I have had this tractor a couple years and used it hard(dragging logs and picking up rounds with front bucket,etc) and now when I jack up front axle(4 whl dr.) there is wheel bearing play-not in the knuckle bearings but in wheel bearings. I unbolted the unit and put in new bearings but I don't see any shims-still has significant play in it. Also I haven't added ballast to the rear(other than water in the tires) because most of the time I had the JD backhoe attachment on it). Anybody got ideas?