My 4600 has 3200 hours. Starts in summer and winter on the first compression stroke without ever having to use glow plugs. In fact, I've never used the glow plugs and am not sure how to kick them on. My 332s each have around 800 hours and start on the first crank with the glow plugs.
My understanding is that the life of a tractor depends more on the user than the tractor. Well maintained, they seem to last forever. What I see happening is that a tractor accumulates a few years on it, gets dirty, and the owner starts to neglect minor repairs because they're too busy to be bothered with it. The machine starts to look weary, and the owner feels like it's "not worth" fixing. It gets worse and then ends up parked when something breaks. My 4600 and both 332s were all pretty sad looking when I got them, but the diesel engines run like new. One of my 332's was sitting idle in the woods for two years when I bought it, but with some injector cleaner and fresh fuel, it runs like new. Clean it up, fix the broken stuff, treat any rust, put on some fresh paint and a new seat. You've got a tractor that looks and runs like new and will probably outlive you if you keep up with the various repairs along the way.
