BUILD America 250 Pilot Could Test 91,000-Pound Six-Axle Trucks

A proposed federal surface-transportation bill could create a voluntary pilot allowing participating states to test six-axle tractor-trailers at gross weights up to 91,000 pounds. TheTrucker.com outlined the provision August 28 as part of H.R. 8870, the BUILD America 250 Act. The House Transportation and Infrastructure Committee officially approved the broader bill 62-2 on May 22.

The standard federal Interstate weight limit is generally 80,000 pounds. Supporters argue that adding a sixth axle spreads weight across more contact points, allowing fewer trips for the same freight while controlling pavement and braking impacts. The source estimated that retrofitting a compatible trailer with another axle could cost roughly $3,000 to $10,000, though actual engineering, maintenance and tire costs would vary by equipment.

Opponents and undecided fleets are likely to focus on bridge loading, stopping performance, enforcement consistency and whether productivity gains offset equipment expense. A pilot would be designed to collect operating and safety information before Congress considered a broader change. It would not automatically authorize 91,000-pound combinations nationwide, and state participation would matter.

Most importantly, the committee vote did not make the proposal law. H.R. 8870 still must pass the full House, clear the Senate and receive presidential approval, and its language could change during that process. Carriers should not dispatch above current legal limits based on the proposal. Fleet planners can identify candidate routes, inspect bridge and state restrictions, price sixth-axle configurations and review cargo distribution without committing capital early. CDL drivers would remain responsible for legal axle weights, securement, inspections and safe operation; the pilot provision does not replace existing license, endorsement or hours-of-service requirements.