I have owned the tractor for 2 years, mowing commercially. Its mostly spindle problems. I have made a list of most of the common problems I can recall:
The aluminum bearing housings break (probably replaced 5)
The spindle drive pulleys strip out, this happens very easy, but its easily fixable by welding the pulley, nut, and spindle center together (probably have done this 4 times)
The bolt that holds the blades breaks or strips out, out. The blade can be welded to the spindle, but that doesn't work great. (probably happened 7 times)
The belt falls off (probably 40 times), or breaks (3 times)
The plastic wheels break, and they are expensive (at least 8 times)
The deck mounting hardware is just junk, the hangers break in multiple spots, the front mount falls off all the time
When the grass is tall, this deck does not cut well, it leaves allot still standing
The spindle mounting spots of the thin stamped deck bend, this is almost impossible to get perfect again.
For some repairs, I have found ways to make it stronger, and eliminate that part from breaking again. (shouldn't john Deere have tested this piece of junk before mass producing it?)
The lawns I mow are not that rough, There is noting more frustrating than having to leave a job to make repairs. This deck is just a poorly designed piece of junk, similar to what a cheap home owner lawn mower would have. The tractor should have a much stronger fabricated deck, similar to what a commercial zero turn mower. I've just listed the mower for sale after about 8 repairs this week. I don't know what to get, I don't like zero turns because they get stuck in mud, and on steep hills. I really just want a good deck for this tractor.