I'm back on the road! This is my old final drive. The part in front is the part that failed. There are splines on the bottom shaft that you can see if you look closely. Near the gear in the center the spline were worn beyond belief. For this part to disengage from the unit it is usually necessary to heat it to 200 degrees C. The tolerances are that tight. Mine just dropped out cold.
This part wobbling also caused damage to the brake rotor and it also had to be replaced.
Parts, labor, and CA taxes... $3100 out the door!