Mine lasted 290,000km. Changed the oil and filter every 40,000km since I've had it (102,000).
Beware reversing uphill/ under load when they've got a few km on them, that's what did mine in as I was reversing a loaded 8x5 trailer up a hill a few times a week for 2 months
The sealing rings on the forward clutch wear and allow it to part engage still when reverse is selected, so you're trying to go forwards and backwards at the same time.
The forward clutch burns out because it is only partly engaged. The rest of the clutches looked great when I pulled it down, but the forward clutch was worn and burned.

