Wyoming Oversize Load Permits, Regulations & Axle Rules

Wyoming runs all oversize movements on a daylight rule, with daylight defined generously as one-half hour before sunrise until one-half hour after sunset. A load that exceeds legal size must stay within that window unless the Wyoming Highway Patrol (WHP) has granted specific nighttime permission. Several carve-outs exist for loads that don't push width into the oversize range: an overweight-but-legal-size load may move at any hour with a valid permit, and a load no wider than 10 feet may travel at night on the Interstate (with a limited 5-mile allowance onto primary/secondary roads to reach food, fuel, a truck stop, or the delivery point).

Two overlength exceptions also allow night movement without special WHP authorization: a single unit over 60 feet but no longer than 75 feet, and a single unit over 60 feet when running as part of a combination whose overall length stays under 110 feet, provided the vehicle is properly permitted, signed, and lighted. Emergency response to train derailments is a fifth exception, but only for the response leg, not the return trip.

Wyoming runs six holiday blackouts for escorted oversize moves: New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day, and Christmas. The suspension begins one-half hour after sunset on the eve of the holiday and ends one-half hour before sunrise the morning after. Three-day weekends stretch the window to the full three days, and a holiday that falls on a Saturday pushes the closure from sunset Thursday to sunrise Monday; a Sunday holiday runs from sunset Friday to sunrise Tuesday. Thanksgiving is a notable exception to the extended-weekend pattern: the closure covers Thanksgiving Day only, not the surrounding weekend. Overweight-only moves that are legal size are not subject to any of these holiday blackouts.

Wyoming does not publish city-specific rush-hour curfews for most permitted loads, but loads over 18 feet wide face a targeted restriction: they are prohibited on primary and secondary highways during school bus traffic hours or heavy commuter periods, as determined by the Overweight Loads Office (OWL). No statewide continuous 24-hour movement program exists.

Weather is an independent stop lever. No oversize or overweight movement is permitted when the highway has been restricted to "no unnecessary travel" or when the chain law is in effect. Wyoming classifies weather closures in tiers: Class 1 affects light oversize vehicles, Class 2 catches all escorted movements, Class 3 covers overwidth loads broadly, and Class 4 closes the road to all oversize. These weather restrictions do not apply to overweight-only loads.

Wyoming's commodity relief is concentrated in two lanes: agricultural and farming exemptions that are among the most operator-friendly in the country, and a dedicated Class E permit track for forest products and harvesting equipment.

Wyoming farmers and ranchers moving their own implements or produce of husbandry may exceed statutory width and height limits during daylight hours with no permit and no fee. Implements up to 16 feet wide don't need an escort as long as they stay right of the centerline. Once the implement exceeds 16 feet wide or the driver can't stay right of center, escorts are required. At 18 feet wide or 17 feet high, OWL approval is required. Implement dealers (businesses that maintain an inventory of ag equipment) share a similar exemption from width and height permit requirements; their overlength and overweight moves still need a permit.

Forest products hauled under a Class E permit may run up to 9'4" (112 inches) wide and 15 feet high, provided no single component of the load exceeds the standard 8'6" legal width. Baled hay, corn stalks, and combine headers under Class E are more generous: up to 12'6" (150 inches) wide and 15 feet high, again with no individual component exceeding 8'6". Neither class gets a length exemption. Forest products, sugar beets, gravel, livestock, and agricultural products that cannot be weighed at the point of loading may move on primary and secondary highways with a Class F overweight permit, up to 10 percent over legal axle weights and 5,000 pounds over legal gross under Gross Weight Table 1. Class F is not valid on the Interstate.

Building panels and trusses may be moved on a one-year permit up to 13'6" (162 inches) wide and 15 feet high. Recreational vehicles and motor homes that exceed 8'6" in body width can be permitted individually on a single-trip Class B or C permit; commercial operators moving multiple units may obtain a one-year commercial RV permit. Camp shacks, a Wyoming-specific category, may carry up to 2,000 pounds of personal-use items (mattresses, bedding, cookware, clothing, hygiene supplies) above their permitted weight, so long as everything is properly secured. Wyoming sets no special commodity routing or seasonal movement windows beyond the standard daylight and holiday rules.

Wyoming calls its heaviest permit tier a Super Load, processed under a Class A permit. A load becomes a Super Load the moment it exceeds any one of the Class B/C single-trip limits, and in Wyoming those limits are already high. The complete set of triggers: width over 18 feet, height over 17 feet, overall combination length over 120 feet, single axle weight over 25,000 lbs (or over 29,000 lbs when in a tandem group), tandem axle weight over 55,000 lbs, triple axle weight over 65,000 lbs, or gross weight over 160,000 lbs. Any one of those alone is enough.

