Mine have generally met with death by misadventure before they ever stop laying. Mine free-range as well, and I've had a few that got hit by cars. Sometimes one will get injured somehow, and I don't know what the heck happened, but a badly injured hen gets the mercy stroke, and then off to freezer camp. One recently got killed by a hawk, the one and only loss to a hawk I've had in over 11 years at this location.
I don't have a lot of predation, but I lose one now and then. I've only have one hen that I know for sure had stopped laying, and she died about 5 months later. The year before that, I was still getting at least 4 eggs a week, I hatched some of them, too. I have at least 2 "daughters of Thelma" running around, I know them for sure because they look like her, she was my only buff orp. Her male offspring went to freezer camp. That other old hen, the one that died on the nest, was a unidentified red hen, I think she may have been a New Hampshire, but I'm not sure. The lady who gave her to me didn't know what she was, she'd ordered from a hatchery, but couldn't remember what she'd ordered. I wouldn't mind having some more of those, she was a great hen. Lots of personality, very funny to watch. And a phenomenal layer, too.