Safe, Flexible, and Efficient Trucking Act of 2015

This bill allows a state to authorize a vehicle with a maximum gross weight (including enforcement tolerances) exceeding certain federal weight limitations to operate on Interstate Highway System routes in the state if:

• the vehicle is equipped with at least six axles,
• the weight of any single axle does not exceed 20,000 pounds,
• the weight of any tandem axle does not exceed 34,000 pounds,
• the weight of any group of 3 or more axles does not exceed 51,000 pounds,
• the gross weight of the vehicle does not exceed 91,000 pounds, and
• the vehicle complies with a specified bridge formula.

The Department of Transportation may issue regulations necessary to require such a vehicle to include one item of additional equipment not otherwise required by law, but only if the equipment item is available at the time the rule is proposed.