We recently purchased a Mit2050FD. Front end loader and rear hydraulics were working. Now the Front end loader works but the rear will not go up or down except when we manuever the bucket the rear hydraulics goes up at the same time. When we try to raise rear hydraulics, when not using front loader, sometimes the rear goes up and down, slowly and sometimes it doesn't. We have a mower on the rear 3pt hitch. We checked the hyd/trans oil by unscrewing the plug on the side. Oil ran out immediately, so we were told that if that happens it is full. What could the problem be.