Union Pacific 6916

UP 6916 was built by the General Motors Electro-Motive Division in November 1969 as one of a series of 46 locomotives of the same type. It weighs 542,432 pounds and utilizes two Model 645E3A V-16 diesel engines, each rated at 3,300 horsepower, for a combined rating of 6,600 horsepower. Maximum speed was set at 80 miles per hour. By 22 June 1980, the 6916 was placed in storage due to a decrease in traffic. It was returned to service soon after,[1] but by 1983, most of the DDA40X types were stored out of service in Yermo, California. In 1984, a motive power crunch caused Union Pacific to reinstate 25 of the locomotives, including the 6916.[2] The locomotive was finally retired from service on 16 May 1985, and internally gutted as a parts source for SD40 and SD40-2 diesels.[1] The unit was donated "as is" to the Utah State Railroad Museum in 1986.[3]

The DDA40X locomotive type was nicknamed "Centennial" after the 100th anniversary of the driving of the Golden Spike in 1869, which signified the completion of the Transcontinental Railroad.[4] They are unique in that they are actually two power units on a single 98-foot frame, and are noted as being the largest diesel locomotives in the world. The 6916 is one of thirteen surviving Centennials.[5]

• UP 6916 was featured on the cover of the March 1985 issue of Pacific RailNews.
• The unit served as the prototype for an O-scale brass model released by Ajin and imported to the United States by Overland Models in 1999.[1]

• 
  UP 6900, showing the split between the two operating units
• 
  The cab of the 6916
• 
  Leslie type S3LR 3-chime air horn

• Union Pacific 6936 - another surviving DDA40X, and the sole operational unit.