The Union Pacific Railroad (reporting mark UP) (or Union Pacific Railroad Company and simply Union Pacific) is a freight hauling railroad that operates 8,500 locomotives over 32,100 route-miles in 23 states west of Chicago and New Orleans. The Union Pacific Railroad system is the second largest in the United States after BNSF Railway and it is one of the world's largest transportation companies. The Union Pacific Railroad is the principal operating company of the Union Pacific Corporation; both are headquartered in Omaha, Nebraska.
The Union Pacific legacy began in 1862 with the original company, called the Union Pacific Rail Road, which was part of the First Transcontinental Railroad project, later known as the Overland Route. Two more Union Pacific railroads were formed after that, the Union Pacific Railway (the second company) which absorbed the original company in 1880 and the Union Pacific "Railroad" (the third company) which absorbed the Union Pacific Railway in 1897-1898.
The third incarnation of the Union Pacific Railroad which operated from 1897 to 1998 is referred to as Mark I and it makes up the bulk of the Union Pacific history. The third incarnation of the Union Pacific Railroad produced the well known Big Boy steam locomotives such as the Union Pacific 4014 and the Union Pacific 4012. Other well known steam locomotives were also produced by the third Union Pacific Railroad such as the Union Pacific 3985, the Union Pacific 3977, and the Union Pacific 844. The third incarnation of the Union Pacific Railroad also produced the Union Pacific 6936 diesel locomotive.
The current Union Pacific Railroad, the fourth incarnation, began in 1969 as the Southern Pacific Transportation Company (SP, SPTC or SPTCo), the last incarnation of the Southern Pacific railroad; the Southern Pacific Transportation Company became the fourth incarnation of the Union Pacific Railroad in 1998 with the Union Pacific-Southern Pacific merger which included SP's smaller railroads, the Denver and Rio Grande Western Railroad, the St. Louis Southwestern Railway and the SPCSL Corporation. The current incarnation of the Union Pacific Railroad inherits all operations of the third Union Pacific Railroad. The current incarnation of the Union Pacific Railroad is referred to as Mark II. All together, a total of four railroads used the "Union Pacific" name; however, all four railroads are commonly grouped as one railroad.
The parent company, Union Pacific Corporation was established in 1969, the same year the current railroad (Mark II) began. Besides the Southern Pacific, the Denver and Rio Grande Western, the St. Louis Southwestern and the SPCSL Corporation, the parent company, Union Pacific Corporation, acquired other western railroads over the years such as the Missouri Pacific Railroad, the Chicago and North Western Transportation Company, the Western Pacific Railroad and the Missouri–Kansas–Texas Railroad and all became part of the Union Pacific system, growing the Union Pacific system.
Union Pacific's main competitor is the BNSF Railway, the nation's second largest freight railroad, which also primarily services the Continental U.S. west of the Mississippi River. Together, the two railroads have a duopoly on all transcontinental freight rail lines in the U.S.
Freight Equipment
| Series | Class | AAR Type | Notes |
| Stock Cars | |||
| 41760-42759 | S-40-6 |
These cars were originally built by the American Car and Foundry Company and the 1000 cars were delivered to the Union Pacific Railroad during the spring and summer of 1918. They were all single deck cars numbered 45760-46759 and designated the S-40-6 class. In 1941, the railroad began a rebuilding program that converted 606 of these to double deck cars, and they were renumbered into the 41000 series with the final 3-numbers remaining the same. If the original number was 45798, the new number became 41798; or if the original number was 46304, it became 41304. Any car that was not converted to double deck retained its original car number, and both versions retained their S-40-6 Class designation. The cars went through another rebuilding program in the early 1950s that included extra bracing on the ends along with power hand brake and an AB brake system. Correct cars are available from the Union Pacific Historical Society. |
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| 45760-46759 | S-40-6 | These cars were originally built by the American Car and Foundry Company and the 1000 cars were delivered to the Union Pacific Railroad during the spring and summer of 1918. They were all single deck cars numbered 45760-46759 and designated the S-40-6 class. | |
Paint Schemes
Full timeline not yet established.
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Known to be in use in 1942-1947: "Road of the Streamliners" slogan on one side, "Serves all the West" slogan on other side. White lettering; slogan in yellow lettering. |
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Known to be in use in 1951 (O.W. R. & N.)-1953: "Be Specific - Ship Union Pacific" slogan replaces "Serves all the West" All lettering in yellow. |
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Known to be in use in 1954: Shield added. |
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Correct for 1954: ACF Type 27 Riveted 8,000 Gallon Tank Car Intermountain |
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| Known to be in use in 1966-1973: |  |
| Known to be in use in 1973: |  |
| Known to be in use in 1982: |  |