OIL PASSAGE STRUCTURE FOR AUTOMATIC TRANSMISSION

An oil passage structure includes an oil passage constituted by a first groove formed in a first wall and a second groove formed in a second wall. The first wall has a first recess recessed toward one side in an axial direction. The second wall has a second recess that is located at a position different from the first recess in a radial direction of a main shaft and that is recessed toward another side in the axial direction. A portion of a first component is disposed in the first recess, a portion of a second component is disposed in the second recess, and, in the oil passage, a second passage located at a position corresponding to the second recess is located on the other side in the axial direction relative to a first passage located at a position corresponding to the first recess.