Yeah, all this talk makes me want to add some EOS to my engine. I recently decided to use some OLD (unopened NOS) oil I got from the junkyard, to thin it down for the colder temps as the 15-40 Delo (CI-4 i have been stock piling) is too thick for these colder temps in NE. Every once and awhile I found some old oils at the yards and i have been stock pileing it as I get it. So when the colder temps came I switched the oil and added some Quaker state 10-30 from 1988-1989 time frame and added a some EOS for good measure. I figured since I hardly run it this time of year that it can only help, especially upon initial startup .