Hello All,

This is my first post to a forum ever. I have received so much help from these forums that I finally decided to join.

Question; I have been using Royal Purple HPS and HMX, high zinc/phosphorus oils, in my old cars and am a true believer. Volvo tells me not to use oil additives. Does the high zinc/phosphorus count as an additive?

 

the additive you are referring to is "ZDDP" which has the property of coating metal surfaces when the oil breaks down under heat. Its an old school additive found in "racing oils" but I really doubt it would benefit a modern engine any more than a high quality brand synthetic. My two cents is put this one in the "save your money" category.