A speed change device that includes a first clutch that has a first piston, a first engagement oil chamber, and a first centrifugal hydraulic pressure cancellation chamber configured to cancel a centrifugal hydraulic pressure generated in the first engagement oil chamber; a second clutch that has a second piston, a second engagement oil chamber, and a second centrifugal hydraulic pressure cancellation chamber configured to cancel a centrifugal hydraulic pressure generated in the second engagement oil chamber and that is disposed around the first clutch; and a drum member that defines the first engagement oil chamber together with the first piston and that defines the second engagement oil chamber together with the second piston.

A speed change device that includes a first clutch that includes a first piston, a first engagement oil chamber, and a first clutch drum that has a first outer tubular portion which extends in an axial direction and with which an outer peripheral portion of a first friction engagement plate is fitted, and a second clutch that includes a second piston, a second engagement oil chamber, and a second clutch drum that has a second inner tubular portion that extends in the axial direction and that slidably supports an inner peripheral portion of the second piston.

A clutch control device is provided for a four-wheel drive vehicle. The clutch control device is able to suppress the elevation of the temperature of the oil supplied to a friction clutch during two-wheel drive travel when the friction clutch is released. The clutch control device includes a dog clutch and an electronic control coupling. The friction clutch is housed in a coupling case. When the dog clutch and the friction clutch are released, a two-wheel drive mode is selected. The coupling case has a passage opening that is closed to retain lubrication oil in an oil chamber with respect to a clutch chamber that houses the friction clutch. When oil stirring conditions are met thereafter, the passage opening is opened and the lubrication oil is allowed to flow into the clutch chamber from the oil chamber.

A connection structure of a hose for transmission oil including a multilayer hose having a first rubber layer formed by a first pipe, a braided layer formed on an outer surface of the first rubber layer and formed by braiding aramid fibers. A second rubber layer located on the outer surface of the first rubber layer. A first connector including a body inserted into an inside of the first rubber layer and including a second pipe connected with the first pipe, and a stopper protruding from the body, and an inclined portion formed at an end of the body and forming an uphill slope of 1117 to one side of the body. A second connector including a cover portion covering the multilayer hose and a plurality of pressurized portions formed concave with respect to an outer peripheral surface of the cover portion and in contact with the multilayer hose.

A connection structure of a hose for transmission oil including a multilayer hose having a first rubber layer formed by a first pipe, a braided layer formed on an outer surface of the first rubber layer and formed by braiding aramid fibers. A second rubber layer located on the outer surface of the first rubber layer. A first connector including a body inserted into an inside of the first rubber layer and including a second pipe connected with the first pipe, and a stopper protruding from the body, and an inclined portion formed at an end of the body and forming an uphill slope of approximately 11-17 to one side of the body. A second connector including a cover portion covering the multilayer hose and a plurality of pressurized portions formed concave with respect to an outer peripheral surface of the cover portion and in contact with the multilayer hose.