625 ILCS 5/15-111
2021 Illinois Compiled Statutes|Chapter 625 - VEHICLES|625 ILCS 5/ - Illinois Vehicle Code.|Chapter 15 - Size, Weight, Load And Permits

 (from Ch. 95 1/2, par. 15-111)Sec. 15-111. Wheel and axle loads and gross weights.(a) No vehicle or combination of vehicles    with pneumatic tires may be operated, unladen or with load,  when the total weight on the road surface  exceeds the following: 20,000 pounds on a single axle; 34,000 pounds on a tandem axle with  no axle within the tandem exceeding 20,000 pounds; 80,000  pounds gross weight for vehicle combinations of 5 or more axles;  or a total weight on a group of 2 or more consecutive axles in excess of that  weight produced by the application of the following formula:  W = 500 times the  sum of (LN divided by N-1) + 12N + 36, where "W" equals overall total weight on  any group of 2 or more consecutive axles to the nearest 500 pounds, "L" equals  the  distance measured to the nearest foot between extremes of any group of 2 or  more consecutive axles, and "N" equals the number of axles in the group under  consideration.The above formula when expressed in tabular form results in allowable loads  as follows:  Distance measuredto the nearestfoot between theextremes of any         Maximum weight in poundsgroup of 2 or           of any group ofmore consecutive        2 or more consecutive axlesaxles    feet 2 axles 3 axles 4 axles 5 axles 6 axles   4 34,000   5 34,000   6 34,000   7 34,000   8  34,000* 34,000 Between 8  and 938,000 42,000   9 39,000 42,500   10 40,000 43,500   11  44,000   12  45,000 50,000   13  45,500 50,500   14  46,500 51,500   15  47,000 52,000   16  48,000 52,500 58,000   17  48,500 53,500 58,500   18  49,500 54,000 59,000   19  50,000 54,500 60,000   20  51,000 55,500 60,500 66,000   21  51,500 56,000 61,000 66,500   22  52,500 56,500 61,500 67,000   23  53,000 57,500 62,500 68,000   24  54,000 58,000 63,000 68,500   25  54,500 58,500 63,500 69,000   26  55,500 59,500 64,000 69,500   27  56,000 60,000 65,000 70,000   28  57,000 60,500 65,500 71,000   29  57,500 61,500 66,000 71,500   30  58,500 62,000 66,500 72,000   31  59,000 62,500 67,500 72,500   32  60,000 63,500 68,000 73,000   33   64,000 68,500 74,000   34   64,500 69,000 74,500   35   65,500 70,000 75,000   36   66,000** 70,500 75,500   37   66,500** 71,000 76,000   38   67,500** 72,000 77,000   39   68,000 72,500 77,500   40   68,500 73,000 78,000   41   69,500 73,500 78,500   42   70,000 74,000 79,000   43   70,500 75,000 80,000   44   71,500 75,500   45   72,000 76,000   46   72,500 76,500   47   73,500 77,500   48   74,000 78,000   49   74,500 78,500   50   75,500 79,000   51   76,000 80,000   52   76,500   53   77,500   54   78,000   55   78,500   56   79,500   57   80,000    *If the distance between 2 axles is 96 inches or less, the 2 axles are  tandem axles and the maximum total weight may not exceed 34,000 pounds,  notwithstanding the higher limit resulting from the application of the formula.  **Two consecutive sets of tandem axles may carry 34,000 pounds each if the overall distance between the first and last axles of these tandems is 36 feet or more.Vehicles not in a combination having more than 4 axles may not exceed the  weight in the table in this subsection (a)  for 4 axles measured between the  extreme axles of the  vehicle.Vehicles in a combination having more than 6 axles may not exceed the weight  in the table in this subsection (a)  for 6 axles measured between the extreme  axles of the  combination.Local authorities, with respect  to streets and highways under their jurisdiction, without additional  fees, may also by ordinance or resolution allow the weight limitations of this  subsection, provided the maximum gross weight on any one axle shall not exceed  20,000 pounds and the maximum total weight on any tandem axle  shall not exceed  34,000 pounds, on designated highways when appropriate regulatory signs giving  notice are erected upon the street or highway or portion of any street or  highway affected by the ordinance or resolution.The following are exceptions to the above formula:(1) Vehicles for which a different limit is     established and posted in accordance with Section 15-316 of this Code.(2) Vehicles for which the Department of     Transportation and local authorities issue overweight permits under authority of Section 15-301 of this Code.  These vehicles are not subject to the bridge formula.(3) Cities having a population of more than 50,000     may permit by ordinance axle loads on 2-axle motor vehicles 33 1/2% above those provided for herein, but the increase shall not become effective until the city has officially notified the Department of the passage of the ordinance and shall not apply to those vehicles when outside of the limits of the city, nor shall the gross weight of any 2-axle motor vehicle operating over any street of the city exceed 40,000 pounds.