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Last Modified on Sep 04, 2026
Understanding the Michigan commercial truck weight and axle load limits is essential for staying compliant with state regulations and protecting road infrastructure. These regulations not only promote safety but also play a key role in minimizing wear and tear on public roadways.
Michigan’s Gross Vehicle Weight Limits
Michigan allows certain commercial trucks to weigh up to 164,000 pounds, provided they have enough properly spaced axles and comply with applicable axle-weight requirements. Michigan’s system differs from the federal 80,000-pound gross vehicle weight limit that generally applies on the Interstate Highway System. A Michigan truck does not automatically need a special permit simply because it exceeds 80,000 pounds.
Axle Load Limits in Michigan
Axle load limits have a vital role in Michigan’s truck weight regulations. The Michigan axle weight limits depend on axle spacing, gross vehicle weight, and the type of highway. Under Michigan’s normal loading rules in MCL 257.722, a truck weighing more than 80,000 pounds may generally carry up to 18,000 pounds on an axle spaced at least 9 feet from another axle.
The limit drops to 13,000 pounds per axle when spacing is between 3.5 and 9 feet. Axles spaced less than 3.5 feet apart are generally limited to 9,000 pounds each. Different limits apply to qualifying trucks weighing 80,000 pounds or less under the federal bridge formula. No wheel must exceed 700 pounds per inch of tire width. These Michigan truck weight limits aim to prevent excessive road damage caused by concentrated loads.
Federal Bridge Formula
Whether a truck is passing over the Mackinac Bridge, Ambassador Bridge, or Blue Water Bridge, the federal bridge formula determines how much weight certain trucks can carry. This figure is based on the number of axles and the distance between them. In Michigan, the formula generally applies to qualifying vehicles weighing 80,000 pounds or less on interstate and specially designated highways.
What Counts as a Commercial Vehicle in Michigan?
Under Michigan law, a commercial motor vehicle is generally one that is used in commerce, weighs 26,001 pounds or more, and is designed to carry 16 or more people, including the driver. Transporting hazardous materials requires a placard. Certain vehicle combinations with a gross combination weight of at least 26,001 pounds also qualify under state guidelines.
Seasonal Weight Restrictions in Michigan
Michigan reduces truck axle weight limits during the spring thaw to protect roads weakened by trapped moisture. Allowable axle weights are reduced by 25% on concrete pavements and 35% on all other road surfaces. All-season-designated routes are exempt from these reductions. Additionally, MDOT adjusts restrictions as needed throughout the spring.
Special Permits for Oversized Loads
Michigan requires transport permits for vehicles or loads that exceed the maximum legal size or weight limits. MDOT offers both single-trip permits for individual moves and extended permits that may be issued every year for qualifying vehicles and loads. Applications for these and other permits are submitted through the state’s permitting system. Failure to obtain a required permit can result in penalties for operating an overweight or oversized vehicle.
Penalties for Overweight Violations
When a truck is found to have exceeded the state’s limit, Michigan can impose fines based on how far the commercial vehicle exceeded its legal weight. Under MCL 257.724, certain improperly distributed loads can result in fines of $200 per axle or $400 per axle, depending on the amount of excess weight. Any vehicles in violation of these laws may be stopped from continuing until the weight complies with the Michigan weight restrictions.
Michigan’s Unique Approach to Trucking Regulations
Michigan takes a unique approach to regulating the weight of trucks. While other states measure weight per truck, Michigan allows weight to be measured by the axle. The heaviest legal weight that is allowed for a truck in the state is 164,000 pounds, but this is only permitted when used across properly spaced axles. Each axle should not carry more than 13,000 pounds.
Michigan is also known for “gravel trains,” multi-axle truck-and-trailer combinations used to haul gravel and other heavy materials. This arrangement allows the load to be distributed across more axles.
Why Michigan Truck Axle Configurations and Legal Weights Matter in a Crash Claim
Excessive or improperly distributed weight can affect a truck’s braking, handling, and stability.
In 2025, the state recorded 16,689 commercial motor vehicle-involved crashes, including 118 fatal crashes that resulted in 128 deaths. Evidence that a truck exceeded applicable weight limits could establish negligence.
Why You Should Hire a Commercial Truck Accident Lawyer
Being struck by a commercial truck can lead to immediate and long-lasting hardships. If you fail to hire a commercial truck accident lawyer, your ability to pursue compensation through a commercial truck accident claim could be compromised.
Michigan’s commercial truck accident laws strictly regulate the weight of trucks, and a Michigan commercial truck accident attorney can independently investigate the collision to determine whether the trucking company violated those laws.
FAQs
Q: What Is the Weight Limit on Commercial Truck Axles in Michigan?
A: Michigan’s commercial truck axle limits depend on axle spacing, vehicle weight, and roadway. Under the state’s normal loading rules, an axle spaced at least 9 feet from another axle may generally carry up to 18,000 pounds. The limit generally drops to 13,000 pounds per axle when spacing is between 3.5 and 9 feet and 9,000 pounds per axle when spacing is less than 3.5 feet.
Q: How Much Weight Can Go on Each Axle of a Semi-Truck?
A: The federal weight limit for semi-trucks is 20,000 pounds per single axle and 34,000 pounds for tandem axles. Michigan allows higher gross vehicle weights, but axle limits can differ based on vehicle weight, axle spacing, configuration, and roadway. These regulations are based on axle spacing and configuration to promote compliance with infrastructure guidelines.
Q: Can My Steer Axle Be Over 12,000 Pounds?
A: Yes. Michigan does not impose a universal 12,000-pound limit on steer axles. The allowable weight depends partly on tire width, with the Michigan axle weight chart generally limiting the load on any wheel to 700 pounds per inch of tire width. Other axle weight and vehicle requirements can also apply. While exceeding this weight is allowed, it’s essential to distribute the load correctly to avoid handling issues.
Q: What Is Considered a Commercial Vehicle in Michigan?
A: A commercial motor vehicle in Michigan is generally any vehicle that is used for commerce and has a gross weight of 26,001 pounds or more. Additionally, vehicles that can transport 16 or more people, including the driver, or hazardous materials are generally considered commercial vehicles. These large trucks are subject to both state and federal regulations.
Q: How Many Axles Can a Truck Have in Michigan?
A: Michigan allows a commercial truck combination to have up to 11 axles. A properly configured 11-axle combination can weigh as much as 164,000 pounds under Michigan’s weight laws. The allowable weight depends on axle spacing and individual axle loads, so having 11 axles does not automatically allow a truck to operate at the maximum gross weight
Q: Are Weight Limits Different in Spring or Winter?
A: Michigan law imposes reduced weight limits during the spring thaw, when moisture and changing temperatures can weaken roadbeds. On affected seasonal routes, allowable axle weights are reduced by 25% for rigid pavements and 35% for flexible pavements. All-season routes are generally exempt. MDOT adjusts when and where these restrictions apply based on changing road and weather conditions.
Contact Our Lawyer Team for Help With Truck Accident Cases
At Wigod & Falzon, our dedicated team understands the intricacies of Michigan’s laws. Contact us today.
