SuperTech Synthetic Blend 5W-30 3.3k miles / 2008 Subaru Forester X 2.5L 134k miles

[ZeeOSix]

How have you been able to determine there’s no correlation?

If you look at all the UOAs in this forum that have an ISO particle count, and compare PC data to the "Insolubles %" data, there really isn't a solid correlation. An accurate PC is what's really needed to determine how well an oil filter is keeping the oil clean.

UOA "Insolubles %" vs ISO Particle Count

Many times someone will say ... "Hey, the oil filter must have been doing a good job because the UOA "Insolubles %" was low". But it's also been mentioned that the "Insolubles %" is an insensitive and bad parameter to measure the oil cleanliness to reflect oil filtering effectiveness. So I went...

bobistheoilguy.com

 

[Soobs]

If you look at all the UOAs in this forum that have an ISO particle count, and compare PC data to the "Insolubles %" data, there really isn't a solid correlation. An accurate PC is what's really needed to determine how well an oil filter is keeping the oil clean.

UOA "Insolubles %" vs ISO Particle Count

Many times someone will say ... "Hey, the oil filter must have been doing a good job because the UOA "Insolubles %" was low". But it's also been mentioned that the "Insolubles %" is an insensitive and bad parameter to measure the oil cleanliness to reflect oil filtering effectiveness. So I went...

bobistheoilguy.com

Are there any labs using ISO particle count instead of insoluble %?

 

[ZeeOSix]

Are there any labs using ISO particle count instead of insoluble %?

Insoluble % and ISO PC are two different tests. Blackstone (and others) can do a PC test when doing a UOA, but they will charge you extra.