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US Transport Permit Pre-check

Reference

Screen load dimensions, gross weight, axle loads, and Bridge Formula weight before checking state permits.

Loaded combination

Federal law sets a 102-inch width on the National Network. There is no federal vehicle-height maximum; height and many length rules are set by the states and routes you use.

Axle data

Use scale weights, not estimates. A complete legal review checks every consecutive axle group; this pre-check evaluates the whole group and the maximum single and tandem values entered here.

Fill in the load and axle data, then press Check permits.

Ask the AI about this

Not sure what to check first? Hand the result to the assistant.

About this tool

This tool screens a loaded combination against the main US federal Interstate and National Network limits: overall width, gross weight, single and tandem axle loads, and Bridge Formula weight. It uses the machine, trailer, and cargo as one loaded combination.

Federal limits include 102 inches of width, 20,000 lb on a single axle, 34,000 lb on a tandem, and up to 80,000 lb gross. The Bridge Formula can require a lower weight based on axle count and spacing. A complete review must test every consecutive axle group; this pre-check tests the whole entered group plus the heaviest single and tandem values.

The federal government does not set a vehicle-height maximum or issue oversize/overweight permits. States and routes control height, many length rules, escorts, restrictions, and permits. Treat every result as a first screen and confirm the route with each state DOT before hauling.

Frequently asked questions

Does passing this check mean I do not need a permit?

No. It only screens the federal values entered. States issue permits and apply route-specific height, length, axle, bridge, escort, and local-road rules.

Why can a load under 80,000 lb still be overweight?

A single axle is generally limited to 20,000 lb and a tandem to 34,000 lb on the Interstate System. The Bridge Formula can also impose a lower limit when axle groups are close together.

What axle spacing should I enter?

Enter the distance between the centers of the first and last axles in the group being checked. This screen checks the whole combination; a legal review must repeat the formula for every consecutive axle group.

Why is there no federal height result?

Federal law does not set a maximum vehicle height. State limits commonly differ, and the approved route may have lower clearances, so height requires a state and route check.

What dimensions should I measure?

Use the overall loaded dimensions: widest and tallest points of the machine on the trailer, total combination length, and total height including the trailer deck.