Overweight Permits
Federal law caps standard gross weight at 80,000 lbs, with 20,000 lbs on a single axle and 34,000 lbs on a tandem axle group under the federal bridge formula (23 U.S.C. § 127) — anything above that requires a permit built around real axle math.
We verify gross and per-axle weight against each state's legal and permitted maximums, then submit overweight permit applications with the axle configuration each state's bridge formula requires.
No scale-house surprises, and no fines for axle weight that wasn't accounted for at the application stage.
- 01Confirm gross weight and axle-by-axle weight distribution.
- 02Check axle spacing against each state's bridge formula requirements.
- 03Submit overweight permit applications state by state along the route.
- 04Verify permitted weight covers the load as actually configured.
The bridge formula is the whole game
Federal law (23 U.S.C. § 127) caps standard gross weight on the Interstate System at 80,000 lbs, with 20,000 lbs on a single axle and 34,000 lbs on a tandem axle group — but the actual ceiling is set by the federal bridge formula (W = 500[LN/(N-1) + 12N + 36], enacted by Congress in 1975), which ties allowable weight to axle spacing and count. Two consecutive tandem axle sets can each carry the full 34,000 lbs if their outer axles are spaced 36 feet or more apart. An overweight permit that doesn't account for this correctly can result in a load that's approved on paper but still cited at the scale.
Why per-axle numbers matter as much as gross weight
A load can be within gross weight limits and still be overweight on a specific axle if it isn't distributed correctly — scale-house enforcement checks axle-by-axle, not just the total. Verifying the actual distribution before filing is what prevents a permit that looks right from failing in practice.