(4) Weight limitations shall not apply to vehicles     (including loads) operated by a public utility when transporting equipment required for emergency repair of public utility facilities or properties or water wells.(4.5) A 3-axle or 4-axle vehicle (including when     laden) operated or hired by a municipality within Cook, Lake, McHenry, Kane, DuPage, or Will county being operated for the purpose of performing emergency sewer repair that would be subject to a weight limitation less than 66,000 pounds under the formula in this subsection (a) shall have a weight limitation of 66,000 pounds or the vehicle's gross vehicle weight rating, whichever is less. This paragraph (4.5) does not apply to vehicles being operated on the National System of Interstate and Defense Highways, or to vehicles being operated on bridges or other elevated structures constituting a part of a highway.(5) Two consecutive sets of tandem axles may carry a     total weight of 34,000 pounds each if the overall distance between the first and last axles of the consecutive sets of tandem axles is 36 feet or more, notwithstanding the lower limit resulting from the application of the above formula.(6) A truck, not in combination and used exclusively     for the collection of rendering materials, may, when laden, transmit upon the road surface, except when on part of the National System of Interstate and Defense Highways, the following maximum weights: 22,000 pounds on a single axle; 40,000 pounds on a tandem axle.(7) A truck not in combination, equipped with a self     compactor or an industrial roll-off hoist and roll-off container, used exclusively for garbage,  refuse, or recycling operations, may, when laden, transmit upon the road surface, except when on part of the National System of Interstate and Defense Highways, the following maximum weights: 22,000 pounds on a single axle; 40,000 pounds on a tandem axle; 40,000 pounds gross weight on a 2-axle vehicle; 54,000 pounds gross weight on a 3-axle vehicle. This vehicle is not subject to the bridge formula.(7.5) A 3-axle rear discharge truck mixer registered     as a Special Hauling Vehicle, used exclusively for the mixing and transportation of concrete in the plastic state, may, when laden, transmit upon the road surface, except when on part of the National System of Interstate and Defense Highways, the following maximum weights: 22,000 pounds on single axle; 40,000 pounds on a tandem axle; 54,000 pounds gross weight on a 3-axle vehicle. This vehicle is not subject to the bridge formula.(8) Except as provided in paragraph (7.5) of this     subsection (a), tandem axles on a 3-axle truck registered as a Special Hauling Vehicle, manufactured prior to or in the model year of 2024 and first registered in Illinois prior to January 1, 2025, with a distance greater than 72 inches but not more than 96 inches between any series of 2 axles, is allowed a combined weight on the series not to exceed 36,000 pounds and neither axle of the series may exceed 20,000 pounds.  Any vehicle of this type manufactured after the model year of 2024 or first registered in Illinois after December 31, 2024 may not exceed a combined weight of 34,000 pounds through the series of 2 axles and neither axle of the series may exceed 20,000 pounds.A 3-axle combination sewer cleaning jetting vacuum     truck registered as a Special Hauling Vehicle, used exclusively for the transportation of non-hazardous solid waste, manufactured before or in the model year of 2014, first registered in Illinois before January 1, 2015, may, when laden, transmit upon the road surface, except when on part of the National System of Interstate and Defense Highways, the following maximum weights: 22,000 pounds on a single axle; 40,000 pounds on a tandem axle; 54,000 pounds gross weight on a 3-axle vehicle. This vehicle is not subject to the bridge formula.(9) A 4-axle truck mixer registered as a Special     Hauling Vehicle, used exclusively for the mixing and transportation of concrete in the plastic state, and not operated on a highway that is part of the National System of Interstate Highways, is allowed the following maximum weights: 20,000 pounds on any single axle; 36,000 pounds on a series of axles greater than 72 inches but not more than 96 inches; and 34,000 pounds on any series of 2 axles greater than 40 inches but not more than 72 inches. The gross weight of this vehicle may not exceed the weights allowed by the bridge formula for 4 axles.  