RouteAllOversize Load Terms Every New Driver Should Know
Last verified September 8, 2026 against the federal and state rules linked in the Sources section.
Oversize load terminology splits into four groups: the dimensions, the permit types, the vehicles, and the paperwork. Learn the four dimension words first. Width, height, length and weight are the numbers every other term is built on.
On This Page
Every definition below comes from a federal or state rule, linked at the end.
Which dimension words matter most?
Four words carry every permit decision: width, height, length and weight. Width is the one that starts most permits, because the federal line sits low. Height and length limits are set state by state, and weight has its own federal number and its own formula on top.
Measure all four before you call anyone.
- Width — measured at the widest point of the load, not the trailer. Over 8 feet 6 inches (8'6") is oversize under federal rule.
- Height — measured from the road surface to the highest point. Many states set the line near 13 feet 6 inches (13'6").
- Length — measured overall, including any overhang. The federal rule protects a 48-foot semitrailer minimum.
- Weight — gross weight, single-axle weight and tandem-axle weight are three separate numbers, each with its own limit.
- Overhang — the part of the load extending past the trailer front or rear. It can trigger an escort on its own.
What does non-divisible mean?
Non-divisible means the load cannot legally be split into smaller loads. Federal rule 23 CFR 658.5 gives a three-part test. Splitting it would destroy its value, make it unusable for its purpose, or require more than eight work hours. States issue oversize permits only for non-divisible loads.
Three pallets of bricks are divisible.
One transformer is not, so only the transformer can be permitted.
A non-divisible load is one "which, if separated into smaller loads or vehicles, would" lose its value, its usability, or take over eight work hours to dismantle. — 23 CFR 658.5. Verified September 8, 2026.
The burden of proof sits with the applicant. If a state asks how long dismantling takes, you must be able to answer.
Which permit words appear on the paperwork?
Permit names describe how long the permit lasts and how much it covers. A single-trip permit covers one move on one route. An annual permit covers many moves for a year. An envelope permit sets maximum dimensions rather than a route, and a superload permit means the state must review your move first.
The names differ by state.
The structure underneath them does not change.
- Single-trip permit — one move, one route, one set of dates. Oklahoma charges $40 for oversize alone.
- Annual permit — repeat moves for a year within set limits. Virginia's extended-weight annual permit is $250.
- Envelope permit — maximum dimensions you may run repeatedly. Oklahoma's annual envelope permit is $4,000.
- Superload permit — a move so large the state engineers a route for it before issuing.
- Blanket permit — a state's own name for a recurring permit. Florida caps the annualized blanket fee at $500.
Which one fits your work is covered in Annual versus single-trip oversize permits. Superload triggers by state are in Superload permits: when your load is too big.
What are the vehicles and people called?
Three roles travel with an oversize move. The pilot car, also called an escort, drives ahead or behind and warns traffic. The height pole car is a pilot car carrying a pole that tests clearances. The permit service is the office that buys your permits for you.
Utah writes the escort's job into its rule in one sentence.
The escort driver's job is to "control and direct traffic to stop, slow, or proceed in any situations where it is deemed necessary to protect the motoring public." — Utah Admin. Code R909-2-24. Verified September 8, 2026.
- Pilot car — an escort vehicle. Utah requires a passenger vehicle or two-axle truck under 12,000 pounds.
- Height pole — a non-conductive pole set a few inches above the load to strike obstructions first.
- Certified escort — a pilot car driver holding a state certificate. New York, Georgia and Virginia each run programs.
- Permit service — a company that applies for permits on the carrier's behalf, for a fee on top of the state fee.
What the escort does hour by hour is in What a pilot car actually does.
Which weight words do I need?
Weight uses four terms. Gross weight is everything together, and axle weight is what one axle carries. The bridge formula limits weight by axle spacing. Federal rule 23 CFR 658.17 sets 80,000 pounds gross, 20,000 pounds on a single axle and 34,000 pounds on tandem axles.
