TN Code § 55-7-201 (2021)
2021 Tennessee Code|Title 55 - Motor and Other Vehicles|Chapter 7 - Size, Weight and Load|Part 2 - Weight and Length Specifications|§ 55-7-201. Maximum Length of Vehicles

  For purposes of this section, “truck tractor” means the noncargo carrying power unit that operates in combination with a semitrailer or trailer, except that a truck tractor and semitrailer engaged in the transportation of automobiles may transport motor vehicles on part of the power unit.   No motor vehicle as defined in § 55-1-103 consisting of a straight truck whose length, including any part of its body or load, exceeds forty-five feet (45') and no straight truck with trailer attached, the total length of which combination, including any part of the body or load, exceeds sixty-five feet (65') shall be operated on any highway.   Motor vehicles consisting of a truck-tractor and semitrailer or trailer combination shall be permitted to operate over the federal and state highway system; provided, that the towed vehicle shall not exceed fifty-two feet (52') in length from the point of attachment to the tractor. If the towed vehicle exceeds forty-eight feet (48') in length from the point of attachment to the tractor and the load on the vehicle does not consist of livestock, motor vehicle parts, or motor vehicles, or any combination of such items, the distance between the kingpin and a point midway between the two (2) rear axles shall not exceed forty-one feet (41'). The distance between the kingpin and the rearmost axle, if the axles are not a tandem axle, shall not exceed forty-four feet (44') .   Motor vehicles consisting of a truck-tractor and twin trailer combination shall be permitted to operate on the national network of highways, including interstate highways and the additional highways identified in 23 CFR Part 658, Appendix A; provided, that neither of the towed vehicles shall exceed twenty-eight feet six inches (28' 6") in length.   No twin trailer truck authorized by this chapter shall be operated on any highway designated as a scenic highway under the authority of title 54, chapter 17. The national network of highways, including interstate highways and the additional highways identified in 23 CFR Part 658, Appendix A, shall not be considered scenic routes for purposes of this chapter.   The limitation as to length stated in this section shall not apply to loads of poles, logs or timber in single length pieces; provided, that no motor vehicle, including any part of the body or load, transporting such material shall be in excess of seventy-five feet (75') in length unless a permit has first been obtained as authorized in § 55-7-205.   The length limitations described in this section shall be exclusive of safety and energy conservation devices designated by the commissioner except that no device excluded from the limitations of this section shall have by its design or use the capability to carry cargo.   It is not a violation of the length limits set forth in this section when any otherwise properly titled and registered vehicle, which is in compliance with applicable length requirements, is disabled on the highways and requires a tow or other assistance in proceeding to an exit or a repair or terminal facility within one hundred (100) miles of the point where the vehicle became disabled, and the combined lengths of the disabled vehicle and the tow vehicle exceed the limits in this section. This exemption shall only apply to vehicles disabled while operating on the highway, and only when authorized by the owner, terminal manager, owner's agent, or law enforcement official.    Notwithstanding any other maximum vehicle length provision of this section, a stinger-steered automobile transporter with a front overhang of less than four feet (4') and a rear overhang of less than six feet (6') shall be permitted to operate on the national network of highways, including interstate highways and the additional highways identified in 23 CFR Part 658, Appendix A, up to a maximum vehicle length of eighty feet (80').   For purposes of this subsection (i), a “stinger-steered automobile transporter” means an automobile transporter, which is a vehicle combination designed and used specifically for the transport of assembled automobiles, that has a fifth wheel located on a drop frame behind and below the rear-most axle of the power unit.      Notwithstanding any other maximum vehicle length provision of this section, a towaway trailer transporter combination shall be permitted to operate on the national network of highways, including interstate highways and the additional highways identified in 23 CFR Part 658, Appendix A, up to a maximum vehicle length of eighty-two feet (82').   For purposes of this subsection (j), a “towaway trailer transporter combination” means a combination of vehicles consisting of a trailer transporter towing unit and two (2) trailers or semitrailers in which:  The total weight does not exceed twenty-six thousand pounds (26,000 lbs.); and   The trailers or semitrailers carry no property and constitute inventory of a manufacturer, distributor, or dealer of such trailers or semitrailers.       This section shall be enforced in accordance with all applicable provisions of federal law regarding the operation of vehicles on the national network of highways, including interstate highways and the additional highways identified in 23 CFR Part 658, Appendix A.