Class A permits are approved exclusively by the Overweight Loads Office (OWL), a specialized unit within WHP. No Port of Entry, trooper, or other permit-issuing authority has approval power for Super Loads. OWL is open Monday through Friday, 7:30 AM to 4:30 PM, and is closed on weekends and holidays. Plan accordingly when calculating lead time.

Two thresholds inside the Super Load tier carry additional procedural weight. Loads over 18 feet wide or over 18 feet high require at least 24 hours' prior notice to OWL before the move; the permit cannot issue until that notice is given. For route studies, Wyoming warns that a thorough review "may require 72 or more hours to complete," meaning even a relatively uncomplicated Super Load application should be submitted several business days ahead, and complex ones should be planned weeks out.

The weight side of the Super Load tier stacks costs as loads grow heavier. Any load exceeding 80 tons (160,000 lbs) requires the state to analyze routing, structure, and highway capability before the permit issues, and the permittee must pay all state costs, including the expense of sending personnel to accompany the movement, before the permit is released. Loads exceeding 125 tons (250,000 lbs) face an additional layer of engineering and highway-capability analysis, and again the permit is withheld until all department costs are paid in full.

One additional constraint applies to the widest Super Loads: any load over 26 feet wide is not authorized to travel on roadways that are primarily 32 feet wide or less. OWL may grant exceptions for short distances, but this rule effectively locks the widest moves onto principal routes.

Wyoming does not use the term "route survey" as a formal permit document category, but the routing obligations for heavy and large Super Loads function the same way: WYDOT reviews the route before the permit issues, the carrier is responsible for verifying clearances along the way, and in the heaviest weight brackets the state must sign off on every structure before a wheel turns.

For Super Loads (Class A), OWL conducts a route study that may take 72 hours or more. For loads exceeding 80 tons, the state determines routing, structure, and highway capability to withstand the load before issuing the permit, and the carrier pays all associated state costs. For loads exceeding 125 tons, additional analysis of routing, structural adequacy, and highway capability is required, and again the permit does not issue until those costs are covered.

The carrier's own clearance responsibilities run parallel to OWL's review. The permit holder must verify that the vehicle or load dimensions can traverse the proposed route without damaging overhead wires or structures. If lifting overhead wires is necessary, the carrier must contact the responsible utility company and bear all costs, unless the wires are lower than regulations require. Local road access is a separate step: the permit holder must contact city and county officials to obtain approval before traveling on local government roads. Posted bridge and structure weight limits must be observed. Certain highways and structures are restricted below statutory limits, and any axle configuration not already listed in the Maximum Allowable Table requires OWL review and may be referred to WYDOT's Bridge Program for analysis.

The combined effect is that the carrier's routing obligation is broad: verify clearances, contact utilities, get local sign-off, and confirm the axle configuration is approved, all before the move. For Super Loads over 80 tons, WYDOT's state-level structural review is also a prerequisite to permit issuance, so the routing process must be completed and paid for before any permit is in hand.

Wyoming does not publish a dimensional threshold that mandates law-enforcement escort. The state's entire codified escort system uses civilian escort vehicles. All the published breakpoints for width, height, length, and overhang specify civilian escorts, not officers. The Wyoming Highway Patrol (WHP) plays an administrative role in the permit program rather than a frontline escort role: WHP operates the permit system through OWL, enforces permit conditions, and may halt or restrict movement, but is not assigned as a fixed-dimension police escort.

One specific situation does bring WHP into the escort picture: extreme emergencies requiring an escorted oversize or overweight move on a legal holiday or weekend. In those cases, the carrier must contact WHP directly; if WHP concurs the emergency is genuine, it will assist in obtaining the necessary permission and may accompany the move. This is a narrow exception, not a standard escort path.

For everything below the Super Load threshold, civilian pilot and escort vehicles handle all required escort duties. Escort vehicles must be single, licensed motor vehicles. Motorcycles and vehicle combinations are not allowed. Each escort must maintain approximately 1,000 feet from the oversize load unless a closer distance is needed to control the movement. All escort vehicles and the transport vehicle must be equipped with two-way radios capable of transmitting and receiving at all times; cellular or satellite phones do not meet this requirement. WHP retains general discretionary authority to require additional escorts based on load width, and permit-issuing authorities may require escorts for loads at or below the 17-foot height threshold on a case-by-case basis.