Dont take it that I dont think you can convert... Its just that Ive seen a very common misconception that since viscosity is commonly reported at 40 and 100C, that the 40C (thinking that it is similar to 40F) is what determines the first number... Youd be suprised how often this question comes up... And I agree, pour point is nearly useless, except that a 15wt oil that has a pour point of -54 will have a much better pumpability and a lower pumpability temperature at far lower temps, and a lower pumping viscosity at the standard -20, than a dino oil of similar 15w, or even a 10w dino for that matter...

I am very dissatisfied with mobils web site at this time because, as you said, it is quite difficult to find the cold temperature propertes... In fact, I had to call them.

JMH