Abstract: A hub of an output gear is connected detachably to a rear end of a main power train for an automatic transmission of a front engine rear wheel drive vehicle by means of splines, so that the main power train can be used as a power train of an automatic transmission for a front engine front wheel drive vehicle. The hub of the output gear has an annular groove for receiving a lubricating oil. The annular groove is enlarged in both width and depth so that most of the oil in the annular groove does not rotate together with the output gear and does not hamper the lubricating oil supply through the annular groove.

Abstract: The shift mechanism of an automotive power transmission system is locked in the neutral or parking position by a locking device which is responsive to completion or incompletion of a prescribed manipulative procedure to render a safety device such as a safety belt arrangement into a proper protective position, the locking device including a cam movable with any suitable member of the shift mechanism and a catch member which is moved into locking engagement with the cam if the prescribed manipulative steps to move the safety device into the proper protective position is incomplete.