Originally Posted By: oil_film_movies
Originally Posted By: SonofJoe
I wonder if in the future, oils will ultra thin (KV100 around 4 to 6 cst?) but that future engines will be fitted with oil temperature controllers (a) to rapidly warm up oil from cold and (b) to prevent the oil from getting so hot that its HTHS goes below a preset value. We have knock sensors to keep combustion out of the danger zone so why not actively manage minimum viscosity?
There is an active warning that I wish all cars have. Similar to the usual oil pressure warning light, some engines use the active viscosity (pressure, RPM, and temperature estimated viscosity) OBDII test:
P1521–INCORRECT ENGINE OIL TYPE
Using the oil pressure, oil temperature and other vital engine inputs the engine computer can determine the engine oil viscosity. Incorrect viscosity will effect the operation of the variable valve timing or variable displacement actuators by delaying cylinder activation, although its also simply a test for low oil viscosity that affects bearings too.
Active control of oil temperature using oil-to-coolant heat exchangers can keep oil in a certain range. The future for all engines? Its an added expense to have this, so maybe not.
Originally Posted By: SonofJoe
Of course this would mean the OEMs would have to get off their collectively bone idle arses and actually DO something (as opposed to abdicating all responsibility for anything to do with oils to the oil companies and AddCo's).
The engine OEMs probably could keep raising the specs, like better dexos1, and like the German specs do, which effectively require long life synthetics. Maybe the future will be Mobil1 Annual Protection go mainstream and standard in owner's manuals. They do this by better anti-oxidants according to Mobil's claims and patents I've seen over the years.
Modern oils have now been stretched to cover so many extreme conditions (low temperature pumpability, high temperature bearing protection, extreme oxidation control, fuel economy, etc) that the envelope can't be extended further without genuinely risking the engine. 0W16 and 0W8 are for my money 'a bridge too far' especially when you think what a bit of fuel dilution can do to drop oil viscosity. If the OEMs want to squeeze out more fuel economy (the kind of economy that Joe Soap might actually see for themselves), then they won't do this by simply doing what they've always done. There will have to be some kind of 'physical' limit on maximum oil temperature otherwise bearing are going to fail.
It's interesting that you raise the subject of added cost because this is invariably the standard line from the OEMs. However it's funny that the OEMs always seem to be able to find money for all sorts of meaningless rubbish (soft touch dashboard fabrics, electrically heated wing mirrors with indicators lights which fold in when you turn the engine off, touchscreens, etc) yet can't find a few dollars to add an oil heater/cooler. The way I see it, such a system wouldn't really have to do that much on a day to day basis. I doubt that many oils see 150°C + temperatures in their life time.
