Originally Posted By: onion
It was the "gudgeon nut" on a 9400 John Deere 4wd tractor- one of those that has weighs about 50,000 pounds and has about 400hp. The 'gudgeon' (a term that I've never heard elsewhere) is the pin, about 10" in diameter, that allows the front and rear halves of the tractor to swivel (not steer, but swivel- this pin is parallel to the direction of travel). It was rusty and put up a [censored] of a fight.
I know what you mean. Wow. I thought the flywheel bolts om a Cat D399 were serious.