The more expensive, heavy-duty versions are motor-driven.

A heavy-duty version of the F-150 designed for more serious towing and hauling while maintaining a high degree of pampering.

New Zealand Government Railways, during the 1970s, developed an extremely large and heavy-duty version of the chopper coupler.

The Ford Sterling 9.75 axle was also optioned in heavy-duty versions.

It was a heavy-duty version of a civilian Sky Rover with four ground wheels instead of landing skids.

The more expensive, heavy-duty versions are motor-driven (usually by an electric motor).

The 500 through 700-series were medium duty only, while 900 and 1000 series were reserved for heavy-duty versions.

Motor Trend and Car and Driver, have earlier reported Toyota will produce a heavy-duty version of the Tundra designed to compete in the 3/4-ton class.

There was also a heavy-duty version designated BR2.

A heavy-duty version of ControlTrac was introduced in 1996 for the 1997 model year on the first generation Ford Expedition full-size sport utility vehicle.