Originally Posted by oil_film_movies
Originally Posted by Danh
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Originally Posted by dave1251
Originally Posted by oil_film_movies
Instead of refilling with more 5w30 alone, fight the fuel dilution the best you can by filling to the Add line with 5w30, then put in 1 pint of Schaeffer Moly EP #132, an oil thickener made out of decent base oils and a little antimony, other stuff I can't remember from some old analyses I saw. Amazon.com it.
Either that or put in 3 quarts Mobil1 5w30 with 1 quart of Mobil1 15w50, do not fill above about halfway between Add & Full lines.
We can debate how much fuel dilution there is. The 6.7 kv100 is getting too low. Good iron ppm anyway, not bad.
You contradicted your post by stating its too low but the wear metals are not out of line. Did you design and test the engine thus have knowledge what viscosity is too low to protect the engine during operation?
Well, Ford specs a 5w-30 for this engine and this sample is not even a 20-weight. So if Ford thinks a 5w-30 is needed a sub-20 weight may not be optimal.
Yes, dave1251 is confused. The way HTHS correlates with engine wear, there is a cliff it falls off of. Non-linear, very.
Get HTHS too low, and wear increases dramatically at some point.
And yes, Ford specs HTHS 3.0 (approximately), which tells us Ford isn't comfortable going down much lower than that.
For this ecoboost, add a little more hard driving, with some hot weather potentially, and that fuel dilution can then cause a lot of extra wear.
Margin is important.
Rings appear to be the most sensitive though.
See the graph below, telling the story of Stribeck Curve physics:
From another thread recently:
Originally Posted by ZeeOSix
...... increased wear can occur for oils that are less than 2.6 HTHS when oil temperature gets elevated some. But it also says if you are using a 20 wt you really have no headroom, but are right at the verge of having more engine wear is the oil temps start to rise above "normal".
You throwing your unverified theory and hope it sticks. There is nothing in this which verifies your bias any additional wear is observed on this engine with a 20 grade oil.