Wyoming OS/OD Overview
Permit Required
Yes – all oversize or overweight loads require a permit from the Wyoming Department of Transportation (WYDOT), Motor Vehicle Services.
Legal Limits (Without Permit)
- Width: 8'6"
- Height: 14'
- Length: 85' (combo); 53' trailer allowed
- Weight: 117,000 lbs GVW (with appropriate axle configurations)
Permitted Load Maximums (Typical Upper Limits)
- Width: Up to 18' with escorts
- Height: Over 16' requires route survey and utility coordination
- Length: Over 120' with routing and escort
- Weight: Over 250,000 lbs requires engineering analysis and bridge clearance
Superloads must be pre-approved and may require additional permitting time, police escorts, and route clearance from WYDOT districts.
Travel Hours
- Standard: ½ hour before sunrise to ½ hour after sunset
- Weekend: Travel allowed for loads under 10' wide, 14' high, and 110' long
- Holidays: No movement on major holidays or after noon the day before
- Night travel: May be allowed for smaller loads with proper lighting and permit endorsement
Escort Requirements (General Guidelines)
| Dimension | Escort Requirement |
|---|---|
| Width > 14' | 1 Escort (rear or front depending on route) |
| Width > 16' | 2 Escorts (front and rear) |
| Height > 16' | High pole escort and utility coordination required |
| Length > 120' | 1 or more Escorts depending on configuration |
Additional Notes
- All oversize loads must display “Oversize Load” signs, red/orange flags, and amber flashing lights
- Mountain passes and weather-related closures are common—check road conditions daily
- Permits are issued via the WYDOT Overweight & Oversize Permit System (WOTRS)
Detailed Information
PERMITS: Permits are obtained from Ports of Entry by the driver (see phone list at bottom of this page). Driver must call ahead to the Port/Scale at least one hour prior to arrival and obtain a clearance number. Failure to do this will result in up to a $500 fine and 24-hour shutdown. The permit is usually valid for one day or one trip.
OPERATING TIME: One-half hour before sunrise to one-half hour after sunset, including weekends, plus loads up to and including 10' wide, and all other dimensions are legal, may travel at night on Interstate highways only with proper lighting.
RESTRICTED TRAVEL: Holiday travel is usually allowed for loads not requiring escorts, but Ports of Entry are not open, so check with the Port on pre-ordering permit if you wish to run on the holiday.
LEGAL DIMENSIONS: Width: 8'6" Height: 14' Length: 60' semi-trailer and load (including any overhang) Weight: 80,000 – 117,000 Gross (Federal Bridge Formula applies) Single – 20,000 Tandem – 36,000 Tridem – 42,000 (8'1" to 8’5" of spacing); 36,000 with 8'; 42,500 pounds with greater than 8'6" spacing’s; and 43,500 with greater than 10' of spacing’s. Divisible Loads Exceeding 80,000: You can exceed 80,000 gross without a permit on state and Interstate highways as long as you are legal on all axle weights and bridge and you are licensed for at least the amount of your gross weight.
ROUTINE PERMIT LIMITS: Width: 18' Height: 17' Length: 110' Weight: Single – 25,000 Tandem – 55,000 Tridem – 65,000 Quad – 74,000 Register for up to 117,000 pounds to permit for that much or more. Loads in excess of these dimensions are considered as superloads and must go through the Central Office
ESCORTS: On Interstate Highways: Width: 15’ – 1 escort (Additional escorts may be required by the Highway Patrol for extreme widths.) On 2-Lane Highways: Width: Over 14’ or if load extends past center lane at any time – 2 escorts All Highways: Height: 17’6”- 1 escort with height pole Length: Over 110' – 2 escorts
SIGNS, FLAGS & LIGHTS: All oversize loads/vehicles must display Oversize Load on both front and rear. Flags are to be placed on projections extending beyond sides of trailer. Over 4' of rear overhang must be flagged (daytime) or lighted at night. Night running, if allowed, requires an amber clearance light on each front corner and red clearance light on each rear corner of the load and a revolving amber light, amber strobe, or two-way flashing amber lights at least 4" in diameter mounted on the vehicle visible to both front and rear.
SEASONAL LOAD RESTRICTIONS: No specific annual restrictions, but they may be imposed as necessary during spring thaw.