[Bobcat]

TButtrick .... I don`t have a dog in this at all as I have an ERA , but I also have 30+ years in Hydraulics and over 15 years with hydraulic cylinders . A shock and a hydraulic cylinder have a lot of similarities ... piston , rod , rod end , tube , spherical rod ends etc . They also function somewhat similar . The two biggest failures I saw in the field , specifically sawmills , on kickers and set works carriages were rod end breakage and rod seal leaks . The typical reasons for rod end failures were : misalignment , undersize rod , too small rod thread and not seating the spherical rod end solidly against the shoulder of the rod . This gives you a bending moment and you will get a failure due to metal fatigue ... which is what I think I see on your pictures . Having said this , another type of failure can occur if there is a stress riser where the thread starts on the rod ... caused by the tool being too sharp and not leave enough radius at the starting point . That`s why we rolled our rod threads and didn`t cut them .
A major problem at the mills was the collapsed distance of the cylinder was shorter than the space it had to go in , so the rod end was unscrewed to compensate and a jam nut run up against the rod end . This gave a bending moment on the thread and eventually failure . A solution was to stack a spacer under the rod end and jam nut so the forces were transferred to the unthreaded part of the rod and not the threads .
Please understand that I`m not saying this is what the problem is .... I`m just putting my past experience out there as food for thought . I`m also not saying that the shock supplier has a problem ... again , just my 15 years experience in the field .... and sawmills can be hell on equipment !
Sorry for the long post .