Originally Posted By: SEMI_287
I believe it's mostly synthetic. Quoted from the MSDS "Synthetic base oil and additives. The highly refined mineral oil is only present as additive diluent."
The flash point may be good, but the pour point does not indicate much synthetic at all. Plenty of conventionals have lower pour points. Mostly synthetic? I highly doubt it. The MSDS does not have to be accurate in that respect. Consider what the MSDS is for. Dealing with a spill or fire with oil is the same whether it's Group I, II, III, or IV, and they have similar safety issues with skin contact.
Where they get picky on an MSDS is, for example, if a compressed LPG tank were labelled as compressed carbon dioxide, or anhydrous ammonia convoluted with natural gas, or ethanol versus hydrochloric acid.
Originally Posted By: dparm
Odd that the 10w40 is API SN.
Since 10w-40 isn't a resource conserving grade, I'm really not surprised.