The bridge formula does not apply to any series of 3 axles while the vehicle is transporting concrete in the plastic state, but no axle or tandem axle of the series may exceed the maximum weight permitted under this paragraph (9) of subsection (a).(10) Combinations of vehicles, registered as Special     Hauling Vehicles that include a semitrailer manufactured prior to or in the model year of 2024, and registered in Illinois prior to January 1, 2025, having 5 axles with a distance of 42 feet or less between extreme axles, may not exceed the following maximum weights: 20,000  pounds on a single axle; 34,000  pounds on a tandem axle; and 72,000 pounds gross weight. This combination of vehicles is not subject to the bridge formula.  For all those combinations of vehicles that include a semitrailer manufactured after the effective date of P.A. 92-0417, the overall distance between the first and last axles of the 2 sets of tandems must be 18 feet 6 inches or more. Any combination of vehicles that has had its cargo container replaced in its entirety after December 31, 2024 may not exceed the weights allowed by the bridge formula.(11) The maximum weight allowed on a vehicle with     crawler type tracks is 40,000 pounds.(12) A combination of vehicles, including a tow truck     and a disabled vehicle or disabled combination of vehicles, that exceeds the weight restriction imposed by this Code, may be operated on a public highway in this State provided that neither the disabled vehicle nor any vehicle being towed nor the tow truck itself shall exceed the weight limitations permitted under this Chapter. During the towing operation, neither the tow truck nor the vehicle combination shall exceed 24,000 pounds on a single rear axle and 44,000 pounds on a tandem rear axle, provided the towing vehicle:(i) is specifically designed as a tow truck         having a gross vehicle weight rating of at least 18,000 pounds and is equipped with air brakes, provided that air brakes are required only if the towing vehicle is towing a vehicle, semitrailer, or tractor-trailer combination that is equipped with air brakes;(ii) is equipped with flashing, rotating, or         oscillating amber lights, visible for at least 500 feet in all directions;(iii) is capable of utilizing the lighting and         braking systems of the disabled vehicle or combination of vehicles; and(iv) does not engage in a tow exceeding 20 miles         from the initial point of wreck or disablement. Any additional movement of the vehicles may occur only upon issuance of authorization for that movement under the provisions of Sections 15-301 through 15-318 of this Code. The towing vehicle, however, may tow any disabled vehicle to a point where repairs are actually to occur. This movement shall be valid only on State routes. The tower must abide by posted bridge weight limits.(12.5) The vehicle weight limitations in this Section     do not apply to a covered heavy duty tow and recovery vehicle. The covered heavy duty tow and recovery vehicle license plate must cover the operating empty weight of the covered heavy duty tow and recovery vehicle only.(13)   Upon and during a declaration of an emergency     propane supply disaster by the Governor under Section 7 of the Illinois Emergency Management Agency Act:(i)   a truck not in combination, equipped with a         cargo tank, used exclusively for the transportation of propane or liquefied petroleum gas may, when laden, transmit upon the road surface, except when on part of the National System of Interstate and Defense Highways, the following maximum weights: 22,000 pounds on a single axle; 40,000 pounds on a tandem axle; 40,000 pounds gross weight on a 2-axle vehicle; 54,000 pounds gross weight on a 3-axle vehicle; and(ii)   a truck when in combination with a trailer         equipped with a cargo tank used exclusively for the transportation of propane or liquefied petroleum gas may, when laden, transmit upon the road surface, except when on part of the National System of Interstate and Defense Highways, the following maximum weights: 22,000 pounds on a single axle; 40,000 pounds on a tandem axle; 90,000 pounds gross weight on a 5-axle or 6-axle vehicle.Vehicles operating under this paragraph (13) are not     subject to the bridge formula.(14)      A vehicle or combination of vehicles that     uses natural gas or propane gas as a motor fuel may exceed the above weight limitations by up to 2,000 pounds, the total allowance is calculated by an amount that is equal to the difference between the weight of the vehicle attributable to the natural gas or propane gas tank and fueling system carried by the vehicle, and the weight of a comparable diesel tank and fueling system.  