Valvoline Group 4 PAO?

[melk]

Aren’t high concentrations of PAO tough on elastomers and seals and must be tempered with other chemistries.

In other words PAO does have benefits but must be properly balanced. It’s not as straightforward as “more PAO is inherently better”

 

[kschachn]

Aren’t high concentrations of PAO tough on elastomers and seals and must be tempered with other chemistries.

In other words PAO does have benefits but must be properly balanced. It’s not as straightforward as “more PAO is inherently better”

That is generally true in a fully-formulated motor oil however. It still has superior oxidation resistance and cold-weather performance, plus less deposit formation.