30w to 40w #

[Toy4x4]

What is the change point on the viscosity scale at cst 100*C where a high 30w becomes a low 40w? Example #s: 12.7 = 30w. 12.8 = 40w
Hope I got all the vocabulary right!

 

[G-MAN]

A 30 wt has a min cSt of 9.3 and a max of <12.5 at 100*C. A 40 wt has a min of 12.5 and a max of <16.3.

 

[Ken2]

http://www.lubrizol.com/ReadyReference/EngineOils/6-OilClasses/default.htm

Click on "Physical Requirements for Engine Oils"