This paragraph (14) shall not allow a vehicle to exceed any posted weight limit on a highway or structure.(15) An emergency vehicle or fire apparatus that is a     vehicle designed to be used under emergency conditions to transport personnel and equipment, and used to support the suppression of fires and mitigation of other hazardous situations on a Class I highway,   may not exceed 86,000 pounds gross weight, or any of the following weight allowances:(i) 24,000 pounds on a single steering axle;(ii) 33,500 pounds on a single drive axle;(iii) 62,000 pounds on a tandem axle; or(iv) 52,000 pounds on a tandem rear drive steer         axle.(16) A bus, motor coach, or recreational vehicle may     carry a total weight of 24,000 pounds on a single axle, but may not exceed other weight provisions of this Section.Gross weight limits shall not apply to the combination of the tow truck  and vehicles being towed.  The tow truck license plate must cover the  operating empty weight of the tow truck only. The weight  of each vehicle being towed shall be covered by a valid license plate issued to  the owner or operator of the vehicle being towed and displayed on that vehicle.  If no valid plate issued to the owner or operator of that vehicle is displayed  on that vehicle, or the plate displayed on that vehicle does not cover the  weight of the vehicle, the weight of the vehicle shall be covered by  the third tow truck plate issued to the owner or operator of the tow truck and  temporarily affixed to the vehicle being towed. If a roll-back carrier is registered and being used as a tow truck, however, the license plate or plates for the tow truck must cover the gross vehicle weight, including any load carried on the bed of the roll-back carrier.The Department may by rule or regulation prescribe additional requirements.  However, nothing in this Code shall prohibit a tow truck under  instructions of a police officer from legally clearing a disabled vehicle,  that may be in violation of weight limitations of this Chapter, from the  roadway to the berm or shoulder of the highway.  If in the opinion of the police officer that location is unsafe, the officer  is authorized to have the disabled vehicle towed to the nearest place of  safety.For the purpose of this subsection, gross vehicle weight rating, or  GVWR, means the value specified by the manufacturer as the loaded  weight of the tow truck.(b) As used in this Section, "recycling haul" or "recycling operation" means the hauling of non-hazardous, non-special, non-putrescible materials, such as paper, glass, cans, or plastic, for subsequent use in the secondary materials market.(c) No vehicle or combination of vehicles equipped with pneumatic tires  shall be operated, unladen or with load, upon the highways of this State in  violation of the provisions of any permit issued under the provisions of  Sections 15-301 through 15-318 of this Chapter.(d) No vehicle or combination of vehicles equipped with other than pneumatic  tires may be operated, unladen or with load, upon the highways of this State  when the gross weight on the road surface through any wheel exceeds 800  pounds per inch width of tire tread or when the gross weight on the road  surface through any axle exceeds 16,000 pounds.(e) No person shall operate a vehicle or combination of vehicles over  a bridge or other elevated structure constituting part of a highway with a  gross weight that is greater than the maximum weight permitted by the  Department, when the structure is sign posted as provided in this Section.(f) The Department upon request from any local authority shall, or upon  its own initiative may, conduct an investigation of any bridge or other  elevated structure constituting a part of a highway, and if it finds that  the structure cannot with safety to itself withstand the weight of vehicles  otherwise permissible under this Code the Department shall determine and  declare the maximum weight of vehicles that the structures can withstand,  and shall cause or permit suitable signs stating maximum weight to be  erected and maintained before each end of the structure.  No person shall  operate a vehicle or combination of vehicles over any structure with a  gross weight that is greater than the posted maximum weight.(g) Upon the trial of any person charged with a violation of subsection  (e) or (f) of this Section, proof of the determination of the maximum  allowable weight by the Department and the existence of the signs,  constitutes conclusive evidence of the maximum weight that can be  maintained with safety to the bridge or structure.      (Source: P.A. 102-124, eff. 7-23-21.)