they bend from torque. you may want to check the outdrives on the trany and axle to see if the dog bones have tweaked slots into the outdrives. this will cause the bones to brake and twist easyer. CVDs is the only way to go. I broke about 70+ until i got the cvds and have never looked back. You could also try losening up the diff. (if its locked out) or your slipper to keep them from getting tweaked.