case 850b angle cylinder rod breakage

cant find cause of angle cyliner rods breaking.cant doze 30 min till one side or other breaks.though maybe my welding was problem so had 2 different pro welders try it with same results.could center pin bushing failure cause this?also wonder if length of rods might b cause.as much as theyve been ground on and welded i figure their lengths have changed.clay dirt with some shell rock is what im workin in.so thats not the issue.any suggestions would b greatly appreciated.thanks

case 850b angle cylinder rod breakage