Cold cranking viscosity VS actual viscosity?

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211
Location
Mississauga, ON
What is the difference between the Cold Cranking apparent viscosity and the actual viscosity at the same temperature? For example: GC 0W-30 CC Viscosity @ -30C: 3200 cP Viscosity @ -30C: 6767 cSt Amsoil 0W-30 CC Viscosity @ -30C: 2993 cP Viscosity @ -30C: 3821 cSt The actual viscosity is close to double for the GC, yet the Cold Cranking viscosities are similar. Why is that?
 
Messages
700
Location
USA
Maybe one is "slipperier" than the other. Even though it is thicker, it flows better???
 
Messages
263
Location
DFW, TX
The calculated Vis is Kinematic (mm2/s) @ temp °C, while the other is Cranking (mPa.s)max at temp °C. I guess my question would be how are the two related, if at all?
 
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