Highest HTHS oils available, taking into account shear stability

[RevvCats]

But also, mechanical shear (not sheer) of the VM is highly dependent on the engine. Most engines do not place high shear loads on the oil, but some might. In those results you posted, the no-VII result shows the margin of error for the test.

He also tested a few home blended Xw-30 oils using a group 3 and PAO base along with 4 different VII. PAO/PIB resisted shear about as well as the no VII oil, but that stuff wrecked the oils winter rating.

It would be neat to see the same oil run in different engines to see if there are viscosity differences. That gets to the question of how relatable is the KRL test? If I put Mobil 1 FS 5w-50 in my mustang how quickly would I see that amount of viscosity breakdown at the track or just from daily driving?

 

[JAG]

He also tested a few home blended Xw-30 oils using a group 3 and PAO base along with 4 different VII.

Thanks for the great charts. Did the home-blended oils have a complete additive package or just base oil and VIIs?

 

[RevvCats]

Thanks for the great charts. Did the home-blended oils have a complete additive package or just base oil and VIIs?

Pretty sure it was just the base + VII since all he was looking at in that video was viscosity loss

 

[Jetronic]

But also, mechanical shear (not sheer) of the VM is highly dependent on the engine. Most engines do not place high shear loads on the oil, but some might. In those results you posted, the no-VII result shows the margin of error for the test.

They said it's the dispersants in the oil that can also shear. But there is always going to be an error in any test or measurement. I'd sign for 1% viscosity loss though.

 

[addyguy]

As mentioned, there are 70-weight racing oils that have not been considered. Kendall ‘Nitro 70’ is another one.

 

[Cujet]

If I put Mobil 1 FS 5w-50 in my mustang how quickly would I see that amount of viscosity breakdown at the track or just from daily driving?

We already know the answer. In the Ford 5.0, it shears in about 1500 miles of enthusiastic driving. Occasional track days or hard 'canyon' use. The 9.7% number above fits with what users see. If I remember correctly, there were short OCI tests that backed this up, but I can't find them at the moment. It may not matter much, as its loss in viscosity does not do more than drop it into the robust 40 viscosity range. With the above HTHS at 3.8.