Union Pacific No. 4023 is a Articulated 4-8-8-4 Big Boy type steam locomotive built by the American Locomotive Company (ALCO) in 1944 as part of the Union Pacific Railroad. Toward the end of steam operations, in 1956, No. 4023—along with Challenger No. 3985—received a general overhaul to extend its service life by a few more years. After their final runs in 1959 and 1957 respectively, both locomotives were stored indoors at the Union Pacific roundhouse in Cheyenne, Wyoming by 1962.
A rare photo from Ron Ziel’s Twilight of Steam Locomotives shows both 3985 and 4023 in freshly overhauled condition inside the Cheyenne roundhouse. