Title 23—Highways--Volume 1
PART 658—TRUCK SIZE AND WEIGHT, ROUTE DESIGNATIONS—LENGTH, WIDTH AND WEIGHT LIMITATIONS
§ 658.1   Purpose.
The purpose of this part is to identify a National Network of highways available to vehicles authorized by provisions of the Surface Transportation Assistance Act of 1982 (STAA) as amended, and to prescribe national policies that govern truck and bus size and weight.
§ 658.3   Policy statement.
The Federal Highway Administration's (FHWA) policy is to provide a safe and efficient National Network of highways that can safely and efficiently accommodate the large vehicles authorized by the STAA. This network includes the Interstate System plus other qualifying Federal-aid Primary System Highways.
§ 658.5   Definitions.
Automobile transporters. Any vehicle combination designed and used specifically for the transport of assembled highway vehicles, including truck camper units.
Beverage semitrailer. A van-type, drop-frame semitrailer designed and used specifically for the transport and delivery of bottled or canned beverages ( i.e. , liquids for drinking, including water) which has side-only access for loading and unloading this commodity. Semitrailer has the same meaning as in 49 CFR 390.5.
Boat transporters. Any vehicle combination designed and used specifically to transport assembled boats and boat hulls. Boats may be partially disassembled to facilitate transporting.
Bridge gross weight formula. The standard specifying the relationship between axle (or groups of axles) spacing and the gross weight that (those) axle(s) may carry expressed by the formula:
Cargo-carrying unit. As used in this part, cargo-carrying unit means any portion of a commercial motor vehicle (CMV) combination (other than a truck tractor) used for the carrying of cargo, including a trailer, semitrailer, or the cargo-carrying section of a single-unit truck. The length of the cargo carrying units of a CMV with two or more such units is measured from the front of the first unit to the rear of the last [including the hitch(es) between the units].
Commercial motor vehicle. For purposes of this regulation, a motor vehicle designed or regularly used to carry freight, merchandise, or more than ten passengers, whether loaded or empty, including buses, but not including vehicles used for vanpools, or recreational vehicles operating under their own power.
Drive-away saddlemount vehicle transporter combination. The term drive-away saddlemount vehicle transporter combination means a vehicle combination designed and specifically used to tow up to 3 trucks or truck tractors, each connected by a saddle to the frame or fifth wheel of the forward vehicle of the truck tractor in front of it. Such combinations may include up to one fullmount.
Dromedary unit. A box, deck, or plate mounted behind the cab and forward of the fifth wheel on the frame of the power unit of a truck tractor-semitrailer combination.
Federal-aid Primary System. The Federal-aid Highway System of rural arterials and their extensions into or through urban areas in existence on June 1, 1991, as described in 23 U.S.C. 103(b) in effect at that time.
Fullmount. A fullmount is a smaller vehicle mounted completely on the frame of either the first or last vehicle in a saddlemount combination.
Interstate System. The National System of Interstate and Defense Highways described in sections 103(e) and 139(a) of Title 23, U.S.C. For the purpose of this regulation this system includes toll roads designated as Interstate.
Length exclusive devices. Devices excluded from the measurement of vehicle length. Such devices shall not be designed or used to carry cargo.
Longer combination vehicle (LCV). As used in this part, longer combination vehicle means any combination of a truck tractor and two or more trailers or semitrailers which operates on the Interstate System at a gross vehicle weight greater than 80,000 pounds.
Maxi-cube vehicle. A maxi-cube vehicle is a combination vehicle consisting of a power unit and a trailing unit, both of which are designed to carry cargo. The power unit is a nonarticulated truck with one or more drive axles that carries either a detachable or a permanently attached cargo box. The trailing unit is a trailer or semitrailer with a cargo box so designed that the power unit may be loaded and unloaded through the trailing unit. Neither cargo box shall exceed 34 feet in length, excluding drawbar or hitching device; the distance from the front of the first to the rear of the second cargo box shall not exceed 60 feet, including the space between the cargo boxes; and the overall length of the combination vehicle shall not exceed 65 feet, including the space between the cargo boxes.
Motor carrier of passengers. As used in this part, a motor carrier of passengers is a common, contract, or private carrier using a bus to provide commercial transportation of passengers. Bus has the same meaning as in 49 CFR 390.5.
National Network (NN). The composite of the individual network of highways from each State on which vehicles authorized by the provisions of the STAA are allowed to operate. The network in each State includes the Interstate System, exclusive of those portions excepted under § 658.11(f) or deleted under § 658.11(d), and those portions of the Federal-aid Primary System in existence on June 1, 1991, set out by the FHWA in appendix A to this part.
Nondivisible load or vehicle.
