Synthetic oil with E.O.S.?

T Spool

New Member
Jun 28, 2006
Anybody run zinc additives with synthetic oil?

Are there any negatives to adding E.O.S. or STP to synthetic oil?
I run mobil 1 with a bottle of EOS every oil change. There is no problem with doing this. It just adds more extreme press. additives that flat tappet cams need to survive.

Ive been doing this for years on my car.
Thanks guys. I have also been running Mobil 1 on my 80K stock block with no issues, but I will start supplementing with EOS to be safe.