Sir,

I have the same tractor....And wonder why you would want to do this...I mean mine is and has been running just fine for all these years. I use a straight 40W non detergent oil, as it has had since my Grandfather bought it. I run mine however enough each year to refresh the oil in the oil box. If you don't run yours that much maybe it might make sence. I doubt if anone else is doing this however.

Regards, Kirk