How do I fix my steering on my 2010 John Deere LA 165?

How do I fix my steering on my 2010 John Deere LA 165? I know how to do the basics and I have done all the maintenance every interval that it requires to be serviced and then some. I have lubed the steering and have noticed that it had some wear on it after 100 hours. It just turned exactly 200.2 hours and the steering had when out completely. This is ridiculous because I had a 1997 LT 166 do the same. I hate to spend all this money for it do this over again. How should it be fixed?