I got a 4230 John Deere with a quad range about a year ago now and after about 50 hours on it the front hydraulic pump seized because the transmission pump was so wore out. So over the winter I replaced both pumps and everything seemed to be good again but now recently I went to go mow out a pasture with a small 6 foot rough cut but I had the problem that the pto wouldn't stay engaged and it would hardly pick up the mower. Now I went to try and figure out what was wrong and went and tested all the test ports I am getting 40psi at the oil filter bypass valve, 140psi at the clutches and 2300psi at the scv's. I also took the main pump feed hose off and put it in a bucket to see how much oil was coming out and in about 40 seconds it pumped about 3L which seems way too low. The oil is clean and so is the filter and the screen. I also took the transmission pump drive shaft out to see if it was stripped off but it looks fine and the when I spun the pump by hand I could feel it build resistance. Is it possible when I had the rock shaft housing off that something fell in and is causing a blockage? Other than that I'm at a loss and I really don't know where to look elsewhere. I'm open to any advise.