Ok, I’ve updated my rear axle file on Google Drive. The connection to the front has to be readjusted since I had to recenter my axle properly between the tires:

And the front rims and hubs at the rear axle have to be hidden:

So that it looks like this:

Some fineadjustment of the rims to the tires is still necessary as well as some smoothing in the areas of stretching:
