Differential Drive flange output grinded down. Cause?

[Jerezblack.m3]

Can you guys help me identify what caused this?
https://ibb.co/m5rHTSy
https://ibb.co/KbsBCXP



Was just driving on the freeway and all of a sudden the car wanted to steer to the left and i just hear clicking noise. So i pulled over and couldnt find any problems and when i was trying to merge back to the freeway, the car wouldnt get traction and would just steer to the left. So i had it towed to the shop and they showed me the pictures above.

Note: had the differential serviced on november, replaced all the gasket because it was leaking

[doogee]

Looks like the shop didn't completely seat the flange back into the differential when they removed it to replace the seal.

[pbonsalb]

The axle popped out or was not fully seated and then popped out? Those 2 lock rings are supposed to keep it in the diff, but an axle can pop out. I experienced that on my E36 a few years ago. Not sure why it happened in my case — perhaps the suspension was flexed in some strange way that allowed the axle to move outward.

[bmwpower603]

I’m sure there is a specific tool that presses that into the differential. And if that tool is not used, maybe this is what happens?

Hopefully your diff is okay?

[pbonsalb]

There is no tool. Just push it in. You might feel the lock rings snap into place.

For removal, once the axle is disconnected from diff output stub, you can pull the stub out with your hands. It isn’t really locked in there hard. It’s the axle bolted to it and bolted to the trailing arm and the other suspension parts bolted from the subframe to the trailing arm that really hold it in place.

[Theodore]

As already mentioned, this could have been the cause.

[deansbimmer]

Agreed. Output flange was not seated fully when reinstalled.