Michigan Oversize Load Regulations: The Complete Transport Guide
Important: We are not a permit service and we do not arrange permits for carriers. All information provided below is for informational purposes only. Always read permits and provisions carefully as we cannot guarantee the accuracy of information provided below.
Michigan DOT Ph#: 517-241-8999
For companies providing Heavy Equipment Transport or Machinery Hauling Services, understanding Michigan’s Oversize Permits and Heavy Load Compliance requirements is essential for successful Oversized Load Transportation. Here’s what you need to know about moving large equipment through the Great Lakes State.
Permit Details & Operating Hours
- Michigan Oversize Permits: Valid for 5 travel days and must be obtained before entering the state.
- Standard operating window: Sunrise to sunset.
- Weekend trial program: Saturday/Sunday until 3:00 PM for loads:
- ≤10′ wide
- ≤14′ high
- ≤90′ long
- Overweight-only loads: With legal dimensions and ≤70′ length may operate continuously.
Restricted Travel Areas & Times
- Urban county restrictions: For loads >12′ wide or >90′ long, during 7:00 AM – 9:00 AM and 3:00 PM – 6:00 PM in:
- Genesee, Ingham, Jackson, Kalamazoo, Kent, Muskegon, Macomb, Oakland, Saginaw, Westernau, Wayne counties.
- No travel: On major holidays and holiday weekends.
Critical Bridge Crossings
- Mackinac Bridge: Contact authority 24 hours prior (906-643-7600).
- Free escort provided for >legal weight or >10′ wide.
- No crossing when winds exceed 25 mph.
- Ambassador Bridge (Detroit-Windsor): $50+ fee for oversize loads.
- Restricted hours: 10:00 AM – 4:00 PM (weekdays).
- Phone: 313-496-1111.
Legal & Routine Permit Dimensions
Standard Legal Dimensions (No Permit Required)
- Length: 53′ semi-trailer (Interstate/designated highways; 41′ kingpin setting).
- Width: 8′-6″ (designated), 8′ (other roads).
- Height: 13′-6″.
- Weight Limits:
- Gross: 80,000 lbs.
- Steer axle: 700 lbs/inch of tire width (15,400 lbs max with 11″ tires).
- Tandem: 34,000 lbs (32,000 non-designated; 26,000 second tandem).
- Tridem: 42,000 lbs (39,000 non-designated).
- Single: 20,000 lbs (18,000 non-designated).
Routine Permit Limits
- Length: Up to 150′.
- Width: Up to 16′ (14′ during spring thaw).
- Height: Up to 15′ (shipper responsible for route clearance >13′-6″).
- Weight: Case-by-case basis (must register for permitted weight).
- Super Loads: Exceed routine limits; require 10-day processing with route surveys.
Escort Requirements
Standard Escorts
- Length Escorts:
- 90′: 1 escort.
- 100′: 2 escorts.
- Overhang: >15′ requires 1 escort.
- Width Escorts:
- 12′: 1 escort.
- 14′: 2 escorts.
- Height Escorts:
- 14′-5″: 1 escort with height pole.
- 15′: 2 escorts + approved route survey.
Special Requirements
- All axles (including lift axles) must be on the ground when loaded.
- Spring restrictions (Feb-Apr):
- No overweight permits issued.
- Axle weights reduced up to 35%.
- Tandem groups may be limited to 26,000 lbs.
- Frost line phone: 800-787-8960.
Safety & Compliance Requirements
Signage & Marking
- “Oversize Load” signs required front and rear.
- Flags required at all corners + widest points for overwidth/overlength.
Lighting
- Red light/lantern required for >4′ rear overhang at night.
Key Considerations for Transport Logistics
- Oversize Freight Solutions: Must incorporate buffer time for superload permits.
- Heavy Haul Project Management: Requires careful seasonal planning.
- Specialized Transport Services: Often needed for urban area moves.
- Logistics for Heavy Haul: Must consider:
- Bridge crossing protocols.
- Spring weight restrictions.
- Escort coordination.