---
title: Michigan Oversize & Overweight Permits (OS/OW) | MDOT Superload | Alpine Truck Service
description: Expedited Michigan MDOT oversize permits, Detroit curfews, Mackinac Bridge clearances, and MSP escorts across I-94, I-75, and I-96. Call (918) 607-6547.
image: https://www.alpinetruckservice.com/alpine-third-party-charges.webp
---

# Michigan Oversize, Overweight & Superload Permitting Services

Comprehensive commercial trucking permits and heavy haul compliance across Michigan.

## Agency & Permitting Authority
- **Agency**: Michigan Department of Transportation (MDOT)
- **Portal**: MDOT MiTRIP Oversize/Overweight Permitting Portal
- **Regulatory Advisory**: State DOT regulations and permit processing queues are determined by individual state transportation authorities and vary by agency workload. Carriers should verify active route advisories and state requirements prior to movement.

## Legal vs. Routine Permitted Dimensions
- **Legal Width**: 8' 6" | **Max Routine**: 16' 0"
- **Legal Height**: 13' 6" | **Max Routine**: 15' 0"
- **Legal Length**: 53' Semi-Trailer / 65' Overall | **Max Routine**: 120' 0"
- **Legal Gross Weight**: 80,000 lbs (up to 164,000 lbs for multi-axle configurations meeting Michigan 11-axle spacing laws) | **Max Routine**: 164,000 lbs
- **Axle Limits**: Single: 20,000 lbs, Tandem: 34,000 lbs, Tridem: 42,000 lbs

## Permitting Scope & Services in Michigan
- **Routine Oversize (OS) Cab-Cards**: Single-trip authorizations for dimensions exceeding 8' 6" width or 13' 6" height.
- **Overweight (OW) Axle Permits**: Overload cab-cards for heavy machinery and configurations exceeding 80,000 lbs GVW.
- **Multi-Axle Superload Permits**: Specialized filings exceeding Over 164,000, including State DOT and certified partner bridge reviews, route surveys, and police escorts.
- **Annual & Blanket Fleet Permits**: Continuous-operation annual highway authorizations for construction fleets.
- **Temporary Trip & Fuel Permits**: 72-hour IRP vehicle registration and IFTA fuel tax credentials.
- **County, City & Toll Road Clearances**: Municipal authorizations and turnpike clearances.

## Superload Permitting & State Review Protocol
- **Weight Trigger**: Over 164,000 lbs GVW or exceeding individual Michigan axle group maximums
- **Width Trigger**: Over 16' 0" wide
- **Height Trigger**: Over 15' 0" high
- **Length Trigger**: Over 120' 0" overall length
- **State & Partner Bridge Review**: Michigan Department of Transportation (MDOT) electronic systems and certified structural engineering partners evaluate axle load distribution across bridge structures upon submission.
- **Route Surveys & Clearances**: Required for extreme heights/widths to verify overhead physical clearances.
- **Utility & Escorts**: Coordinated wire lifts with power utilities and State Police / Highway Patrol escorts.

## Pilot Cars & Escort Vehicle Requirements
- **Front Escort**: Required over 12' 0" wide on two-lane roads; over 14' 0" wide on multi-lane highways
- **Rear Escort**: Required over 14' 0" wide on multi-lane highways; length exceeding 90' 0"; rear overhang > 10' 0"
- **Height Pole**: Required for loads exceeding 14' 5" in height (lead vehicle with calibrated pole)
- **Police Escort**: Michigan State Police (MSP) escort required over 16' 0" wide, 16' 0" high, or over 164,000 lbs

## Metro Curfews & Travel Restrictions
- **Curfew Zones**:
  - Detroit Metro Area (Wayne, Oakland, Macomb Counties; I-75, I-94, I-96, I-696, M-10): 7:00–9:00 AM & 4:00–6:00 PM M-F
  - Grand Rapids Metro (I-196, US-131) during peak morning and afternoon commute hours
- **Travel Rules**: Daylight only (1/2 hour before sunrise to 1/2 hour after sunset) Monday through Friday. Saturday travel allowed until 12:00 noon for loads under 12' wide. No Sunday travel for oversize loads. Routine overweight-only loads may travel 24/7.

## Key Freight Corridors
- I-94 (Detroit to Chicago Freight Spine)
- I-75 (Mackinac Bridge to Ohio / Auto Corridor)
- I-96 (Detroit to Grand Rapids)
- I-69 (Port Huron International Gateway)
- US-131
- I-696

## Frequently Asked Questions
### How do Michigan's unique 11-axle heavy haul weight laws work?
Michigan law allows legal gross vehicle weights up to 164,000 lbs on multi-axle configurations (up to 11 axles) without special single-trip permits, provided individual axle limits (typically 13,000 lbs per axle) and spacings are strictly met.

### What are the permit rules for crossing the Mackinac Bridge on I-75?
Loads over 10' wide or exceeding standard axle limits require Mackinac Bridge Authority clearance. Movements during high winds (over 25-35 mph) are strictly held until conditions clear.

### What are Detroit rush hour curfew restrictions for oversize loads?
Oversize vehicles cannot travel in Wayne, Oakland, and Macomb counties between 7:00–9:00 AM and 4:00–6:00 PM on weekdays.

### How long does MDOT take to issue a Michigan oversize permit?
Routine single-trip permits submitted through MiTRIP are typically processed in 2–4 business hours. Superloads requiring bridge structural reviews take 3–5 business days.

## Contact & Direct Dispatch
- **Direct Phone**: (918) 607-6547 (CALL: [918-607-6547](tel:9186076547))
- **Email**: [permits@alpinetruck.com](mailto:permits@alpinetruck.com)
- **Online Intake**: [alpinetruckservice.com/permits/michigan](https://www.alpinetruckservice.com/permits/michigan)