I've sent a couple samples into Blackstone and they've come back pretty good. Usually come back with .4% insolubles and descent wear metals which isn't too bad. They say insolubles are good but then make another note that some soot was found. The oil is not only black, but seems very dirty as well. You get some on your fingers and it stains your skin real bad. Probably gives cancer too. Most of our tractors have black oil but you can just wipe it right off. The OEM filter is an Agco and I don't know where to find any info about those but I look at the Wix and Fleetguard filters and they're only rated at 50 micron. I think with a remote mount filter, like a Fleetguard LF9009, or an LF9691A or any number of others could do a lot better. I should also note we have had some issues with this engine already. At 1000 hours, a connecting rod let loose and blew a hole in the block. Warranty took care of it but they mentioned there was already some sludge building up. So then I cut the service intervals in half, from 400 hours ( as the service manual suggests ), to 200 hours. Just about right at 2000 hours, right after I did an oil change, the engine developed a real bad lifter knock. The dealership came and picked it up and said the valve lash was way out of adjustment and there wasn't hardly any oil getting pumped up to the valve train. The techs at the dealership thought we were running the turbo too hot so the oil was too hot/thin to make it up to the valves. I kinda tend to think, even with the bypass filter, the oil had too much soot in it to make it where it needed to go. We've had other tractors that I've upgraded the primary filter and had noticable results with how much cleaner the oil seems just from pulling the dipstick.