Wyoming Commercial Vehicle Permits and Legal Limits

Operating oversize or overweight loads in Wyoming requires strict adherence to Wyoming Department of Transportation (WYDOT) regulations. Under Wyoming Statute 31-18-802, vehicles exceeding legal dimensions or weights must secure a permit before entering the state or moving on public highways. The state is unique for its high-altitude mountain passes and wind conditions, which frequently trigger road closures on I-80 and I-25 for high-profile vehicles. Carriers must monitor WYDOT District reports to ensure safe passage through these corridors, as wind gusts often exceed 60 miles per hour. DispatchTool helps carriers manage these complexities by integrating truck-safe routing that accounts for Wyoming's specific bridge heights and seasonal weight restrictions. Dispatchers can use the platform to store permit documents and track permit expiration dates across a fleet, ensuring drivers have digital access to required paperwork at ports of entry. To start streamlining your Wyoming permit management and routing, create a DispatchTool account.

Legal Dimensions and Weight Limits

In Wyoming, a vehicle is considered oversize if it exceeds 8 feet 6 inches in width, 14 feet in height, or a total length of 60 feet for a single unit and 81 feet for a semi-trailer. The legal gross vehicle weight (GVW) is capped at 80,000 pounds on the Interstate system, following the Federal Bridge Formula B. However, on secondary roads, Wyoming allows up to 117,000 pounds for specific configurations with a permit. Axle weight limits are set at 20,000 pounds for a single axle and 34,000 pounds for a tandem axle. Any vehicle exceeding these thresholds must apply for a Class A, B, C, or D permit through the WYDOT Overweight/Oversize Permit System.

Permit Types and Associated Fees

WYDOT offers several permit categories based on the frequency and size of the load. A Single Trip Permit is valid for a one-way movement over a period of 96 hours, with fees starting at $25 for oversize only and $0.06 per ton-mile for overweight loads. For carriers operating regularly, a Class C Multi-Trip permit allows for multiple movements of specific items for up to 90 days. The state also issues Superload permits for vehicles exceeding 160,000 pounds or 18 feet in width, which require a detailed route survey and at least 24 to 48 hours for engineering review. Carriers should also account for the $0.06 per ton-mile fee, which applies to any weight exceeding the legal limit for that specific axle configuration.

Escort Vehicle Requirements

Escort vehicles, also known as pilot cars, are mandatory for loads exceeding specific dimensions to ensure public safety. For movements on two-lane highways, one escort is required if the width exceeds 12 feet, and two escorts are required if the width exceeds 14 feet. On Interstates, an escort is typically only required if the width exceeds 15 feet. If a load is over 17 feet wide or 17 feet high, WYDOT may mandate a Highway Patrol escort. All pilot cars must be equipped with two-way radios, 'Oversize Load' signs, and amber flashing lights that are visible from 500 feet. The cost for third-party pilot cars in the region typically ranges from $1.75 to $2.25 per mile, depending on the route's complexity.

Daylight and Holiday Restrictions

Wyoming generally permits the movement of oversize loads from one-half hour before sunrise to one-half hour after sunset. Movements are prohibited on major holidays, including New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving, and Christmas. If a load is only 'over-length' and does not exceed 10 feet in width, night towing may be permitted with specific lighting requirements. During the winter months, typically from October through April, permits are subject to immediate suspension if hazardous weather conditions or 'Level 1' chain laws are in effect. WYDOT Rule Chapter 5 specifies that movements are halted if visibility is less than 500 feet or if roads are covered in black ice.

Bridge and Clearance Limitations

Wyoming's mountainous terrain results in numerous bridges with vertical clearances lower than the standard 14 feet 6 inches. The WYDOT Bridge Program maintains a database of restricted structures, particularly on the I-80 corridor through the Laramie Mountains. Loads exceeding 14 feet 6 inches must be routed through specific interchanges or use the frontage roads if clearance is insufficient. Bridge weight formulas are strictly enforced; for example, a vehicle with a 9-axle setup may be allowed a higher GVW than a 5-axle setup for the same span. Carriers must provide exact axle spacings to within one inch when applying for overweight permits to allow for accurate structural stress calculations by state engineers.

Port of Entry Procedures

All commercial vehicles entering Wyoming must stop at the first available Port of Entry (POE) unless they are equipped with a PrePass or similar electronic bypass system that is currently green-lit. There are 14 permanent POE locations across the state, including major stations at Cheyenne, Evanston, and Sheridan. At the POE, officials will verify the permit, check for proper securement, and ensure the driver is compliant with the Electronic Logging Device (ELD) mandate. Failure to stop at a POE is a violation of Statute 31-18-301 and can result in fines exceeding $200 plus court costs, along with an immediate safety inspection that may delay the load for several hours.

Sources

Wyoming Department of Transportation (WYDOT) (2024) — https://www.dot.state.wy.us/home/trucking_commercial_vehicles/oversize_overweight_permits.html Wyoming State Legislature - Statute 31-18-802 (2023) — https://wyoleg.gov/statutes/compress/title31.pdf ATRI - Wyoming State Summary (2024) — https://truckingresearch.org/

Frequently asked

What is the maximum width allowed without a permit in Wyoming?

The maximum width allowed without an oversize permit is 8 feet 6 inches. Anything exceeding this dimension requires a permit from WYDOT.

How much does a Wyoming overweight permit cost?

The base fee for an overweight permit is $25, plus a weight fee calculated at $0.06 per ton-mile for any weight exceeding the legal limit.

Are oversize loads allowed to run at night in Wyoming?

Generally, no. Movement is limited to daylight hours (30 minutes before sunrise to 30 minutes after sunset). Only loads that are exclusively over-length up to 10 feet wide may be granted night travel exceptions with proper lighting.

When does Wyoming require a pilot car for wide loads?

On two-lane roads, a pilot car is required if the load exceeds 12 feet in width. On four-lane divided highways or Interstates, a pilot car is required once the width exceeds 15 feet.

What is the height limit before needing a permit in Wyoming?

A permit is required for any vehicle and load that exceeds a total height of 14 feet.