2022 Michigan State DOT Shipping Laws, Rules, Regulations, and Limitations for Oversize and Heavy-haul Trucking
Help others by sharing your knowledge of Michigan state regulations below.
Locate oversize, heavy-haul trucking permits:
Michigan oversize and heavy-haul trucking permits.
Do I Need a Trucking Permit? Legal Load Limits in Michigan
Michigan maximum load limits until a trucking permit are required:
- Length: Overall no longer than 75 feet on designated highways. The trailer length maximum is 50 feet on non-designated and 53 feet on designated.
- Width: 96 inches on non-designated highways and 102 inches (8 feet 6 inches.) on designated.
- Height: 13 feet 6 inches tall.
- Weight: 80,000 pounds GVW, 20,000 pounds on single axles (not steer), 34,000 pounds on tandem axles.
- Overhang: 3 feet in the front and anything over 4 feet in the rear must be red flagged in the day and have a red light at night.
NOTES: There’s no restriction on the maximum length of the combination of truck-tractor and semitrailer with or without load
Routine Oversize and Heavy-haul Trucking Permits in Michigan
These maximum dimensions/weights are considered routine oversize or heavy-haul trucking permits in Michigan:
- Length: Under 150 feet in length. Anything over 150 feet is classified as a superload (105 feet maximum for mobile homes).
- Width: Figure up to 16 feet as a routine permit. Anything over is going to look at seriously and they may even classify you as superload.
- Height: Up to 15 feet is routine. If you are over 15 feet high count on needing a route survey.
- Weight: All weights in excess of 80,000 pounds overall are decided on a case-by-case basis. Anything over 150,000 lbs is subject to a bridge weight study.
- Overhang: Any shipment in excess of 4 feet of the overhang is permitted on a case-by-case basis only.
NOTES: Maximum speed for any permitted shipment is 45 MPH. Permits for heavy shipments may take more than 10 days to process.
Maximum Legal Dimensions in Michigan
- Width: 96 inches.
- Width: 102 inches on non-designated roads.
- Height: 13 feet, 6 inches
- Length of semitrailer: 53 feet including the load.
- Length of a semitrailer: 50 feet including the load on non-designated roads.
- Length of a combination of truck-tractor and semitrailer with or without load: They say there are no limitations.
- Length of any other vehicle with or without load: 40 feet – bumpers are not included in measurements.
- Units permitted in train: 2 semi-trailers maximum.
- Length of a combination: 65 feet. Semitrailers longer than 50 feet shall have a wheelbase of 37 feet to 41 feet (measured from the kingpin coupling to the center of the axles or to the center of the tandem axle assembly if equipped with 2 axles). Semitrailers longer than 50 feet are limited to 3 axles. Semitrailers longer than 50 feet shall operate on designated highways only. Semitrailers and trailers shall be measured from the front vertical plane of the foremost transverse load supporting structure to the rearmost transverse load supporting structure.
NOTE: Length shall not include safety and energy conservation devices including, but not limited to, impact-absorbing bumpers, rearview mirrors, turn signal lamps, marker lamps, steps, and handholds for entry and egress, flexible fender extensions, mud flaps or splash and suppressant devices, load-induced tire bulge, refrigeration or heating units, or air compressors. A device shall be excluded from a determination of length only if it is not designed or used for the carrying of cargo.
- Projection beyond the front of vehicles: 3 feet
- Overhang beyond the rear of vehicles: Any amount is permissible if the legal length is not exceeded. However, if this overhang is 4 feet or more, there shall be displayed on the extreme rear of such a load a 12-inch red flag that is square in the daytime and a red light or lantern at night.
- Axle limitation: A combination of vehicles shall not exceed 11 axles.
- Width: Unprocessed Logs, Pulpwood, Wood Bolts, Agricultural Products, and Concrete Pipe, (108 inches for load only), Busses, (102 inches), Implements of Husbandry: A person may only operate or tow an implement of husbandry of any width on a highway as required for normal farming operations.
- Length: Truck-Tractor, Semitrailer, and Trailer or Truck-Tractor and 2 Semitrailers: No overall length limitation providing the length of each semitrailer and trailer including load does not exceed 28 feet 6 inches or the overall length of the semitrailer and trailer or 2 semitrailers as measured from the front of the first towed unit to the rear of the second towed unit while the units are coupled together does not exceed an overall length of 58 feet, including load. Any such combination, except as herein described with regard to assembled motor vehicles or bodies, recreational vehicles, or boats, may be operated only on such highways and routes as designated by the appropriate authorities.
- Truck and trailer: Overall length not to exceed 65 feet. Any such combination may be operated only on such highways and routes as designated by the appropriate authorities.
