A vehicle drive unit and land vehicle comprising the drive unit are disclosed. Each drive unit comprises a pair of longitudinally spaced apart rotatable drive structures. The land vehicle comprises a pair of drive units on opposite sides thereof. The drive units comprise an electric motor for powering the rotatable drive structures and a gear drive assembly comprising structure for disengaging the electric motor. The drive units may be remotely controllable, may be water-tight and may be floatable. The vehicle comprising the drive unit may be amphibious.

A retractable land propulsion assembly for an amphibian including a retraction linkage movable between a protracted position and a retracted position, an actuator for moving the retraction linkage between the protracted position and retracted position, and at least one wheel and/or track drive. When the retraction linkage is protracted then the retraction linkage supports and/or holds the at least one wheel and/or track drive in a ground engaging position for use on land. The retraction linkage comprises at least one component or part or portion thereof that passes through an overcentre position on protraction to prevent forces received in use via the at least one wheel and/or track drive from acting to retract the retraction linkage.

The present invention provides, with reference to FIG. 1, an amphibian for use in land and marine modes comprising: a planing hull; three wheel stations, two of the three wheel stations being front wheel stations provided one on each side of and in the front half of the amphibian, and the third wheel station being a rear wheel station provided in a central region in the rear half of the amphibian; at least one wheel provided at each wheel station, each wheel being movable between a protracted land mode position and a retracted marine mode position; land propulsion means to propel the amphibian on land in the land mode, the land propulsion means comprising at least one of the wheels; and marine propulsion means to propel the amphibian on water in the marine mode, the marine propulsion means comprising at least two impellers or propellers provided one on each side of the rear wheel station.

A suspension element includes a housing, a first joint, and a second joint. The housing is configured to couple a tractive element assembly to a vehicle. The housing has a first end configured to engage a portion of the vehicle and a second end configured to interface with the tractive element assembly. The first joint includes a first actuator and a first resilient member. The first actuator is configured to facilitate linear extension and retraction of the suspension element. The second joint includes a second actuator and a second resilient member. The second actuator is configured to facilitate rotational movement of the suspension element. The first resilient member and the second resilient member are configured to support a static load of the vehicle.

A liftable rear suspension system of an amphibious vehicle is provided, including a differential gear installed inside a vehicle body frame, and a brake disc installed on the inner side of a hub of a vehicle wheel, with a brake arranged on an outer edge of the brake disc and a flange plate fixed on the inner side of the brake disc. A universal joint arm is rotatably installed on the periphery of one end, close to the vehicle body frame, of the flange plate through a bearing. The flange plate is connected to an output shaft of the differential gear through a cage universal joint. A worm gear is rotatably installed on the periphery of one end, stretching out of the vehicle body frame, of the output shaft through a bearing. A pair of bearing seats are installed on the vehicle body frame through an installation rack.