The SD80MAC is a 5,000 horsepower (3.7 MW) C-C diesel-electric locomotive. The model uses a 20-cylinder version ofEMD's 710G prime mover, and is the first diesel locomotive to use a 20-cylinder engine since EMD's SD45 and SD45-2. It introduced a wide radiator housing similar to GE Transportation locomotives and the placement of dynamic brakes at the rear of the locomotive, which is a quieter location, features that were incorporated into the SD90MAC and SD70ACe models. Key spotting difference between the SD80MAC and SD90MAC include no external rear sandbox on SD90MAC, rear number boards, and the placement of the front numberboards (above the cab windows on SD80MAC, on the nose on most SD90MACs). It also has recessed red marker lights in the nose, an identifying feature unique to Conrail locomotives, althoughNorfolk Southern (NS) has removed the lights on most of their engines.
All 30 units built were delivered to Conrail, and 28 production units were completed, tested, and painted at the formerPennsylvania Railroad shops in Altoona, Pennsylvania. The other two units rostered by Conrail were EMD demonstrator units that were purchased outright Many consider the SD80MAC to be the last new locomotive Conrail purchased as a truly independent railroad. In the split of Conrail, Norfolk Southern received 17 units (numbered 7200–7216) while CSX got 13 (800–812, being renumbered to 4590–4602). The former Conrail units were the first AC traction locomotives owned by Norfolk Southern, with the railroad not ordering more until late 2008 with an order of General Electric's ES44AC.