(1) As used in this part, nondivisible means any load or vehicle exceeding applicable length or weight limits which, if separated into smaller loads or vehicles, would:
(i) Compromise the intended use of the vehicle, i.e. , make it unable to perform the function for which it was intended;
(ii) Destroy the value of the load or vehicle, i.e. , make it unusable for its intended purpose; or
(iii) Require more than 8 workhours to dismantle using appropriate equipment. The applicant for a nondivisible load permit has the burden of proof as to the number of workhours required to dismantle the load.
(2) A State may treat as nondivisible loads or vehicles: emergency response vehicles, including those loaded with salt, sand, chemicals or a combination thereof, with or without a plow or blade attached in front, and being used for the purpose of spreading the material on highways that are or may become slick or icy; casks designed for the transport of spent nuclear materials; and military vehicles transporting marked military equipment or materiel.
Over-the-road bus. The term over-the-road bus means a bus characterized by an elevated passenger deck located over a baggage compartment, and typically operating on the Interstate System or roads previously designated as making up the Federal-aid Primary System.
Saddlemount combination. A saddlemount combination is a combination of vehicles in which a truck or truck tractor tows one or more trucks or truck tractors, each connected by a saddle to the frame or fifth wheel of the vehicle in front of it. The saddle is a mechanism that connects the front axle of the towed vehicle to the frame or fifth wheel of the vehicle in front and functions like a fifth wheel kingpin connection. When two vehicles are towed in this manner the combination is called a double saddlemount combination. When three vehicles are towed in this manner, the combination is called a triple saddlemount combination.
Single axle weight. The total weight transmitted to the road by all wheels whose centers may be included between two parallel transverse vertical planes 40 inches apart, extending across the full width of the vehicle. The Federal single axle weight limit on the Interstate System is 20,000 pounds.
Special mobile equipment. Every self-propelled vehicle not designed or used primarily for the transportation of persons or property and incidentally operated or moved over the highways, including military equipment, farm equipment, implements of husbandry, road construction or maintenance machinery, and emergency apparatus which includes fire and police emergency equipment. This list is partial and not exclusive of such other vehicles as may fall within the general terms of this definition.
Stinger-steered combination. A truck tractor semitrailer wherein the fifth wheel is located on a drop frame located behind and below the rear-most axle of the power unit.
Tandem axle weight. The total weight transmitted to the road by two or more consecutive axles whose centers may be included between parallel transverse vertical planes spaced more than 40 inches and not more than 96 inches apart, extending across the full width of the vehicle. The Federal tandem axle weight limit on the Interstate System is 34,000 pounds.
Terminal. The term terminal as used in this regulation means, at a minimum, any location where:
Freight either originates, terminates, or is handled in the transportation process; or
Commercial motor carriers maintain operating facilities.
Tractor or Truck tractor. 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, and a truck tractor equipped with a dromedary unit operating in combination with a semitrailer transporting Class 1 explosives and/or any munitions related security material as specified by the U.S. Department of Defense in compliance with 49 CFR 177.835 may use the dromedary unit to carry a portion of the cargo.
Truck-tractor semitrailer-semitrailer. In a truck-tractor semitrailer-semitrailer combination vehicle, the two trailing units are connected with a “B-train” assembly. The B-train assembly is a rigid frame extension attached to the rear frame of a first semitrailer which allows for a fifth wheel connection point for the second semitrailer. This combination has one less articulation point than the conventional “A dolly” connected truck-tractor semitrailer-trailer combination.
Truck-trailer boat transporter. A boat transporter combination consisting of a straight truck towing a trailer using typically a ball and socket connection. The trailer axle(s) is located substantially at the trailer center of gravity (rather than the rear of the trailer) but so as to maintain a downward force on the trailer tongue.
Width exclusive devices. Devices excluded from the measurement of vehicle width. Such devices shall not be designed or used to carry cargo.
§ 658.7   Applicability.
Except as limited in § 658.17(a) the provisions of this part are applicable to the National Network and reasonable access thereto. However, nothing in this regulation shall be construed to prevent any State from applying any weight and size limits to other highways, except when such limits would deny reasonable access to the National Network.
§ 658.9   National Network criteria.
(a) The National Network listed in the appendix to this part is available for use by commercial motor vehicles of the dimensions and configurations described in §§ 658.13 and 658.15.
(b) For those States with detailed lists of individual routes in the appendix, the routes have been designated on the basis of their general adherence to the following criteria.
(1) The route is a geometrically typical component of the Federal-Aid Primary System, serving to link principal cities and densely developed portions of the States.
(2) The route is a high volume route utilized extensively by large vehicles for interstate commerce.
(3) The route does not have any restrictions precluding use by conventional combination vehicles.
