In transportation terms, an oversize load is any load that exceeds standard or legal size and weight limits set by the Federal Highway Administration (FHWA). Different portions of roads and highways have different standards. Examples of overweight loads include construction machines (like cranes), prefabricated homes, mobile homes, houseboats, bridge beams, and industrial equipment.
According to the FHWA, any load over 80,000 lbs gross weight per vehicle, 20,000 lbs per single axle, or 34,000 lbs per tandem axle is above the federally mandated maximum weight limit set in section 23 CFR Part 658.17 of the National System of Interstate and Defense Highways.
Formula for calculating gross weight
One way to determine the gross weight of your load (which is not the same as its actual weight) is by using the following formula:
W = 500(LN/N-1 + 12N + 36)
Where W = overall gross weight, L = distance in feet between axles, and N = the number of axles.
The role of pilot cars
As overweight loads are transported to their destinations, pilot cars (also known as escort or flag cars) like the one above are used to safely escort the load and to warn other drives of the potential danger it poses. Pilot cars are also needed because often the load-bearing vehicle’s driver will not be able to safely see the road.
The lead pilot car typically follows a state trooper or local police vehicle, or a utility/bucket truck. A trailing pilot car may also be required to enforce a minimum safe distance for drivers behind the oversize load.
Pilot car drivers have the authority to stop the load for any reason, and to block traffic from passing the load.
Safely reaching the destination
If a permit has been obtained, a load has been checked against load weight limits, weather conditions are ideal, and pilot cars are ready to go, it should be a safe ride.
But some other things to consider include the route itself, as well as waypoints.
There are approximately 40,000 miles of U.S. highway permissible for oversize loads, so knowing which roads you can take is very important–and it’s just as important to make sure that you pass by weigh stations for weight compliance checks (and know where they are).
Applying for a permit
Of course, the most important part of safe heavy haul transportation over a long distance is to have the proper permit and training required to do so.
Because the FHWA does not award permits for oversize loads, but sets the safety standards, it requires that each state have its own permit guidelines. And, depending on the state, more than one permit may be needed.
In order to find out what permits you’ll need, contact the states in which you travel. Courtesy of the FHWA, the office numbers and websites are below:
District of Columbia 202-442-4670
Kansas Special Permits 785-368-6501
Louisiana 225-343-2345 or 800-654-1433
Maine 207-624-9000, extension 52134
Mississippi 888-737-0061 or 601-359-1717
New Hampshire 603-271-2691
New Jersey 609-530-6089
New Mexico 505-827-5540
New York 518-485-2999 or 888-783-1685
North Carolina 888-574-6683
North Dakota 701-328-2621
Oklahoma 877-425-2390 or 405-425-7012
Rhode Island 401-946-0090
South Carolina 877-349-7190
South Dakota 888-978-7249
Texas 800-299-1700, option 1
West Virginia 304-558-0384
British Columbia 800-559-9688
Manitoba 204-945-3961 or 877-812-0009
New Brunswick 888-762-8600
Northwest Territories 867-984-3341
Nova Scotia 902-424-5851
Ontario 416-246-7166, extension 6300 or 800-387-7736
Prince Edward Island (PDF, 1.25MB) 902-368-4291
Quebec 418-527-7775 or 800-567-7775
Saskatchewan 306-775-6969 or 800-667-7575
Yukon Territory 867-667-5644 or 800-661-0408, extension 5644