Illinois Oversize Permits are valid for 5 days.
Permit loads on Expressways in Cook County are restricted to a maximum of 120,000 pounds, 12′ wide and/or 13’6″. Several special restrictions apply in Cook County, as listed on provision sheets (General Provisions B). Loads over 14’6″ wide up to and including 16′ wide are limited to the hours of 9:00 a.m. – 3:00 p.m. Monday through Friday in Cook, DuPage, Lake, Kane, Madison, McHenry, Monroe, St. Clair and Will counties. Over 16′ wide may have additional restrictions. No travel from noon the day prior to major holidays or holiday weekends. Maximum width is 12′ and maximum height is 14’6″.
Maximum gross weight allowed is 120,000. Length exceeding 100′ needs prior approval and special permit. Separate permits must be obtained from the Illinois State Toll Highway Authority.
Length limitations do not apply (over dimensional permit not needed) for vehicles operated in the daytime, Monday through Friday, when transporting beams, poles, pipe, culvert or other objects of a structural nature 80′ or less in length (overall length 100′ or less). Farm tractors and other implements of husbandry may be hauled without a permit during daylight hours (including weekends) when over width only. Illinois Oversize Permits is still needed if over 13’6 high, or overweight.
Maximum speed shall be 5 m.p.h. below the posted speed limit, EXCEPT when otherwise specified in the permit. Legal weight, legal height movements up to and including 10 feet wide are allowed to travel at the legal maximum speed limit.
The vehicle must have the following characteristics:
*Note: Kingpin to the center of rear axle not over 45’6″, or needs to be permitted.
*Note: Overweight applications get treated as superloads when: On 5 axles, grossing over 100,000 pounds and/or over 48,000 pounds on a tandem group. On 6 or more axles, grossing over 120,000 pounds and/or over 48,000 pounds on any axle group.
**Note on Lift or Pusher axles: Maximum weight variance between axles in a group is 2,000 pounds. Over 16′ wide or 17′ high will require a field or district engineering investigation. Over 17′ high, all overhead utility companies must be contacted and documentation must be provided
***Note: Maximum height on Chicago highways is 13’6″. No interstate routing is allowed for over 15’9” height. Height of 16′ or more requires detailed route survey.
*Note: Loads exceeding any two of the above dimensions – 2 escort pilot cars.
Flags are required on the extremities of all oversize vehicles or loads and all protruding objects. “Oversize Load” signs are required on loads over 10′ wide, 14’6 high and/or 75′ long. All oversize/overweight permit loads must display an operable oscillating, rotating or flashing amber light or lights on the tractor. Light(s) must be visible from both sides and the front, and must be strong enough to be seen for at least 500 feet in the daytime. When visibility of the light is blocked from the rear, and for loads over 80′ long or combinations over 100′ long require a second light mounted 10′ of rear of the object, as high as practical over it.