(4) The route has adequate geometrics to support safe operations, considering sight distance, severity and length of grades, pavement width, horizontal curvature, shoulder width, bridge clearances and load limits, traffic volumes and vehicle mix, and intersection geometry.
(5) The route consists of lanes designed to be a width of 12 feet or more or is otherwise consistent with highway safety.
(6) The route does not have any unusual characteristics causing current or anticipated safety problems.
(c) For those States where State law provides that STAA authorized vehicles may use all or most of the Federal-Aid Primary system, the National Network is no more restrictive than such law. The appendix contains a narrative summary of the National Network in those States.
§ 658.11   Additions, deletions, exceptions, and restrictions.
To ensure that the National Network remains substantially intact, FHWA retains the authority to rule upon all requested additions to and deletions from the National Network as well as requests for the imposition of certain restrictions. FHWA approval or disapproval will constitute the final decision of the U.S. Department of Transportation.
(a) Additions. (1) Requests for additions to the National Network, including justification, shall have the endorsement of the Governor or the Governor's authorized representative, and be submitted in writing to the appropriate FHWA Division Office. Proposals for addition of routes to the National Network shall be accompanied by an analysis of suitability based on the criteria in § 658.9.
(2) Proposals for additions that meet the criteria of § 658.9 and have the endorsement of the Governor or the Governor's authorized representative will be published in the Federal Register for public comment as a notice of proposed rulemaking (NPRM), and if found acceptable, as a final rule.
(b) Deletions—Federal-aid primary—other than interstate. Changed conditions or additional information may require the deletion of a designated route or a portion thereof. The deletion of any route or route segment shall require FHWA approval. Requests for deletion of routes from the National Network, including the reason(s) for the deletion, shall be submitted in writing to the appropriate FHWA Division Office. These requests shall be assessed on the basis of the criteria of § 658.9. FHWA proposed deletions will be published in the Federal Register as a Notice of Proposed Rulemaking (NPRM).
(c) Requests for deletion—Federal-aid primary—other than interstate. Requests for deletion should include the following information, where appropriate:
(1) Did the route segment prior to designation carry combination vehicles or 102-inch buses?
(2) Were truck restrictions in effect on the segment on January 6, 1983? If so, what types of restrictions?
(3) What is the safety record of the segment, including current or anticipated safety problems? Specifically, is the route experiencing above normal accident rates and/or accident severities? Does analysis of the accident problem indicate that the addition of larger trucks have aggravated existing accident problems?
(4) What are the geometric, structural or traffic operations features that might preclude safe, efficient operation? Specifically describe lane widths, sight distance, severity and length of grades, horizontal curvature, shoulder width, narrow bridges, bridge clearances and load limits, traffic volumes and vehicle mix, intersection geometrics and vulnerability of roadside hardware.
(5) Is there a reasonable alternate route available?
(6) Are there operational restrictions that might be implemented in lieu of deletion?
(d) Deletions and use restrictions—Federal-aid interstate. (1) The deletion of, or imposition of use restrictions on, any specific segment of the Interstate Highway System on the National Network, except as otherwise provided in this part, must be approved by the FHWA. Such action will be initiated on the FHWA's own initiative or on the request of the Governor or the Governor's authorized representative of the State in which the Interstate segment is located. Requests from the Governor or the Governor's authorized representative shall be submitted along with justification for the deletion or restriction, in writing, to the appropriate FHWA Division Office for transmittal to Washington Headquarters.
(2) The justification accompanying a request shall be based on the following:
(i) Analysis of evidence of safety problems supporting the deletion or restriction as identified in § 658.11(c).
(ii) Analysis of the impact on interstate commerce.
(iii) Analysis and recommendation of any alternative routes that can safely accommodate commercial motor vehicles of the dimensions and configurations described in §§ 658.13 and 658.15 and serve the area in which such segment is located.
(iv) Evidence of consultation with the local governments in which the segment is located as well as the Governor or the Governor's authorized representative of any adjacent State that might be directly affected by such a deletion or restriction.
(3) Actions to ban all commercial vehicles on portions of the Interstate System not excepted under § 658.11(f) are considered deletions subject to the requirements of subsection (d) of this section.
(4) Reasonable restrictions on the use of Interstate routes on the National Network by STAA-authorized vehicles related to specific travel lanes of multi-lane facilities, construction zones, adverse weather conditions or structural or clearance deficiencies are not subject to the requirements of paragraph (d) of this section.
(5) Proposed deletions or restrictions will be published in the Federal Register as an NPRM, except in the case of an emergency deletion as prescribed in § 658.11(e). The FHWA will consider the factors set out in paragraph (d)(2) of this section and the comments of interested parties. Any approval of deletion or restriction will be published as a final rule. A deletion of or restriction on a segment for reasons ascribable to dimensions of commercial motor vehicles described in either § 658.13 or § 658.15 shall result in a deletion or restriction for the purposes of both §§ 658.13 and 658.15.
(e) Emergency deletions. FHWA has the authority to delete any route from the National Network, on an emergency basis, for safety considerations. Emergency deletions are not considered final, and will be published in the Federal Register for notice and comment.
(f) Exceptions. Those portions of the Interstate System which were open to traffic and on which all commercial motor vehicles were banned on January 6, 1983, are not included in the National Network.
(g) Restrictions—Federal-aid primary—other than interstate. (1) Reasonable restrictions on the use of non-Interstate Federal-aid Primary routes on the National Network by STAA-authorized vehicles may be imposed during certain peak hours of travel or on specific travel lanes of multi-lane facilities. Restrictions related to construction zones, seasonal operation, adverse weather conditions or structural or clearance deficiencies may be imposed.
(2) All restrictions on the use of the National Network based on hours of use by vehicles authorized by the STAA require prior FHWA approval. Requests for such restrictions on the National Network shall be submitted in writing to the appropriate FHWA Division Office. Approval of requests for restrictions will be contingent on the ability to justify significant negative impact on safety, the environment and/or operational efficiency.
§ 658.13   Length.
(a) The length provisions of the STAA apply only to the following types of vehicle combinations:
(1) Truck tractor-semitrailer
(2) Truck tractor-semitrailer-trailer.
(b) The length provisions referred to in paragraph (a) of this section include the following:
(1) No State shall impose a length limitation of less than 48 feet on a semitrailer operating in a truck tractor-semitrailer combination.
(2) No State shall impose a length limitation of less than 28 feet on any semitrailer or trailer operating in a truck tractor-semitrailer-trailer combination.
(3) No State shall impose an overall length limitation on commercial vehicles operating in truck tractor-semitrailer or truck tractor-semitrailer-trailer combinations.
(4) No State shall prohibit commercial motor vehicles operating in truck tractor-semitrailer-trailer combinations.
(5) No State shall prohibit the operation of semitrailers or trailers which are 28 1/2 feet long when operating in a truck tractor-semitrailer-trailer combination if such a trailer or semitrailer was in actual and lawful operation on December 1, 1982, and such combination had an overall length not exceeding 65 feet.
(c) State maximum length limits for semitrailers operating in a truck tractor-semitrailer combination and semitrailers and trailers operating in a truck tractor-semitrailer-trailer combination are subject to the following:
(1) No State shall prohibit the use of trailers or semitrailers of such dimensions as those that were in actual and lawful use in such State on December 1, 1982, as set out in appendix B of this part.
(2) If on December 1, 1982, State length limitations on a semitrailer were described in terms of the distance from the kingpin to rearmost axle, or end of semitrailer, the operation of any semitrailer that complies with that limitation must be allowed.
(d) No State shall impose a limit of less than 45 feet on the length of any bus on the NN.
(e) Specialized equipment —(1) Automobile transporters. (i) Automobile transporters are considered to be specialized equipment. As provided in § 658.5, automobile transporters may carry vehicles on the power unit behind the cab and on an over-cab rack. No State shall impose an overall length limitation of less than 65 feet on traditional automobile transporters (5th wheel located on tractor frame over rear axle(s)), including “low boys,” or less than 75 feet on stinger-steered automobile transporters. Paragraph (c) requires the States to allow operation of vehicles with the dimensions that were legal in the State on December 1, 1982.
(ii) All length provisions regarding automobile transporters are exclusive of front and rear cargo overhang. No State shall impose a front overhang limitation of less than 3 feet or a rear overhang limitation of less than 4 feet. Extendable ramps or “flippers” on automobile transporters that are used to achieve the allowable 3-foot front and 4-foot rear cargo overhangs are excluded from the measurement of vehicle length, but must be retracted when not supporting vehicles.
(iii) Drive-away saddlemount vehicle transporter combinations are considered to be specialized equipment. No State shall impose an overall length limit of less or more than 97 feet on such combinations. This provision applies to drive-away saddlemount combinations with up to three saddlemounted vehicles. Such combinations may include one fullmount. Saddlemount combinations must also comply with the applicable motor carrier safety regulations at 49 CFR parts 390-399.
(2) Boat transporters. (i) Boat transporters are considered to be specialized equipment. As provided for automobile transporters in § 658.5, boat transporters may carry boats on the power unit so long as the length and width restrictions of the vehicles and load are not exceeded. No State shall impose an overall length limitation of less than 65 feet on traditional boat transporters (fifth wheel located on tractor frame over rear axle(s), including “low boys,” or less than 75 feet on stinger-steered boat transporters. In addition, no State shall impose an overall length limitation of less than 65 feet on truck-trailer boat transporters. Paragraph (c) of this section requires the States to allow operation of vehicles with the dimensions that were legal in the State on December 1, 1982.
