SEASONAL LOAD RESTRICTIONS

When restricted loadings are in effect:

Rigid Pavements:

  • • Normal maximum axle weights reduced 25%
  • • Maximum wheel load: 525 lbs per inch of tire width

Flexible Pavements:

  • • Normal maximum axle weights reduced 35%
  • • Maximum wheel load: 450 lbs per inch of tire width

Maximum Overall Dimensions

Width

96 inches

102 inches on designated highways

Height

13 feet, 6 inches

Semitrailer Length (with load)

53 feet

50 feet on non-designated highways

Other Vehicle Length

40 feet

Excluding impact absorbing bumpers

Combination Length

65 feet

Truck-tractor + semitrailer + trailer

Axle Limitation

11 axles max

Combination of vehicles

Additional Requirements for Semitrailers Longer than 50 feet:

  • •Wheelbase of 37 to 41 feet (kingpin to center of axles/tandem assembly)
  • •Limited to 3 axles
  • •Operate on designated highways only

Projections & Overhang:

  • • Front projection: 3 feet maximum
  • • Rear overhang: Any amount if legal length not exceeded
  • • If rear overhang is 4 feet or more: 12-inch red square flag (daytime) and red light/lantern (night)

Maximum Allowable Axle Loadings

Spacing Between Axles Normal Loadings (55 MPH)
Vehicles >80,000 lbs		 Normal Loadings (55 MPH)
Vehicles ≤80,000 lbs		 Seasonal (35 MPH)
Rigid		 Seasonal (35 MPH)
Flexible
9 feet or over 18,000 lbs 20,000 lbs 13,500 lbs 11,700 lbs
More than 3½ ft but less than 9 ft 13,000 lbs 13,000 lbs 9,750 lbs 8,450 lbs
Tandem axle assembly *16,000 lbs 34,000 lbs on tandem **12,000 lbs ***10,400 lbs
Less than 3½ feet 9,000 lbs 9,000 lbs 6,750 lbs 5,850 lbs
Max wheel load (lbs/inch tire width) 700 lbs 700 lbs 525 lbs 450 lbs

* On any legal combination exceeding 80,000 lbs, only ONE tandem axle assembly permitted at 16,000 lbs per axle; others limited to 13,000 lbs per axle. When ≤80,000 lbs, TWO tandem assemblies permitted at 16,000 lbs per axle.

** On any legal combination exceeding 80,000 lbs, only ONE tandem axle assembly permitted at 12,000 lbs per axle; others limited to 9,750 lbs per axle. When ≤80,000 lbs, TWO tandem assemblies permitted at 12,000 lbs per axle.

*** On any legal combination exceeding 80,000 lbs, only ONE tandem axle assembly permitted at 10,400 lbs per axle; others limited to 8,450 lbs per axle. When ≤80,000 lbs, TWO tandem assemblies permitted at 10,400 lbs per axle.

Gross Vehicle Weight Limit

Maximum: 80,000 lbs

Plus the following formula for consecutive axle groups:

W = 500 × (LN/(N-1) + 12N + 36)

Where:

  • W = Overall gross weight on group of 2+ consecutive axles (nearest 500 lbs)
  • L = Distance in feet between extremes of axle group
  • N = Number of axles in the group

Exception:

2 consecutive sets of tandem axles may carry 34,000 lbs each if first and last axles are not less than 36 feet apart, and gross vehicle weight does not exceed 80,000 lbs including all enforcement tolerances.

Exceptions

WIDTH EXCEPTIONS:

  • • Unprocessed Logs, Pulpwood, Wood Bolts, Agricultural Products, Concrete Pipe: 108 inches (load only)
  • • Buses: 102 inches
  • • Implements of Husbandry: Any width for normal farming operations

LENGTH EXCEPTIONS:

Truck-Tractor + Semitrailer + Trailer (or 2 Semitrailers):

No overall length limit if each unit ≤28 ft 6 in OR combined length ≤58 ft (measured front of first to rear of second unit)

Truck + Trailer/Semitrailer:

Overall length ≤65 feet (designated highways only)

Logging Vehicles (saw logs, pulpwood, tree length poles):

Overall length ≤70 feet including load (designated highways only)

Auto/RV/Boat Transporters:

≤65 feet (stinger-steered ≤75 feet). Load may extend 3 ft front, 4 ft rear

Articulated Buses (Public Transit):

Maximum 65 feet

Special Vehicle Requirements

MOBILE HOMES:

  • • Body length: 45 feet
  • • With towing unit: 60 feet
  • • Width: 8 feet 4 inches
  • • Height: 12 feet 6 inches

FLAMMABLE LIQUID TRANSPORT (Flash point ≤70°F):

  • • Must meet Department of State Police safety standards
  • • Vehicles manufactured after July 27, 1978: 11 feet 8½ inches maximum height

Movement Restrictions

Counties with 600,000+ Population:

Truck/Truck-Tractor + Semitrailer (more than 9,000 gallons):

Movement allowed ONLY between midnight to 6:00 a.m. on designated routes

Truck-Tractor + Semitrailer + Trailer (or 2 Semitrailers):

Movement allowed ONLY between midnight to 6:00 a.m. on designated routes

Maximum Truck Speed

No truck, tractor or tractor with trailer, or any combination with gross weight (loaded or unloaded) exceeding 10,000 lbs shall exceed:

  • • The posted speed limit OR the speed limit on permit (whichever is less)
  • • 35 MPH where reduced loadings are enforced during seasonal weight restrictions

Special Permit Information

Vehicles or loads exceeding legal dimensions or weights require a SPECIAL TRANSPORT PERMIT for travel.

Permits issued only for:

Occasional movement of oversize or overweight vehicles/loads that cannot be dismantled, reduced, or rearranged to come within legal limits.

Application Methods:

  • • Michigan Permit and Routing System (MiPARs) computer program
  • • In person at MDOT Transportation Service Centers (TSCs)
  • • Through a permit service

⚠️ No overweight permits issued when weight restrictions are in effect

Need Help with Weight & Load Compliance?

Expert guidance on Michigan weight limits, dimensions, and special permits

Call (248) 478-8382 MI Truck Safety: (800) 682-4682

24175 Industrial Park Dr., Farmington Hills, MI 48335