Roy is asking the question that is also bothering me. If we can ask the Original Poster, at what point (engine hours) did you change out the original fill of factory break-in oil, and what did you put in it then for oil? In that first 100 hours, did you do some real work with the tractor?
My local dealer has told me for the past ten years, everytime the sell a new tractor they recommend trying to do some meaningful work in the breakin period, then change the oil the first time by putting JD breakin oil again for 50 more hours. I always say that the tractor should be pulling a ground engaging operation like disking or something, and work it hard enough to make it smoke a bit and pull the rpm down. And of course I'd run it at PTO speed while doing it. A couple hours of that ought to do it.