New info has come to light in the hunt for the Tom Brady Super Bowl jersey ... and could all come down to the search of an 18-wheeler that was packed up right after the game.

TMZ Sports spoke with law enforcement sources involved in the search who tell us they are "hopeful" the jersey was put on a team equipment truck destined for Boston.

We're told the truck was never thoroughly searched before it left NRG Stadium in Houston -- and contains all sorts of team and player equipment.