as it seems to be getting the job done for me, is cheap and easy to find, and is producing good results. I would run a longer OCI but wouldn't want the oil to shear down any further.. Curious to get other opinions as well. Thanks
I'm not sure I would run a longer OCI either. You might want to pay for TAN next time, too, if you are concerned about change intervals and the low flashpoint. What sort of oil life meter does the car have? What oil is it spec'd for?
It's probably still breaking in / washing out particles, so it's hard to say but based on the fuel content and flashpoint, I'd say you ran it too far. I would have sampled at 3k to see how it's doing... which is what you should do next time.
I would ask to rerun test: I don't believe in TBN=7 after almost 5k miles in a turbo engine. Pretty sure that this is a lab error.
I believe the TBN. From all the UOA's I have seen, Edge 0w40 will do 10k standing on it's head in most applications. It is likely a 12 to 15k oil in lot of rides. But NOT this one with the fuel dilution issue. Blackstone is notorious for under evaluating fuel, so if they say 1.3 it's likely a LOT higher.
360 means you're likely at 5-6%. I'd put a nicer oil in such a nice car. An off the shelf oil does this [censored] car no justice.
Last time I saw 1.3% FD from Blackstone the back to back GC reading was 7.8%. Knowing Blackstone isn't wrong, they just use an outdated test, in the long run this is going to be your engine corroding away.So I did a study with a major GT-R power house. I can't name due to an NDA and they didn't want other tuning houses to see the results. Anyways, we ran oils on 400WHP, 800WHP, 1600WHP and 2000WHP vehicles. Turbo and N/A. The difference between new oils, one in particular, Amsoil vs. RLI, was 6whp on the 400WHP N/A car. You don't even want to know the differences between valvoline and M1 vs. Amsoil/RLI were let alone on the more powerful turbo cars. We retested the vehicles once they had put miles on them and the differences between an oil at 5,000 miles with 4% FD and one with 1%FD was over 15hp. Tests were conducted in a climate and humidity controlled environment, so no reproduction issues here.
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