I bought a 10 year old Bad-Boy 60" that had a transaxle concern. The original owner maintained 7 acres with it all that time. Found out that the blades were COMPLETELY worn out, almost to a point on each end, thin and cracked. The fan blades were broken on one tranny, and guess it over heated. I serviced 26 hp Briggs, transaxles, greased, & replaced spindle bearings, and put on a new set of blades. I have 150 hours on it now, and it does a fantastic job. There is no hour meter on it. I am curious as to how many hours it could have on it. I doubt that the blades had ever been changed. If they can go 1000 hours, I would guess it is in that neighborhood. Has anyone seen blades that worn out - and how many hours would it take? It is certainly not safe, and I have never done that. I have 600 hours on my cub cadet 1500 tractor, and the blades are fine. It has never been around gravel etc. That would make a big difference I know.