A trailer for towing by a power vehicle is provided and generally includes a frame and a tandem wheel assembly. The trailer is provided with a drive assembly having a locking mechanism to selectively engage the drive from the motor to the wheels of the trailer. The locking mechanism having a reciprocating pushing member that may push an urging member to act upon a flanged driveshaft to selectively engage a clutch of the drive assembly.

A gear arm assembly for a vehicle includes gear arm housing having a first end, a second end, and an intermediate portion, the gear arm housing from the intermediate portion to the first end defining a first arm segment, and the gear arm housing from the intermediate portion to the second end defining a second arm segment. The assembly further includes a plurality of gears meshed together in series and housed within the gear arm housing, the plurality of gears including an intermediate gear within the intermediate portion of the gear arm housing. The assembly further includes a first wheel hub connected to a first gear of the plurality of gears at the first end of the gear arm housing, and a second wheel hub connected to a second gear of the plurality of gears at the second end of the gear arm housing. The assembly further includes a primary drive shaft extending into the gear arm housing at the intermediate portion and configured to connect a drive input to the intermediate gear, a spindle housing configured to connect the gear arm assembly to the frame, and a spindle rotatably coupled to and within the spindle housing and configured to allow for rotation of the gear arm housing relative to the spindle housing.

A trailer for towing by a power vehicle is provided and generally includes a frame, a tandem wheel assembly and an extension assembly. The frame forms an undercarriage chassis and the tandem wheel assembly is positioned under the undercarriage chassis. The tandem wheel assembly includes a front wheel assembly and a rear wheel assembly having a drive assembly. The extension assembly moves the front wheel assembly between trailing position and a self-propelled position.

A gear arm assembly for a vehicle includes gear arm housing having a first end, a second end, and an intermediate portion, the gear arm housing from the intermediate portion to the first end defining a first arm segment, and the gear arm housing from the intermediate portion to the second end defining a second arm segment. The assembly further includes a plurality of gears meshed together in series and housed within the gear arm housing, the plurality of gears including an intermediate gear within the intermediate portion of the gear arm housing. The assembly further includes a first wheel hub connected to a first gear of the plurality of gears at the first end of the gear arm housing, and a second wheel hub connected to a second gear of the plurality of gears at the second end of the gear arm housing. The assembly further includes a primary drive shaft extending into the gear arm housing at the intermediate portion and configured to connect a drive input to the intermediate gear, a spindle housing configured to connect the gear arm assembly to the frame, and a spindle rotatably coupled to and within the spindle housing and configured to allow for rotation of the gear arm housing relative to the spindle housing.

A pneumatic drive system for a motorized vehicle includes an air compressor that is operable to couple with a main drive shaft of the motorized vehicle so as to activate the air compressor and generate pressurized air during a braking operation of the motorized vehicle, an accumulator that is operable to receive and store pressurized air from the air compressor during the braking operation, and a pneumatic motor that receives the pressurized air from the accumulator to activate the pneumatic motor. During activation, the pneumatic motor provides energy to the main drive shaft during an acceleration operation of the motorized vehicle.