Hi there, I have a 2012 855D XUV (2445hrs) with manual steering. The steering rack appears to have let go. I turn the wheel either way and the there is a clunking and little front wheel movement. Is it common for the racks to fail? It says in the TM that they cannot be serviced, is this for real? Is there a better replacement than a JD original? I see on eBay there are some listed but out of stock. Thanks for any advice.