The table gives the three federal Interstate numbers in one place.
| Term | Limit | Source |
|---|---|---|
| Gross vehicle weight | 80,000 pounds | 23 CFR 658.17(b) |
| Single axle | 20,000 pounds | 23 CFR 658.17(c) |
| Tandem axles | 34,000 pounds | 23 CFR 658.17(d) |
Two consecutive sets of tandem axles may each carry 34,000 pounds when the first and last axle are 36 feet apart or more. The gross total must not exceed 80,000 pounds even then.
- GVWR — gross vehicle weight rating, the manufacturer's maximum loaded weight for one vehicle.
- GCWR — gross combination weight rating, the same idea for the tractor and trailer together.
- Bridge formula — a calculation limiting weight by how far apart the axles sit.
Which route words appear on the permit?
Route words describe where you may drive. The permitted route is the list of highways printed on your permit. The National Network is the federal system where the 8 feet 6 inch width limit applies. A route survey is a physical check of a route before a large move is approved.
The National Network has a federal definition worth knowing.
- Permitted route — the exact highways your permit names. Leaving them voids the permit in most states.
- National Network — the highways each state opens to federally sized vehicles, defined in 23 CFR 658.5.
- Route survey — a check of bridges, wires and turns along a proposed route before approval.
- Curfew — hours you must not move. Many states also restrict movement to daylight.
Why a phone map cannot follow a permitted route is explained in Why Google Maps cannot follow your permit. RouteAll reads the permit you upload and drives the route it names, so the roads on the screen are the roads on the paper.
Use This Check In RouteAll
Try these terms against the fields in RouteAll’s permit review workflow. Compare the app’s extracted value with the original wording, especially where a dimension, direction or condition is abbreviated.
Before you roll
Learn non-divisible first, because it decides whether a permit is even available to you. Learn the four dimension words next, because every fee and every escort rule is priced from them. RouteAll does not issue permits or guarantee compliance. When a word on your permit is new, ask the issuing state rather than guessing.
Common questions
What does non-divisible mean on a permit?
Non-divisible means the load cannot be split into smaller legal loads. Federal rule 23 CFR 658.5 sets the test: separating it would destroy its value, make it unusable for its intended purpose, or take more than eight work hours. The applicant has to prove the eight hours.
What is the difference between oversize and overweight?
Oversize is about dimensions and overweight is about pounds. They are separate permits in many states and separate fees. Oklahoma charges $40 for oversize alone, $40 for overweight alone, and $80 when a load is both. Check which one your load triggers before you apply.
What does an envelope permit cover?
An envelope permit sets maximum dimensions you may run repeatedly for a period, rather than covering one trip. Oklahoma publishes an annual envelope permit at $4,000. Anything inside the envelope needs no new permit, and anything outside it does. Read the envelope's own dimensions carefully.
What is the bridge formula?
The bridge formula is a calculation that limits weight based on axle spacing. Federal rule 23 CFR 658.17 caps gross weight at 80,000 pounds on the Interstate System, and the formula can lower that figure further. Axles spread further apart may legally carry more weight.
Further reading
Sources
- United States, 23 CFR 658.5, definitions including non-divisible load and National Network. Read September 8, 2026.
- United States, 23 CFR 658.15, width limit of 102 inches. Read September 8, 2026.
- United States, 23 CFR 658.13, length limits including the 48-foot semitrailer. Read September 8, 2026.
- United States, 23 CFR 658.17, Interstate weight limits and the bridge formula. Read September 8, 2026.
- United States, 49 CFR 390.5, definitions of GVWR and GCWR. Read September 8, 2026.
- Utah, Utah Admin. Code R909-2-24, pilot escort vehicle duties and equipment. Read September 8, 2026.
- Oklahoma DOT, Permit Fees, addendum to OAC 730 Chapter 50. Read September 8, 2026.
- Virginia, Va. Code § 46.2-1128, annual permit fee of $250. Read September 8, 2026.
- Florida, Fla. Stat. § 316.550, blanket permit fee cap. Read September 8, 2026.
RouteAll reads the permit you provide. It does not issue permits or guarantee compliance. The driver remains responsible for the load. Rules change; verify against the permit and the issuing state before every move.