Northrop Grummanand its Franco-German partner EADSare competing as a team. That alliance plans to offer a variant of EADS' Airbus A330 dubbed the KC-30.
Australia has ordered the Airbus tanker and Britain has picked EADS as the preferred bidder in its competition.
The 767 has been modified into a refueling tanker for Italy and Japan.
The Air Force said it would consider both the value and capabilities of the bids, and a higher-priced bidder could win if its overall approach outweighed the cost. The Airbus A330 sells on the commercial market for about $160 million. Boeing's 767-200 sells for about $120 million.
The Air Force hopes to select a winner later this year.
Several U.S. government agencies found that an Air Force tanker program begun in 2001 was riddled with problems. In 2004, Congress killed a proposal for the military to lease and buy 100 Boeing 767 tankers.