My Toro Z Master has about 110 hrs on it now. I think it is 4 years old. I check the fluids regularly and do a service at the beginning of the season. Last check of hyrodraulics showed a loss of fluids. It took a half a cup to get it back a level. Brought the tractor up to the garage and was jacking up the rear end when a odd sight occurred. As the rear tire was breaking contact with the driveway, it was tilting inward, like a front suspension of car would do. Odd for sure, no independent suspension on this thing. When I grabbed the tire a shook it, the assembly was loose big time. Turns out both rear tires were way loose, even shed one of the nuts completely off the bolt that holds the housing to the frame. These were not lug nuts, but bolts holding the bases. This is a commercial mower that I would not have suspected of such wear. I have the feeling the assembly was never done correct in the first place.