I'm still pretty new on this site so forgive me if this is repetitive. I have seen many discussion on the web on this topic and I found this report easy for my simple mind to understand. I thought I would share. http://www.jatonkam35s.com/DeuceTechnicalManuals/Diesel_fuel_additive_test.pdf

Kind of got you beat to the punch... http://articles.mopar1973man.com/general-cummins/36-fuel-system/68-hfrr-testing-of-common-diesel-fuel-additives

There is a download section here, Hawkez, please feel free to look it over. Mike has a lot of info there.Some write ups are easier to understand for one person than another, and may contain the same info.As long as it makes you one step higher in your understanding is what counts.