Truck and trailer note: Designed and used to transport saw logs, pulpwood, and tree length poles. Overall length is not to exceed 70 feet including load. Any such combination may be operated only on such highways and routes as designated by the appropriate authorities. Truck and trailer designed and used exclusively to transport assembled motor vehicles or bodies, recreational vehicles, or boats: Any such combination not to exceed a total length of 65 feet, except a stinger-steered combination shall not exceed a total length of 75 feet. The load on any such combination of vehicles may extend an additional 3 feet beyond the front and 4 feet beyond the rear of the combination of vehicles.
Michigan Superloads Information
Information about shipping superloads in Michigan.
If your shipment is in excess of any of the following weights or dimensions it may be classified as a superload.
- Length: Anything over 150 feet.
- Width: 16 feet or over.
- Height: 15 feet and over is classified as a superload. Some limited routes may vary.
NOTES: We have no weight maximums to report. Height may be on a case-by-case basis.
Lights, Safety Flags, and Warning Signs for Heavy Haul and Oversize Loads in Michigan
Required safety markings, flags, and warning lights for heavy haul and oversize loads in Michigan:
All oversize load shipments will be required to display 2 “Oversize Load” signs. One must be mounted to the truck’s bumper and the other to the rear of the trailer. Signs must be a minimum of 7 feet in width and 18 inches in height with 10-inch black letters on a yellow background. The flags are required on all 4 corners of the combination and are red or orange and 18 inches square. If the item being shipped has dimensions extending beyond the trailer, then the extremities must be flagged. Headlights must be on at all times. In addition, a minimum of 2 flashing strobing lights must be mounted to the rear portion of the load.
When Pilot Cars or Escort Vehicles Are Required in Michigan
Heavy-haul or oversize loads may require to be accompanied by an escort vehicle or pilot car if:
- Length: 90 feet to 100 feet one on the rear. Over 100 feet requires a rear pilot car or “chase” escort vehicle.
- Width: Loads over 12 wide on 4 lanes are required for one rear escort/pilot car. A lead or front pilot car is required for loads on 2 lane highway over 12 feet wide. Front and rear pilot cars/escorts are required for loads over 14 feet wide.
- Height: Over 14 feet and 5 inches is required to have a pilot car equipped with a height pole. Over 15 feet in height will require a rear chase escort vehicle in addition to 1 lead pilot car equipped with a height pole.
- Overhang: If over 15 feet 1 rear escort is required.
- Weight: If the truck can maintain minimum speeds no pilot cars are required unless excessive or superload.
NOTE: Allow 1 to 10 days for permits to be approved. Distance for a pilot car to lead/chase load 500′ unless otherwise stated on the permit. This is the distance between the lead/chase and the truck/trailer. Maximum speeds of 45 MPH if 4 or more lanes, 35 MPH is under 4 lanes. Also, read the travel restrictions below.
Pilot Cars/Escort Vehicle Certifications in Michigan
Pilot car or escort vehicle mandatory operator certifications and vehicle requirements:
To qualify as a pilot car vehicle in Michigan, you must either have a pickup truck or a passenger car with at least one rotating or flashing amber light mounted on the top of the vehicle. Pilot cars and escort vehicles must also display one oversize load sign that is 5′ x 1′ tall and has black letters no less than 8 inches tall on a yellow background. All flashing, stroking, or rotating amber lights must be visible from 500 feet. In addition to this, we strongly suggest pilot cars and escort vehicles have the minimum of federally suggested equipment.
Legal Travel Times for Oversize and Heavy Haul Loads in Michigan
Travel times and restrictions for heavy-haul and oversize loads in Michigan:
Travel time is sunrise to sunset with the half hour before sunrise and a half hour after sunset leniency rule. No weekend travel. No holiday travel or the day after Christmas or Thanksgiving. Many counties have rush hour rules from 7:00 AM to 9:00 AM and 3:00 PM to 6:00 PM (look at the permit). Wind restrictions if over 24 MPH, you can’t run—Frost and thaw laws in effect from Feb until April on weight. You can view holiday restrictions.
Michigan DOT Contact Information, Notes, and Resources
Michigan DOT contact information:
Michigan Department of Transportation – DOT, Permits Unit
425 West Ottowa Street
Lansing, MI 48909
Email: click here for an e-mail contact form on the state website.
Hours: Monday thru Friday 7:30 AM – 4:30 PM (closed from 12 until 1:00 PM)
Eastern Standard Time
Michigan is a member of MVCSHTO.
The information contained in these pages is research information primarily for use by oversize and overweight trucking company drivers, dispatchers, and pilot car companies. While every effort is put into maintaining the accuracy of this information you must absolutely verify this information with the Michigan State DOT Permits office before commencing movement.