I have been using syn oil for over 20 years in all of my drivers, but not my tractors yet. That's due to the large supply of mineral oil I have yet to use up.
I prefer a syn oil because of it's increased lubricating qualities and have had good results in using it.
My collector tractors get minimum use, so I doubt that I would realize any benefit from using syn oil in them, but I would use it once my supply of mineral oil is exhausted if the price has not gone out of site.
Dan
