Amsoil 0w20 SP - Kurt Orbahn Shear Stability

[buster]

From Russia with Love. Amsoil 0w20 SP subjected to the d7109. If I'm reading this right, after 90 cycles the kv 100C went from 8.92 to 8.69, which is an excellent result.

https://www.astm.org/d7109-22.html
https://www.savantlab.com/testing-highlights/testing-shear-stability-and-viscosity-loss/


"This test method is not intended to predict viscosity loss in field service in different field equipment under widely varying operating conditions, which may cause lubricant viscosity to change due to thermal and oxidative changes, as well as by the mechanical shearing of polymer. However, when the field service conditions, primarily or exclusively, result in the degradation of polymer by mechanical shearing, there may be a correlation between the results from this test method and results from the field."

 

[FowVay]

It says viscosity loss of 2.6% after 90 passes. That's amazing.

I remember reading some data from Valvoline on their motorcycle oils. A requirement for the JASO MA specification for the oils to stay in grade after 30 passes through the Bosch diesel injector (shear test). The Valvoline 10W-40 motorcycle oil passed the JASO requirement but it sheared out of grade on the 31st pass. AMAZING. This is when I learned that meeting specification or exceeding specification has true value and meaning.

 

[kschachn]

Good mechanical shear stability would be due to either high quality VM or a lack thereof since oil molecules aren’t going to shear. A 0W-20 with good base stocks wouldn’t require much VM and I suspect that contributes to the stability.

 

[ltslimjim]

The viscosity index basically didn’t move either. Though, I’m not sure if the test method has as much a meaningful impact on the VII when looking at operating viscosity?

 

[kschachn]

It says viscosity loss of 2.6% after 90 passes. That's amazing.

I remember reading some data from Valvoline on their motorcycle oils. A requirement for the JASO MA specification for the oils to stay in grade after 30 passes through the Bosch diesel injector (shear test). The Valvoline 10W-40 motorcycle oil passed the JASO requirement but it sheared out of grade on the 31st pass. AMAZING. This is when I learned that meeting specification or exceeding specification has true value and meaning.

10W-40 is an entirely different beast compared to a 0W-20 and not just because of the viscosity.

 

[The Lube Guy]

For those who can't read Cyrillic or understand Russian: