2023 Iowa Code › Title VIII - TRANSPORTATION › Chapter 321 - MOTOR VEHICLES AND LAW OF THE ROAD › Section 321.457 - Maximum length.

321.457 Maximum length.
1. A combination of four vehicles is not allowed on the highways of this state, except for power units saddle mounted on other power units which shall be restricted to a maximum overall length of ninety-seven feet.
2. The maximum length of any motor vehicle or combination of vehicles operated on the highways of this state is as follows:
a. A single truck, unladen or with load, shall not have an overall length, inclusive of front and rear bumpers, in excess of forty-five feet. When determining the overall length of a single truck, the following shall be excluded:
(1) Cargo extending not more than three feet beyond the front bumper and not more than four feet beyond the rear bumper when transporting motor vehicles, boats, and chassis.
(2) An unladen cargo carrying device extending no greater than twenty-four inches from the rear of the bed of the truck.
(3) A cargo carrying device with load.
b. A single bus shall not have an overall length, inclusive of front and rear bumpers, in excess of forty-five feet, except that buses constructed so as to contain a flexible part allowing articulation shall not exceed sixty-one feet.
c. A manufactured or mobile home not in excess of forty-eight feet in length may be drawn by any motor vehicle, except a motor truck, provided that the manufactured or mobile home and its towing unit are not in excess of an overall length of sixty feet. For the purposes of this subsection, a light delivery truck, panel delivery truck, or “pickup” is not a “motor truck”. A portable livestock loading chute not in excess of a length of thirteen feet including its hitch or tongue may be drawn by any vehicle or combination of vehicles, provided that the vehicle or combination of vehicles drawing the loading chute is not in excess of the legal length provided for such vehicles or combinations.
d. A combination of three vehicles coupled together one of which is a motor vehicle, unladen or with load, other than a truck tractor, shall not have an overall length, inclusive of front and rear bumpers, in excess of seventy feet.
e. A motor vehicle or combination of vehicles may be operated upon the highways of this state, irrespective of the length and weight limitations imposed by the laws of this state, if the motor vehicle or combination of vehicles is operated within the corporate limits of a city abutting a border of this state and such operations have been approved by ordinance of the city council and if the length and weight of the motor vehicle or combination of vehicles is in conformity with the laws relating to length and weight of the abutting state. If a city council has authorized such operation upon highways within the corporate limits, then the limit of travel for such motor vehicles or combination of vehicles within the state is extended to the commercial zones as described by federal regulations concerning interstate commerce, 49 C.F.R. §1048.101, and to the interstate system as provided in 23 U.S.C. §127 and 49 U.S.C. §31112(c), as amended by Pub. L. No. 104-59.
f. A trailer or semitrailer, laden or unladen, shall not have an overall length in excess of fifty-three feet when operating in a truck tractor-semitrailer combination exclusive of retractable extensions used to support the load. However, when a trailer or semitrailer is used exclusively for the transportation of passenger vehicles, light delivery trucks, panel delivery trucks, pickup trucks, recreational vehicle chassis, or boats, the load carried on the trailer or semitrailer may extend up to three feet beyond the front bumper and up to four feet beyond the rear bumper of the trailer or semitrailer. A lowboy semitrailer, laden or unladen, which is designed and exclusively used for the transportation of construction equipment shall not have an overall length in excess of fifty-seven feet when used in a truck tractor-semitrailer combination.
g. A trailer or semitrailer, laden or unladen, shall not have an overall length in excess of twenty-eight feet six inches when operating in a truck tractor-semitrailer-trailer combination or truck tractor-semitrailer-semitrailer combination. When the semitrailers in a truck tractor-semitrailer-semitrailer combination are connected by a rigid frame extension including a fifth-wheel connection point attached to the rear frame of the first semitrailer, the length of the frame extension shall not be included when determining the overall length of the first semitrailer.
h. Power units designed to carry cargo, when used in combination with a trailer or semitrailer shall not exceed sixty-five feet in overall length for the combination exclusive of retractable extensions used to support the load. However, if a combination of vehicles is used exclusively for the transportation of passenger vehicles, light delivery trucks, panel delivery trucks, pickup trucks, recreational vehicle chassis, or boats, the load may extend up to three feet beyond the front bumper of the power unit and up to four feet beyond the rear bumper of the trailer or semitrailer.
i. A stinger-steered automobile transporter shall not have an overall length exceeding eighty feet, exclusive of retractable extensions used to support the load and all other devices or appurtenances related to the safe and efficient operation of the vehicle, except that the load may extend up to four feet beyond the front bumper and up to six feet beyond the rear bumper.
j. A motor home or motorsports recreational vehicle shall not have an overall length, excluding front and rear bumpers and safety equipment, in excess of forty-five feet.
k. A combination of two vehicles coupled together, one of which is a motor home, shall not have an overall length in excess of sixty-five feet.
l. A combination of two vehicles coupled together, one of which is a travel trailer or fifth-wheel travel trailer, shall not have an overall length in excess of sixty-five feet.
m. Notwithstanding any other provision of this chapter, and to the extent allowed under federal law, the maximum length of a towaway trailer transporter combination operated on the highways of this state is eighty-five feet. For purposes of this paragraph, “towaway trailer transporter combination” means a combination of vehicles consisting of a towing vehicle and two unladen trailers or unladen semitrailers in which the trailers or semitrailers constitute inventory property of the manufacturer intended for sale and which are being transported from a trailer manufacturer to a trailer distributor or authorized trailer dealer.
n. (1) Notwithstanding paragraph “g” or any other provision of this chapter, the department is authorized to adopt rules providing for economic export corridors for the transportation of goods or products manufactured in Iowa to or through the state of South Dakota and for the return of unladen semitrailers or unladen full trailers used for the transportation of those goods or products. The rules may authorize the operation of the following combinations of vehicles on an economic export corridor:
(a) A truck tractor-semitrailer-semitrailer converted to a full trailer by use of a dolly equipped with a fifth wheel which is considered a part of the trailer for all purposes, and not a separate unit.
(b) A truck tractor-semitrailer-full trailer.
(c) A truck tractor-semitrailer-semitrailer combination, where the semitrailers are connected by a rigid frame extension including a fifth wheel connection point attached to the rear frame of the first semitrailer. The length of the frame extension shall not be included when determining the overall length of the first semitrailer.
(2) Rules adopted pursuant to this paragraph “n” shall provide that combinations of vehicles authorized to operate on an economic export corridor shall meet all of the following requirements:
(a) The length of the combination of vehicles, excluding the length of the truck tractor, shall not exceed eighty-one and one-half feet.
(b) The length of either semitrailer or full trailer shall not exceed forty-five feet.
(c) The weight of the second semitrailer or full trailer shall not exceed the weight of the first semitrailer by more than three thousand pounds.
(d) The gross weight of the combination of vehicles shall not exceed eighty thousand pounds and the combination of vehicles shall not exceed the gross axle weight limits of section 321.463, subsection 2.
(e) The load on each semitrailer or full trailer in the combination shall be an indivisible load. For the purpose of issuing permits for height or width under chapter 321E, the combination of vehicles shall be considered an indivisible load so long as the load on each semitrailer or full trailer in the combination remains an indivisible load.
(3) An economic export corridor established by the department shall not include any segment of the interstate system or any part of the national network of highways identified pursuant to
23 C.F.R. pt. 658
. This subparagraph does not prohibit operation on any segment of the interstate system or part of the national network of highways that is permitted under paragraph “e”.
(4) For purposes of this paragraph “n”, “full trailer” means as defined in
49 C.F.R. §390.5
.
o. Notwithstanding any other provision of this chapter, and to the extent allowed under federal law, a combination of two vehicles coupled together, one of which is a motorsports recreational vehicle, shall not have an overall length in excess of eighty-five feet.
p. Notwithstanding any other provision of this chapter, and to the extent allowed under federal law, a vehicle or combination of vehicles transporting a divisible load of hay, straw, stover, or bagged livestock bedding shall not have an overall length in excess of seventy-five feet.
3. Fire fighting apparatus and vehicles operated during daylight hours when transporting poles, pipe, machinery, or other objects of a structural nature which cannot be readily disassembled when required for emergency repair of public service facilities or properties are not subject to the limitations on overall length of vehicles and combinations of vehicles imposed under this section. However, for operation during nighttime hours, these vehicles and the load being transported shall be equipped with a sufficient number of clearance lamps on both sides and marker lamps at the extreme ends of the projecting load to clearly mark the dimensions of the load. A member of the state patrol shall also be notified prior to the operation of the vehicle.
[C31, 35, §5067-d4; C39, §5035.06; C46, 50, 54, 58, 62, 66, 71, 73, 75, 77, 79, 81, §321.457; 82 Acts, ch 1056, §2, 3]
83 Acts, ch 9, §6 – 8; 83 Acts, ch 116, §2; 84 Acts, ch 1077, §1; 87 Acts, ch 186, §6 – 10; 88 Acts, ch 1208, §1; 89 Acts, ch 34, §2 – 5; 91 Acts, ch 31, §1, 2; 93 Acts, ch 87, §7; 94 Acts, ch 1087, §6, 7; 94 Acts, ch 1199, §78; 96 Acts, ch 1004, §1; 96 Acts, ch 1089, §2, 3; 96 Acts, ch 1219, §26; 98 Acts, ch 1074, §25; 98 Acts, ch 1075, §24; 2000 Acts, ch 1016, §16, 29; 2001 Acts, ch 32, §21, 22; 2001 Acts, ch 153, §15; 2001 Acts, ch 176, §80; 2005 Acts, ch 35, §31; 2006 Acts, ch 1068, §30, 31; 2007 Acts, ch 143, §16, 35; 2012 Acts, ch 1090, §1; 2012 Acts, ch 1138, §64; 2014 Acts, ch 1127, §14, 15; 2017 Acts, ch 46, §1; 2019 Acts, ch 23, §1; 2020 Acts, ch 1054, §3
Referred to in §321E.2, 321E.8, 321E.9, 321E.10, 321E.11, 321E.17, 321E.26, 321E.29B, 805.8A(12)(c)
For applicable scheduled fines, see §805.8A, subsection 12, paragraph c