Wisconsin Department of Transportation

Alert: The following services will be unavailable on Saturday, January 5, 2013 from 12 a.m. (midnight) to 6 a.m. CST due to system maintenance.

Implements of Husbandry (IoH)

Width | Height | Length | Weight | Trailering | Other changes

Definition

The current definition of implements of husbandry (IoH) s.340.01(24)(a), Wis. Stat. is:

  1. A self-propelled or towed vehicle that is manufactured, designed or reconstructed to be used and that is exclusively used in the conduct of agricultural operations. An “implement of husbandry" may include any of the following:

    a. A farm tractor. (Referred to as Category A)

    b. A self-propelled combine; a self-propelled forage harvester; self-propelled fertilizer or pesticide application equipment but not including manure application equipment; towed tillage, planting, harvesting and cultivation equipment and its towing farm tractor or other power unit; or another self-propelled vehicle that directly engages in harvesting farm products, directly applies fertilizer, spray, or seeds but not manure, or distributes feed to livestock. (Referred to as Category B)

    c. A farm wagon, grain cart, farm trailer, manure trailer, or trailer adapted to be towed by, or to tow or pull, another implement of husbandry. (Referred to as Category C)

  2. A combination of vehicles in which each vehicle in the vehicle combination is an implement of husbandry as described in subd. 1. or in which an implement of husbandry described in subd. 1. c. is towed by a farm truck, farm truck tractor, motor truck or agricultural commercial motor vehicle.

       (b) "Implement of husbandry" does not include any of the following:

    1. An agricultural commercial motor vehicle.
    2. A vehicle that, notwithstanding s. 340.01 (8), is a commercial motor vehicle under 49 CFR 390.5

IoH Dimensions

Width

  • No width limitations however additional lighting and marking requirements are effective Nov. 1, 2015.
  • Also applies for IoH being operated or transported for delivery, service, or repair by dealer or farmer within 75-mile radius of business or farm.

Height

  • No height limitations.
  • Operator of IoH remains responsible for ensuring safe clearance of any overhead obstructions.

Length

  • Single vehicle
    • 60 feet
    • No-Fee permit may be required over 60 feet
  • Two vehicle combination
    • 100 feet
    • No-Fee permit may be required over 100 feet
  • Three vehicle combination
    • No more than 100 feet with speed restriction of 25 mph or less OR 70 feet at a speed greater than 25 mph.
    • No-Fee permit may be required if exceeding 100 feet in length.
    • Towed units being drawn by a motor truck, truck tractor, or Ag CMV must be empty. “Empty” means less than 20 percent full.
    • Length limits also apply to IoH being operated or transported for delivery, service, repair by dealer or farmer within 75-mile radius of business or farm. Beyond these dimensions, standard commercial (single or annual) permits are required.
  • There is no length limit for an irrigation system being towed by a farm tractor, farm truck, farm truck tractor or motor truck temporarily operated upon a highway. (s. 348.07 (2)(e)3., Wis. Stats.)

To operate at lengths greater than those listed above, you may need to apply for an IoH/Ag CMV Permit from the maintaining authority for the roads on which you are proposing to operate.

Weight

  • Maximum IoH/Ag CMV weight limits table applies. This allows for a maximum single axle weight of 23,000 pounds and a gross vehicle weight of 92,000 pounds dependent on number of axles and axle spacing. These weight limits pertain for all IoH on state and US highways.
  • No-Fee permit may be required if gross vehicle weight or axle weight is greater than the IoH weight table.
  • All operators must abide by seasonal or other special postings.
  • IoH weight limits do not apply on Interstate highways. §348.15 (9)(c)2.(d)
  • Exemptions
    • Empty potato harvester is exempt from axle weight limit. Also exempt from Class B road postings.
    • Category B is:
      • Exempt from axle weight limits on local roads unless local goverment authority passes ordinance or resolution limiting self-propelled IoH axle weight.
      • Exempt from gross vehicle weight and axle weight limits when operating between fields and operated on the highway for a distance of 1/2 mile or less.
      • Exempt from Class B road postings.
    • IoH traveling for delivery, service, repair by dealer or farmer within 75-mile radius of business or farm is exempt from gross vehicle weight and axle weight limits. Also exempt from Class B road postings.

To operate at weights greater than those listed above, you may need to apply for an IoH/Ag CMV Permit from the maintaining authority for the roads on which you are proposing to operate.

Trailering IoH

Act 15 allows operators to transport IoH on trailers or semi-trailers from farm to field, field to field and farm to farm under the same weight and dimension limits that are allowable for the IoH being transported. Please refer to the height, length, width and weight sections listed above. If the 2-vehicle combination transporting an IoH exceeds the IoH length, axle weight or gross weight limit, the operator may apply for a no-fee permit.

NOTE: No permit is needed to transport a wide IoH in daylight hours, but all lighting and marking regulations apply as if the IoH were being operated on the road.

Other changes

  • IoH are allowed to operate on the road with rubber tracks as long as it does not damage the highway
  • Limits on hours of operation are eliminated.
  • As of Nov. 1, 2015:
    • All vehicles exceeding 15-feet must have front and rear warning lights on and reflective material visible anytime on highway, unless operating in daylight with an escort vehicle and two orange or red flags marking the outside edges.
    • All vehicles exceeding 22 feet must have an escort vehicle with hazard flashers activated. Escort is not required for incidental travel of 1/2 mile or less.

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