(ii) All length provisions regarding boat transporters are exclusive of front and rear overhang. Further, no State shall impose a front overhang limitation of less than three (3) feet nor a rearmost overhang limitation of less than four (4) feet.
(3) Truck-tractor semitrailer-semitrailer. (i) Truck-tractor semitrailer-semitrailer combination vehicles are considered to be specialized equipment. No State shall impose a length limitation of less than 28 feet on any semitrailer or 28 1/2 feet if the semitrailer was in legal operation on December 1, 1982, operating in a truck-tractor semitrailer-semitrailer combination. No State shall impose an overall length limitation on a truck-tractor semitrailer-semitrailer combination when each semitrailer length is 28 feet, or 28 1/2 feet if grandfathered.
(ii) The B-train assembly is excluded from the measurement of trailer length when used between the first and second trailer of a truck-tractor semitrailer-semitrailer combination vehicle. However, when there is no semitrailer mounted to the B-train assembly, it will be included in the length measurement of the semitrailer, the length limitation in this case being 48 feet, or longer if grandfathered.
(4) Maxi-cube vehicle. No State shall impose a length limit on a maxi-cube vehicle, as defined in § 658.5 of this part, of less than 34 feet on either cargo box, excluding drawbar or hitching device; 60 feet on the distance from the front of the first to the rear of the second cargo box, including the space between the cargo boxes; or 65 feet on the overall length of the combination, including the space between the cargo boxes. The measurement for compliance with the 60- and 65-foot distance shall include the actual distance between cargo boxes, measured along the centerline of the drawbar or hitching device. For maxi-cubes with an adjustable length drawbar or hitching device, the 60- and 65-foot distances shall be measured with a drawbar spacing of not more than 27 inches. The drawbar may be temporarily extended beyond that distance to maneuver or load the vehicle.
(5) Beverage semitrailer. (i) A beverage semitrailer is specialized equipment if it has an upper coupler plate that extends beyond the front of the semitrailer, but not beyond its swing radius, as measured from the center line of the kingpin to a front corner of the semitrailer, which cannot be used for carrying cargo other than the structure of the semitrailer, and with the center line of the kingpin not more than 28 feet from the rear of the semitrailer (exclusive of rear-mounted devices not measured in determining semitrailer length). No State shall impose an overall length limit on such vehicles when operating in a truck tractor-beverage semitrailer or truck tractor-beverage semitrailer-beverage trailer combination on the NN.
(ii) The beverage trailer referred to in paragraph (e)(5)(i) of this section means a beverage semitrailer and converter dolly. Converter dolly has the same meaning as in 49 CFR 393.5.
(iii) Truck tractor-beverage semitrailer combinations shall have the same access to points of loading and unloading as 28-foot semitrailers (28.5-foot where allowed by § 658.13) in 23 CFR 658.19.
(6) Munitions carriers using dromedary equipment. A truck tractor equipped with a dromedary unit operating in combination with a semitrailer is considered to be specialized equipment, providing the combination is transporting Class 1 explosives and/or any munitions related security material as specified by the U.S. Department of Defense in compliance with 49 CFR 177.835. No State shall impose an overall length limitation of less than 75 feet on the combination while in operation.
(f) A truck tractor containing a dromedary box, deck, or plate in legal operation on December 1, 1982, shall be permitted to continue to operate, notwithstanding its cargo carrying capacity, throughout its useful life. Proof of such legal operation on December 1, 1982, shall rest upon the operator of the equipment.
(g) No State shall impose a limitation of less than 46 feet on the distance from the kingpin to the center of the rear axle on trailers or semitrailers used exclusively or primarily to transport vehicles in connection with motorsports competition events.
(h) Truck-tractors, pulling 2 trailers or semitrailers, used to transport custom harvester equipment during harvest months within the State of Nebraska may not exceed 81 feet 6 inches.
§ 658.15   Width.
(a) No State shall impose a width limitation of more or less than 102 inches, or its approximate metric equivalent, 2.6 meters (102.36 inches) on a vehicle operating on the National Network, except for the State of Hawaii, which is allowed to keep the State's 108-inch width maximum by virtue of section 416(a) of the STAA.
(b) The provisions of paragraph (a) of this section do not apply to special mobile equipment as defined in § 658.5.
(c) Notwithstanding the provisions of this section or any other provision of law, a State may grant special use permits to motor vehicles, including manufactured housing, that exceed 102 inches in width.
§ 658.16   Exclusions from length and width determinations.
(a) Vehicle components not excluded by law or regulation shall be included in the measurement of the length and width of commercial motor vehicles.
