(2) The forward input gear (left) and the reverse input gear (right) are free to rotate on the input shaft assembly when the forward and reverse shuttle clutches are not engaged. When the forward input gear is engaged, it transfers power to the countershaft. When the reverse input gear is engaged, it transfers power to the reverse idler driven gear. The reverse idler driven gear turns the reverse idler shaft and reverse idler input gear, which is splined to the countershaft.