I stopped using it in Germany about 1993 because i was running $100 a gallon Castrol RS 10w60 (the red oil).
In the US i used it again in 06 or so because i figured the Americans were running inferior Gp III synthetics and it could use a little help.
Then i joined BITOG and learned something. The MoS2 was doing nothing at all, no better fuel economy no better compression (actual before and after 2,500 readings, nothing detectable by the butt dyno.
That car sat for over a year then i pulled the pan (it was rusting) and there it was, right on the bottom of the pan.
That was the last time i touched the stuff and never will again.
There is no significant plating action on bearings with Mos2. AFAIK you cannot deposit a solid onto an oil covered surface. Try it sometime.
Why would you need to, the oil film keeps the crank from hitting the bearings, if it didn't the bearing would be damaged in seconds.
So you contend it makes the oil slippier? Well if thats the case what is going on with the needle bearings in the roller lifers, cam followers, thrust bearings, etc? How slippy can it be before they start skidding?
I am not talking about micro movement but fully loaded rotating needle bearings, something that wasn't found in old school engines. I don't know the answer but i know it is a concern.
Engines today cost a small fortune, why risk a good engine on a $10 can of whatever especially when the engine manufacturer and the oil producer both don't authorize or recommend it.
Originally Posted By: Koyo Torrington
LUBRICANT ADDITIVES
Additives are materials, usually chemicals, that improve specifi c
properties when added to lubricants. Additives, when properly
formulated into a lubricant, can increase lubricant life, provide
greater resistance to corrosion, increase load-carrying capacity
and enhance other properties. Additives are very complex and
should not be added indiscriminately to lubricants as a cure-all for
all lubrication problems
http://www.koyousa.com/brochures/pdfs/catb2016e-4.pdf