A transmission includes: a plurality of rotating elements interposed between a driving source and an output portion; a rotating member that rotatably supports one of the rotating elements and is formed at a radially outer portion thereof with a plurality of recesses or protrusions; a support member having a surface, that is facing the rotating member, and a plurality of protrusions or recesses that are formed in a radially inner portion thereof and engage with the recesses or protrusions of the rotating member, the rotating member being mounted in the support member such that the rotating member is not able to rotate; and a friction producing mechanism that is provided between the rotating member and the above-indicated surface of the support member and is arranged to produce a frictional force between the rotating member and the surface of the support member.