Originally Posted by SonofJoe
Originally Posted by oil_film_movies
Or, maybe the long-time Schaeffer approach will become more common. "Synergistic lubricant additives of antimony thioantimonate and molybdenum disulfide" --
https://patents.google.com/patent/US4557839 , if that is the form and IP Schaeffer uses... .
First, despite the fancy name, this is in essence Antimony Sulphide & analogous to Moly & Tungsten sulphides. That means it's a black, discolouring, powdered solid & therefore taboo in any mainstream motor oil (oil solubility & clarity is a must!).
Originally Posted by nap
Originally Posted by oil_film_movies
"
high molybdenum
(LPHM) and ashless antiwear additives technologies
offer "step out" performance benefits for fuel
economy, wear prevention, deposit control ."
Not really.... Nowhere does the paper say that by just adding moly to a thin oil you can match the properties of a thicker one (which is the question that the OP asked, and the thread's title). The claim in the paper is just that the moly has benefits.
You're not seeing the forest for the trees. In an engine & at any given condition, a certain % is hydrodynamic and it's zero wear there. The other part is boundary (scraping together) conditions. With lower viscosity, a greater % is boundary. Sounds bad, right? And that's what confuses a lot of people as they only see that "tree". .... However, as the paper is saying, increased attention to boundary conditions via moly or whatever, even when a higher % of surfaces are boundary as in when using lower viscosity, the overall ("forest") actually can achieve less or equal wear compared to higher viscosity oils since boundary conditions are handled better using surface active additives. Also, low temperature flow of lower viscosity oils reduce wear more than thicker oils, again part of the big picture, the overall effect.
I imagine these same sorts of whiners and naysayers were objecting when thinner 10w30 oil first started to be used in the 1950's when additive (surface tribofilm) technology was just beginning to make up for what thicker oil did in the past. "
That thar 10w30 with ZDDP can't replace my 50 weight oil."-- 1953, in a garage somewhere.....