relationship of oil viscosity to temp?

[Pantdino]

What is the relationship between temp and viscosity for a multi-grade oil? Specifically, is it roughly linear from a moderate temp to 100*C? So if you have the cSt for a given oil at 40 and 100 *C, can you extrapolate down to 50*F and estimate what it would be at say 80*C and 140*C?

Thanks!

 

[Jay]

The relationship is non-linear and it's a fairly complex equation. Use this calculator to find viscosity at a certain temp.