Seen a Youtube video posted by a contractor showing how his machine had cracked where the loader arms hook to machine up by windshield. Said he know of others with same. Design problem. Anyone heard of this? It is left side only. Had to remove arms and cab to repair. I did search on this site and nobody has ever posted anything about such.
Without seeing the video it's difficult to comment. The first thought that springs to mind is that the 953C has two arrangements, Standard and Waste Handling. The WH Arrgt is beefed up over the Standard one, so cracking as a result of incorrect machine application by using a Std machine where a WH Arrgt was required might be regarded as somewhat expected. It's also pretty easy to point the finger at bad design if you find a 12"-long crack. The response would be "Well if you were doing inspection right you'd have found it when it was 1" long..!!" There is nothing on the books regarding reinforcement or repair of 953C chassis. EDIT: I found the video and watched the relevant part of it. That crack shown there developed over weeks if not months IMO. In the state it ended up it would have been pretty involved to fix it. Apart from that there was so much grease lathered around the area it would've been almost impossible to inspect it properly.
I've seen a lot of welding work go to waste because they didn't grind out the entire crack before welding. That little sharp point is called a stress riser. You start pushing on it and the forces get focused on that old injury and at that old little piece of crack it starts expanding again.
Thanks for having a look at the video. I thought if it were common I would have found more information on this or other sites. So far, I have seen no post.
Welding technique can be absolutely critical for some repairs. Even where you start and stop can be the difference between a good repair and a repair that won't last.