Rear Axle Broken Pinion

[Leo B]

Hi,
This might also be of interest to this forum. I wrote about this on Facebook. When I left the traffic lights (standard way) the rear axle pinion broke as you can see in the pictures. I think the best estimate is that it is a manufacturing defect (hydrogen embrittlement during manufacturing) that has lasted for decades. I don't think the warranty is valid anymore 🙂 

[mfg]

Wow!…. And you didn’t ‘drop the hammer’?

[Leo B]

mgf... Not at all 🙂
As you can see. There is a fragile area in the metal with a wavy pattern. A manufacturing defect in the hardening, which however lasted for decades until it gave way with normal movement. It's a wonder it took this long.

[mfg]

17 minutes ago, Leo B said:

mgf... Not at all 🙂
As you can see. There is a fragile area in the metal with a wavy pattern. A manufacturing defect in the hardening, which however lasted for decades until it gave way with normal movement. It's a wonder it took this long.

Extremely interesting!

[Mark L]

The final fracture occurred suddenly in the small, "frosty" looking area. The crack spread gradually across the larger area where the "tree rings" are located.

[Leo B]

Mark L...
This picture is before cleaning. Here you see dark fragile (frosty) area which has been there very long time.

Edited July 30, 2025 by Leo B