It seems I'm not the only one who has had some bad luck with the implement lift arm on the supers. I had a run in last winter with an immovable object and my Haban plow. Snapped the arm right off the rock shaft. Seems Cub had a fix for this but as usual I found out after the OOPS! The fix is Cub part# 14297 "cross shaft support strap". You need that and a 1/2" bolt.
Ouch!
The whole assembly in pieces.
The fix.
The strap connects the pin on the right side mower lift arm on the large shaft with the implement lift arm via the drilled hole in the arm. This requires a 1/2" bolt.
Looks like it will add quite a bit of support to the lift arm. The Haban plow and 450 snow blower are a pretty heavy load for this part. Hope this helps keep someone else from having to go replacing the rock shaft. It's not much fun!