http://www.exxonmobil.com/UK-English/Basestocks/PDS/GLXXENBSKEMVisom.aspx
Here is a spec sheet for Visom, a very high grade Group III+ used by XOM. It has been said by XOM that using this base oil along with some PAO and other group V base oils (AN's/Esters) that the performance matches an all PAO formulation.
I assume Visom is found in many M1 formulations and in different amounts based on the desired performance of the end product. A Mobil PDF posted awhile back confirmed this. Blends obviously change over time so that always has to be kept in mind.
They do seem to have an excellent viscosity-volatility relationship.
Here is a spec sheet for Visom, a very high grade Group III+ used by XOM. It has been said by XOM that using this base oil along with some PAO and other group V base oils (AN's/Esters) that the performance matches an all PAO formulation.
I assume Visom is found in many M1 formulations and in different amounts based on the desired performance of the end product. A Mobil PDF posted awhile back confirmed this. Blends obviously change over time so that always has to be kept in mind.
They do seem to have an excellent viscosity-volatility relationship.