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Vehicle Configuration and Cargo Body

Truck Tractors and Semi-trailers:
A Truck Tractor is a vehicle configuration consisting of a power-unit designed to draw/pull a semi-trailer. Thus, the truck tractor itself has no cargo carrying capability without an attached semi-trailer. A semi-trailer is constructed so that some part of the weight rests upon the power unit. A truck tractor towing another motor vehicle is considered a "truck tractor" vehicle configuration. These vehicle configurations are recorded in SAFETYNET based upon the presence and number of attached semi-trailers as follows.

  1. Truck Tractor (Bobtail)
  2. Tractor Semi-trailer (1 trailer)
  3. Tractor/Doubles (2 trailers)
  4. Tractor/Triples (3 trailers)
Truck Tractor Truck Tractor Towing Other Vehicles
"Bobtail" - No Semi-trailer
A Truck Tractor towing "Saddlemount"
Tractor Semi-trailer Tractor Double Trailers
Tractor Semi-trailer
Tractor/Doubles (2 trailers)