(b) The following shall be excluded from either the measured length or width of commercial motor vehicles, as applicable:
(1) Rear view mirrors, turn signal lamps, handholds for cab entry/egress, splash and spray suppressant devices, load induced tire bulge;
(2) All non-property-carrying devices, or components thereof—
(i) At the front of a semitrailer or trailer, or
(ii) That do not extend more than 3 inches beyond each side or the rear of the vehicle, or
(iii) That do not extend more than 24 inches beyond the rear of the vehicle and are needed for loading or unloading, or
(vi) Listed in appendix D to this part;
(3) Resilient bumpers that do not extend more than 6 inches beyond the front or rear of the vehicle;
(4) Aerodynamic devices that extend a maximum of 5 feet beyond the rear of the vehicle, provided such devices have neither the strength, rigidity nor mass to damage a vehicle, or injure a passenger in a vehicle, that strikes a trailer so equipped from the rear, and provided also that they do not obscure tail lamps, turn signals, marker lamps, identification lamps, or any other required safety devices, such as hazardous materials placards or conspicuity markings; and
(5) A fixed step up to 3 inches deep at the front of an existing automobile transporter until April 29, 2005. It will be the responsibility of the operator of the unit to prove that the step existed prior to April 29, 2002. Such proof can be in the form of a work order for equipment modification, a receipt for purchase and installation of the piece, or any similar type of documentation. However, after April 29, 2005, the step shall no longer be excluded from a vehicle's length.
(c) Each exclusion allowance is specific and may not be combined with other excluded devices.
(d) Measurements are to be made from a point on one side or end of a commercial motor vehicle to the same point on the opposite side or end of the vehicle.
§ 658.17   Weight.
(a) The provisions of the section are applicable to the National System of Interstate and Defense Highways and reasonable access thereto.
(b) The maximum gross vehicle weight shall be 80,000 pounds except where lower gross vehicle weight is dictated by the bridge formula.
(c) The maximum gross weight upon any one axle, including any one axle of a group of axles, or a vehicle is 20,000 pounds.
(d) The maximum gross weight on tandem axles is 34,000 pounds.
(e) No vehicle or combination of vehicles shall be moved or operated on any Interstate highway when the gross weight on two or more consecutive axles exceeds the limitations prescribed by the following formula, referred to as the Bridge Gross Weight Formula:
(f) Except as provided herein, States may not enforce on the Interstate System vehicle weight limits of less than 20,000 pounds on a single axle, 34,000 pounds on a tandem axle, or the weights derived from the Bridge Formula, up to a maximum of 80,000 pounds, including all enforcement tolerances. States may not limit tire loads to less than 500 pounds per inch of tire or tread width, except that such limits may not be applied to tires on the steering axle. States may not limit steering axle weights to less than 20,000 pounds or the axle rating established by the manufacturer, whichever is lower.
(g) The weights in paragraphs (b), (c), (d), and (e) of this section shall be inclusive of all tolerances, enforcement or otherwise, with the exception of a scale allowance factor when using portable scales (wheel-load weighers). The current accuracy of such scales is generally within 2 or 3 percent of actual weight, but in no case shall an allowance in excess of 5 percent be applied. Penalty or fine schedules which impose no fine up to a specified threshold, i.e. , 1,000 pounds, will be considered as tolerance provisions not authorized by 23 U.S.C. 127.
(h) States may issue special permits without regard to the axle, gross, or Federal Bridge Formula requirements for nondivisible vehicles or loads.
(i) The provisions of paragraphs (b), (c), and (d) of this section shall not apply to single-, or tandem-axle weights, or gross weights legally authorized under State law on July 1, 1956. The group of axles requirement established in this section shall not apply to vehicles legally grandfathered under State groups of axles tables or formulas on January 4, 1975. Grandfathered weight limits are vested on the date specified by Congress and remain available to a State even if it chooses to adopt a lower weight limit for a time.
(j) The provisions of paragraphs (c) through (e) of this section shall not apply to the operation on Interstate Route 68 in Allegany and Garrett Counties, Maryland, of any specialized vehicle equipped with a steering axle and a tridem axle and used for hauling coal, logs, and pulpwood if such vehicle is of a type of vehicle as was operating in such counties on U.S. Routes 40 or 48 for such purposes on August 1, 1991.
(k) Any over-the-road bus, or any vehicle which is regularly and exclusively used as an intrastate public agency transit passenger bus, is excluded from the axle weight limits in paragraphs (c) through (e) of this section until October 1, 2009. Any State that has enforced, in the period beginning October 6, 1992, and ending November 30, 2005, a single axle weight limitation of 20,000 pounds or greater but less than 24,000 pounds may not enforce a single axle weight limit on these vehicles of less than 24,000 lbs.
