Rear axle broke right inside cover

[smallfarmer]

I am looking for any thoughts advice on why my rear axle would have broke right inside the cover, between the bearings and nut. I was plowing and I hear a crack and then the tractor would not move forward. At first I thought it was a transmission problem but I tried locking the differential and then I could move forward. I got out and saw the right wheel at the axle seal was leaking.

So took off the whole wheel / assembly and yep, it broke just about an inch inside the axle hub. Lucky to not have been under or in the tractor when it fell. As it was, we had it jacked up when we took off the tire and it was just shocking to see how little of the axle shaft was holding it up...

Any thoughts on why that would happen? My tractor is a 1979 M4000. Thanks.

 

[ETRon]

Age and metal fatigue are what comes to mind. Just outside the bearings is the highest stress point (IMHO). After 34 years or so, if it's been worked hard I'm not sure you can hardly fault it. Should be able to find a replacement in a tractor graveyard.

 

[hodge]

X2. Age, fatigue, and how many different people have used the tractor in those years? Not everyone respects machinery and drives it accordingly. Some people could break an anvil with a rubber mallet- who knows how they treated your tractor? I'm not accusing, just generalizing. 34 years is a lot of time and use- the older a piece of equipment gets, the more likely it is that something will break.
you might try West Kentucky Tractor Parts (wkytpstore.com) they have a tractor graveyard.

 

[olthumpa]

X2. Age, fatigue, and how many different people have used the tractor in those years? Not everyone respects machinery and drives it accordingly. Some people could break an anvil with a rubber mallet- who knows how they treated your tractor? I'm not accusing, just generalizing. 34 years is a lot of time and use- the older a piece of equipment gets, the more likely it is that something will break.
you might try West Kentucky Tractor Parts (wkytpstore.com) they have a tractor graveyard.

I have had good luck getting scarce parts from them.

Good luck!

 

[ETRon]

yep.. West Kentucky - just couldn't think of the name when I wrote the last message!