Link -Chevron Phillips
This is from CPChem FAQ on PAO. There is supposed to be a chart in between paragraphs but it wouldn't show up. Link will show it.This site is primarily for producers has some decent info compared to most.
Q: Has the quality of Group III base oils achieved equality with PAOs?
A: Group III mineral oils and Group IV PAOs are not of the same quality. Some properties such as Viscosity Index (VI) or °C viscosity can approach those of polyalphaolefins. However, Group III base stocks are derived from multiple feedstock choices and processing technologies, which create variability in the properties. PAOs on the other hand, are derived from a clearly defined processing technology using petrochemically pure alpha olefins. So, whether used for gear or engine oils, PAOs provide more consistent properties and a level of purity not available from other base oil groups. The uniquely beneficial quality of PAOs has been demonstrated in a series of European engine tests. Three stringent test standards required by Volkswagen and Mercedes Benz engines show the impact of the variability of Group III oils:
These data illustrate lot-to-lot variability which has been recognized for the Group III oils. While one lot of Group IIIA mineral oil passed this battery of tests, it is quite different from the quality of the other Group III stocks. Group IIIB was unable to consistently pass the TDI or M111 tests. Furthermore, the arbitrary distinction of 120 VI between Group II and III oils makes the quality requirements even more confusing. For instance, many producers have tailored production to “Group II+” stocks at 118-119 VI, just below the ambiguous Group III limit of 120VI. The VI of PAOs typically only varies one to two points. This is one clear benefit of using a carefully designed base oil. With today’s oils requiring a higher quality lubricant basestock to meet more stringent tests, polyalphaolefins are perfectly tailored and consistently manufactured to meet the challenge.
This is from CPChem FAQ on PAO. There is supposed to be a chart in between paragraphs but it wouldn't show up. Link will show it.This site is primarily for producers has some decent info compared to most.
Q: Has the quality of Group III base oils achieved equality with PAOs?
A: Group III mineral oils and Group IV PAOs are not of the same quality. Some properties such as Viscosity Index (VI) or °C viscosity can approach those of polyalphaolefins. However, Group III base stocks are derived from multiple feedstock choices and processing technologies, which create variability in the properties. PAOs on the other hand, are derived from a clearly defined processing technology using petrochemically pure alpha olefins. So, whether used for gear or engine oils, PAOs provide more consistent properties and a level of purity not available from other base oil groups. The uniquely beneficial quality of PAOs has been demonstrated in a series of European engine tests. Three stringent test standards required by Volkswagen and Mercedes Benz engines show the impact of the variability of Group III oils:
These data illustrate lot-to-lot variability which has been recognized for the Group III oils. While one lot of Group IIIA mineral oil passed this battery of tests, it is quite different from the quality of the other Group III stocks. Group IIIB was unable to consistently pass the TDI or M111 tests. Furthermore, the arbitrary distinction of 120 VI between Group II and III oils makes the quality requirements even more confusing. For instance, many producers have tailored production to “Group II+” stocks at 118-119 VI, just below the ambiguous Group III limit of 120VI. The VI of PAOs typically only varies one to two points. This is one clear benefit of using a carefully designed base oil. With today’s oils requiring a higher quality lubricant basestock to meet more stringent tests, polyalphaolefins are perfectly tailored and consistently manufactured to meet the challenge.