(m) The provisions of paragraphs (b) through (e) of this section shall not apply to the operation, on I-99 between Bedford and Bald Eagle, Pennsylvania, of any vehicle that could legally operate on this highway section before December 29, 1995.
(n) Any vehicle subject to this subpart that utilizes an auxiliary power or idle reduction technology unit in order to promote reduction of fuel use and emissions because of engine idling, may be allowed up to an additional 400 lbs. total in gross, axle, tandem, or bridge formula weight limits.
(1) To be eligible for this exception, the operator of the vehicle must be able to prove:
(i) By written certification, the weight of the APU; and
(ii) By demonstration or certification, that the idle reduction technology is fully functional at all times.
(2) Certification of the weight of the APU must be available to law enforcement officers if the vehicle is found in violation of applicable weight laws. The additional weight allowed cannot exceed 400 lbs. or the weight certified, whichever is less.
§ 658.19   Reasonable access.
(a) No State may enact or enforce any law denying reasonable access to vehicles with dimensions authorized by the STAA between the NN and terminals and facilities for food, fuel, repairs, and rest. In addition, no State may enact or enforce any law denying reasonable access between the NN and points of loading and unloading to household goods carriers, motor carriers of passengers, and any truck tractor-semitrailer combination in which the semitrailer has a length not to exceed 28 feet (28.5 feet where allowed pursuant to § 658.13(b)(5) of this part) and which generally operates as part of a vehicle combination described in §§ 658.13(b)(5) and 658.15(a) of this part.
(b) All States shall make available to commercial motor vehicle operators information regarding their reasonable access provisions to and from the National Network.
(c) Nothing in this section shall be construed as preventing any State or local government from imposing any reasonable restriction, based on safety considerations, on access to points of loading and unloading by any truck tractor-semitrailer combination in which the semitrailer has a length not to exceed 28 1/2 feet and which generally operates as part of a vehicle combination described in §§ 658.13(b)(5) and 658.15(a).
(d) No State may enact or enforce any law denying access within 1 road-mile from the National Network using the most reasonable and practicable route available except for specific safety reasons on individual routes.
(e) Approval of access for specific vehicles on any individual route applies to all vehicles of the same type regardless of ownership. Distinctions between vehicle types shall be based only on significant, substantial differences in their operating characteristics.
(f) Blanket restrictions on 102-inch wide vehicles may not be imposed.
(g) Vehicle dimension limits shall not be more restrictive than Federal requirements.
(h) States shall ensure compliance with the requirements of this section for roads under the jurisdiction of local units of government.
(i)(1) Except in those States in which State law authorizes the operation of STAA-dimensioned vehicles on all public roads and highways, all States shall have an access review process that provides for the review of requests for access from the National Network.
(2) State access review processes shall provide for:
(i) One or more of the following:
(A) An analysis of the proposed access routes using observations or other data obtained from the operation of test vehicles over the routes;
(B) An analysis of the proposed access routes by application of vehicle templates to plans of the routes;
(C) A general provision for allowing access, without requiring a request, for commercial motor vehicles with semitrailers with a kingpin distance of 41 feet or less (measured from the kingpin to the center of the rear axle, if single, or the center of a group of rear axles). State safety analyses may be conducted on individual routes if warranted; and
(ii) All of the following:
(A) The denial of access to terminals and services only on the basis of safety and engineering analysis of the access route.
(B) The automatic approval of an access request if not acted upon within 90 days of receipt by the State. This provision shall become effective no later than 12 months following the effective date of this rule unless an extension is requested by the State and approved by FHWA.
(C) The denial of access for any 102-inch wide vehicles only on the basis of the characteristics of specific routes, in particular significant deficiencies in lane width.
(j)(1) Each State shall submit its access provisions to FHWA for approval within 6 months after June 1, 1990. In those States in which State law authorizes the operation of STAA-dimensioned vehicles on all public roads and highways, no submission or approval under this paragraph is required. If, in the future, such a State changes its authorizing legislation and restricts the operation of STAA-dimensioned vehicles, then compliance with these provisions will be necessary.
(2) The FHWA will review the access provisions as submitted by each State subject to the provisions in paragraph (j)(1) and approve those that are in compliance with the requirements of this section. The FHWA may, at a State's request, approve State provisions that differ from the requirements of this section if FHWA determines that they provide reasonable access for STAA-dimensioned vehicles and do not impose an unreasonable burden on motor freight carriers, shippers and receivers and service facility operators.
(3) Any State that does not have FHWA approved access provisions in effect within 1 year after June 1, 1990 shall follow the requirements and the criteria set forth in this section and section 658.5 and 658.19 for determining access for STAA-dimensioned vehicles to terminals and services. The FHWA may approve a State's request for a time extension if it is received by FHWA at least 1 month before the end of the 1 year period.
