Run 7230 with Harvest services feeder chain. 1000sep hrs. Combine just went through dealer inspection and of course the usual; hole in the RH side cone and feeder house gearbox shaft/top sprocket wore out. The top sprocket is a pricey bi*tch at dealer but it does have the build in slip clutch whereas local part supplier can get a non CNH top sprocket with no clutch for 1/3 the price. Question is is it necessary to have the built in slip clutch in the sprocket? There are slip clutches in the gearbox but maybe with the way the earlier flagships ate feederchains the second clutch was necessary? Also on this machine the inspection door that runs across top of feeder house directly above top sprocket is always bent up and out of shape from the crop inside the house. Not sure why as the other identical machine is normal.