PURPOSE: To execute tooth hitting sound prevention and restrain the following turning state of wheels caused by the tooth hitting sound prevention in the neutral position of the gear transmission of a vehicle.

CONSTITUTION: Tooth hitting sound preventing means 61, 62 are respectively provided on a gear 13b on a forward stage and a gear 15c on a reverse stage out of gears capable of rotating freely relatively to an output shaft 3 by being supported by the output shaft 3 of a transmission through bearing parts 35 to 39, and frictional force is made to act between the gear 13b and the output shaft 3, and between the gear 15c and the output shaft 3, so as to prevent the tooth hitting sound. As this result, directions of torque applied to the output shaft 3 by frictional force of a tooth hitting sound preventing means 61 for the forward stage and of a tooth hitting sound preventing means 62 for the reverse stage are opposite to each other, thereby two kinds of torque are offset against each other, thereby the following turning state of wheels finally engaged with the output shaft 3 can be restrained.