§ 658.21   Identification of National Network.
(a) To identify the National Network, a State may sign the routes or provide maps of lists of highways describing the National Network.
(b) Exceptional local conditions on the National Network shall be signed. All signs shall conform to the Manual on Uniform Traffic Control Devices. Exceptional conditions shall include but not be limited to:
(1) Operational restrictions designed to maximize the efficiency of the total traffic flow, such as time of day prohibitions, or lane use controls.
(2) Geometric and structural restrictions, such as vertical clearances, posted weight limits on bridges, or restrictions caused by construction operations.
(3) Detours from urban Interstate routes to bypass of circumferential routes for commercial motor vehicles not destined for the urban area to be bypassed.
§ 658.23   LCV freeze; cargo-carrying unit freeze.
(a)(1) Except as otherwise provided in this section and except for tow trucks with vehicles in tow, a State may allow the operation of LCV's on the Interstate System only as listed in appendix C to this part.
(2) Except as otherwise provided in this section, a State may not allow the operation on the NN of any CMV combination with two or more cargo-carrying units (not including the truck tractor) whose cargo-carrying units exceed:
(i) The maximum combination trailer, semitrailer, or other type of length limitation authorized by State law or regulation of that State on or before June 1, 1991; or
(ii) The length of the cargo-carrying units of those CMV combinations, by specific configuration, in actual, lawful operation on a regular or periodic basis (including continuing seasonal operation) in that State on or before June 1, 1991, as listed in appendix C to this part.
(b) Notwithstanding paragraph (a)(2) of this section, the following CMV combinations with two or more cargo-carrying units may operate on the NN.
(1) Truck tractor-semitrailer-trailer and truck tractor-semitrailer-semitrailer combinations with a maximum length of the individual cargo units of 28.5 feet or less.
(2) Vehicles described in § 658.13(e) and (g).
(3) Truck-trailer and truck-semitrailer combinations with an overall length of 65 feet or less.
(4) Maxi-cubes.
(5) Tow trucks with vehicles in tow.
(c) For specific safety purposes and road construction, a State may make minor adjustments of a temporary and emergency nature to route designation and vehicle operating restrictions applicable to combinations subject to 23 U.S.C. 127(d) and 49 U.S.C. 31112 and in effect on June 1, 1991 (July 6, 1991, for Alaska). Minor adjustments which last 30 days or less may be made without notifying the FHWA. Minor adjustments which exceed 30 days require approval of the FHWA. When such adjustments are needed, a State must submit to the FHWA, by the end of the 30th day, a written description of the emergency, the date on which it began, and the date on which it is expected to conclude. If the adjustment involves alternate route designations, the State shall describe the new route on which vehicles otherwise subject to the freeze imposed by 23 U.S.C. 127(d) and 49 U.S.C. 31112 are allowed to operate. To the extent possible, the geometric and pavement design characteristics of the alternate route should be equivalent to those of the highway section which is temporarily unavailable. If the adjustment involves vehicle operating restrictions, the State shall list the restrictions that have been removed or modified. If the adjustment is approved, the FHWA will publish the notice of adjustment, with an expiration date, in the Federal Register. Requests for extension of time beyond the originally established conclusion date shall be subject to the same approval and publications process as the original request. If upon consultation with the FHWA a decision is reached that minor adjustments made by a State are not legitimately attributable to road or bridge construction or safety, the FHWA will inform the State, and the original conditions of the freeze must be reimposed immediately. Failure to do so may subject the State to a penalty pursuant to 23 U.S.C. 141.
(d) A State may issue a permit authorizing a CMV to transport an overlength nondivisible load on two or more cargo-carrying units on the NN without regard to the restrictions in § 658.23(a)(2).
(e) States further restricting or prohibiting the operation of vehicles subject to 23 U.S.C. 127(d) and 49 U.S.C. 31112 after June 1, 1991, shall notify the FHWA within 30 days after the restriction is effective. The FHWA will publish the restriction in the Federal Register as an amendment to appendix C to this part. Failure to provide such notification may subject the State to a penalty pursuant to 23 U.S.C. 141.
(f) The Federal Highway Administrator, on his or her own motion or upon a request by any person (including a State), shall review the information set forth in appendix C to this part. If the Administrator determines there is cause to believe that a mistake was made in the accuracy of the information contained in appendix C to this part, the Administrator shall commence a proceeding to determine whether the information published should be corrected. If the Administrator determines that there is a mistake in the accuracy of the information contained in appendix C to this part, the Administrator shall publish in the Federal Register the appropriate corrections to reflect that determination.