Safe and Efficient Transportation Act of 2011 - 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 (IHS) routes in the state if: (1) the vehicle is equipped with at least six axles, (2) the weight of any single axle does not exceed 20,000 pounds, (3) the weight of any tandem axle does not exceed 34,000 pounds, (4) the weight of any group of 3 or more axles does not exceed 51,000 pounds, and (5) the gross weight of the vehicle does not exceed 97,000 pounds.
Directs the Secretary of Transportation to establish a safe and efficient vehicle bridge infrastructure improvement program. Requires the Secretary to apportion amounts from the Safe and Efficient Vehicle Trust Fund to states for eligible bridge replacement or rehabilitation projects.
Amends the Internal Revenue Code to: (1) impose a tax on any vehicles that exceed federal weight limitations operating on the IHS, and (2) establish the Safe and Efficient Vehicle Trust Fund.