The following information about Michigan Oversize Permits is for informational purposes only. It’s important to always read your permits and provisions sheets carefully as we cannot guarantee the accuracy of the information provided. If you have any questions or need assistance, you can contact the following number.

Michigan DOT #: 517-241-8999

Michigan Oversize Permits Duration

Michigan oversize permits remain valid for a duration of five travel days, and it is essential to obtain the permit before entering the state.te.

Operating Time

Travel is permitted from sunrise to sunset. As part of a trial initiative, weekend travel is now allowed for loads that do not exceed 10 feet in width, 14 feet in height, and 90 feet in length. Specifically, travel is sanctioned on Saturdays and Sundays until 3:00 pm. Additionally, if a load is overweight but complies with all legal dimensions and does not exceed an overall length of 70 feet, continuous travel is permitted.

Restricted Travel in Michigan

In the specified counties of Genesee, Ingham, Jackson, Kalamazoo, Kent, Muskegon, Macomb, Oakland, Saginaw, Westenau, and Wayne, loads exceeding 12 feet in width or 90 feet in length are prohibited from moving between 7:00 am – 9:00 am and from 3:00 pm – 6:00 pm. Additionally, no travel is allowed on major holidays and holiday weekends.

Bridge Crossing in Michigan

Contact the Mackinaw Bridge Authority at least 24 hours before your planned bridge arrival or crossing by calling 906-643-7600. An escort will be provided at no charge for loads exceeding legal weight or 10 feet in width. Crossing is not permitted when winds exceed 25 miles per hour.

For the Ambassador Bridge, which connects Detroit and Windsor, Ontario, there is now a charge of $50.00 or more for oversized shipments, and a one-day notice may be required. Crossing hours are restricted from 10:00 am to 4:00 pm, Monday through Friday. You can reach the Ambassador Bridge at 313-496-1111.

Call (832) 454-5883 For Permit Consultation

Legal Dimensions for Michigan Oversize Load Permits


  • 53′ semi-trailer on Interstate and designated highways
  • 53′ trailer must have kingpin setting of 41′
  • 50′ maximum on non-designated highways


  • 8′-6″ designated highways
  • 8′ all other roads




80,000 Gross

  • Steer Axle – 700 pounds per inch of tire width (15,400 pounds with 11″ tires)
  • Tandem – 34,000 (32,000 on non-designated roads, and 26,000 on second tandem)
  • Tridem – 42,000 (39,000 on non-designated) Single – 20,000 designated highways (18,000 other roads)

Routine Permit Limits at Michigan




16′ (or 14′ during spring thaw restrictions)


15′ Shipper/driver are responsible for finding safe routes when the height exceeds 13’6″


Evaluated individually. Air or lift axles must be in the down position. Registration must cover at least the permitted weight for Michigan.

Loads exceeding these dimensions must be applied for as superloads, and may take up to ten days to issue once shipper letter, route surveys, etc. are received.

Michigan Oversize permits image

Escort Requirements for Michigan Oversize Permits


  • Over 90′ – one escort
  • Over 100′ – two escorts


Over 15′ – one escort.


  • Over 12′ – one escort
  • Over 14′ – two escorts


Lift Axles

As per the Michigan provision sheet, “Vehicles must have air or lift axles on the ground.” The permit office states that when under a load, all axles, including flip axles, must be on the ground if the vehicle is overweight.

Seasonal Load Restrictions

Typically, from February to April, axle weights and specific routing may undergo variations. No overweight permits will be granted during the spring weight restriction period. Maximum axle weights could be reduced by up to 35%. In certain cases, a tandem group may be limited to 26,000 pounds (13,000 pounds per axle). Alternatively, with two tandem groups, one group may be allowed 26,000 pounds, and the other tandem group may be permitted up to 32,000 pounds. For information related to frost restrictions, contact Frost Phone at 800-787-8960.

Signs, Flags & Lights for Michigan Oversize Permits

For any over dimensional load, “Oversize Load” signs are mandatory on the front of the vehicle and the rear of the load. An over width or overlength vehicle/load necessitates flags at each corner of the load, with an extra flag at the widest point on each side if it extends beyond the corner flags. When the rear overhang is 4 feet or more, the extreme rear of the load must have a flag for daytime running and a red light or lantern at night.