We developed a new locomotion mechanism, called TrackWalker in 2010. It consisted of three track modules. It mounts six actuators: three motors for standard tracked locomotion, two motors for sub-tracks' motion to change mounting angles, and one motor for simple legged motion. We conducted outdoor experiments in Mt.Asama in 2010, and we found some problems. Therefore, in 2011, we developed improved version of TrackWalker, called TrackWalker-II, that had low center of gravity, and longer tracks. To validate the mechanism, we conducted outdoor experiments in Mt. Asama again in Oct. 2011. In the field experiment, the robot traversed about 700m on a weak and steep slope (angle: 15-30deg, difference of elevation:160m). (Oct. 2011)