Couldn't tell you if the guide cable broke because the window was frozen in place during an ice storm, and like a true Southerner, I tried to crank it down to clear the snow and ice. At least the window stayed in the upright and closed position.Yes, I know, if I were from Cleveland, I would have known better! Or was it a failure of the cable.... which had rusted... but it broke never the less...Did not waste my time trying to claim against the "Lifetime" warranty, as the original factory unit lasted 11 years. Less than 4 years does not constitute quality to me. The OE unit was AC Delco, so that is what is now in place. The AC Delco is much faster than the Dorman... both look identical. If you need to replace this mechanism, a visit to YouTube will give you numerous pointers to make the task easier.