|
Well, apparently a lot of the concerns over cold viscosity come down to how many cold starts that you do. I estimate that my car goes through less than 100 cold starts per year and maybe 400 hot starts per year.
At this rate, Mr. Raby's test could represent over 10 years of service from my motor. Obviously if you are using your car as a daily driver, it is a totally different application, with different concerns.
Just a couple of other random thoughts:
From the data that I have seen in the past, the API specifications on oil viscosity are rather loose. That is you can have a 10 weight oil from two different sources that have a very different kinematic viscosity, and still meet the API's broad definition of "10 W".
It seems that a lot of engine manufacturer's are basically using the lubricating oil as control oil for cam timing systems, and even cylinder shut down systems. I believe that they need rather low viscosity oil for some of these system to function correctly.
Some manufacturers would sell their soul for another 0.1 mpg benefit to meet the government CAFE requirements.
All of this seems to keep driving to lower viscosities.
__________________
Kippis
986S
991S
Van Diemen RF97
|