The transition from State Route 840 to Interstate 840 is taking place. Back in August, you'll recall we told you about a Federal Highway Administration ruling that would designate 840 an interstate. The biggest changes, some which Rutherford County drivers will notice, is signage. There are several signs that have already been replaced along I-840. T-DOT says the change was requested to encourage more economic growth along the corridor and more traffic diversion around Middle Tennessee's congested urban core. The change, which cost T-DOT 230-thousand dollars for new signage, is expected to be completed by the end of the year.