Alabama Truck Weight Limits and Permit Sources

At-a-glance summary

Field-level reference data

The weight fields on this page each come with a source, a status, and a confidence label — that combination is what lets a dispatcher use this reference honestly. The gross, single-axle, and tandem rows draw from the federal Interstate framework and the FHWA state law compilation, which is the starting point for most FHWA-baseline states. Alabama state-specific detail lives in the FHWA compilation linked in the table; check that source for any non-Interstate route that departs from the federal numbers.

Reading the Alabama weight table

Start with the gross row, but read the axle-group rows before treating the load as settled. A load that clears 80,000 lb gross can still be over on drive tandems, trailer tandems, or the bridge calculation — those checks run independently. For Interstate routes, the federal baseline applies. For Alabama state highways and local roads, verify the FHWA state law compilation and any local postings before assuming the Interstate numbers extend to the whole trip.

Bridge formula context matters when axle spacing is close to a limit. The Alabama page uses FHWA bridge formula sources for that calculation; the actual route and axle configuration control the result. If the margin is tight, note which row drove the review and which source was checked — that information is much more useful than a generic “checked weight” note later.

Permit and route authority in Alabama

ALDOT Oversize/Overweight Permits is the confirmed permit authority for Alabama over-legal moves. Any load that exceeds Alabama’s weight or size thresholds needs a permit from ALDOT before the truck moves — not during or after. The permit covers route, dates, vehicle configuration, axle weights, and may include escort requirements or time-of-day restrictions. Match the issued permit to the actual route and configuration before releasing the load.

If equipment, route, or travel dates change after the permit is obtained, treat it as a new review. ALDOT permit terms don’t automatically transfer to a different trailer or an alternate route.

Seasonal, route, and local checks

No statewide frost-law or seasonal weight restriction page was confirmed for Alabama during this review. That absence doesn’t mean seasonal or local restrictions can’t apply to specific roads or bridges — it means no single official Alabama source was found that resolves every route situation. Posted bridge limits, construction zones, and permit conditions can still impose movement restrictions regardless of season.

For routes that include county roads or local streets, check those sources separately from the state permit.

Tickets and enforcement notes

The Alabama Law Enforcement Agency Motor Carrier Safety Unit is the enforcement agency confirmed in this review. If a weight violation results in a citation, the Alabama judicial traffic schedule materials — specifically the Rule 20 traffic schedule — give context for how overweight, overheight, and overlength truck citations are handled. The actual citation and court instructions control the outcome; the judicial schedule is background, not a substitute for the citation record.

A private scale ticket is a weight measurement. It doesn’t alter a citation that was already issued or establish permit authority. Keep the scale ticket with the dispatch record, but treat the citation document and the official source separately.

Source-strength notes for Alabama

This page has 3 high-confidence, 23 medium-confidence, and 3 low-confidence fields across 7 source records. High-confidence fields have direct official support — the agency language matches the field value without interpretation. Medium-confidence fields are supported by official material but involve some inference, often because the source uses general permit language rather than stating the field value directly. Low-confidence fields mark the gaps: seasonal restriction and the official seasonal URL are the two low-confidence areas here.

Use the confidence label to decide whether a field needs a live agency check before dispatch. A medium-confidence permit note is usable as a starting point. A low-confidence seasonal field should prompt a direct check of the route and current conditions.

Building an Alabama source file

A practical Alabama dispatch file should include the current scale ticket, the ALDOT permit confirmation, the route approved under that permit, and a note on any field that was confirmed live. The axle weight table, permit office list, seasonal status notes, and fine-source comparison pages complement this state page for multi-state planning.

For ticket reading, use How to Read a CAT Scale Ticket. Distribution adjustments belong with How to Slide Tandems. Bridge spacing questions belong with Bridge Formula Explained.