I have two JD310SE backhoes, one has about 3000hrs the other has about 4000hrs, both smoke under compression. No smoke under load. Both started to smoke at about 2000hrs. Traveling down hill under compression the tractors smoke but when you get back on the throttle the smoke clears up. Does not affect preformance of engine.Is this a problem with the 310SE's? My dealer says no. Has anyone had this problem and did you repair it? Thanks Ed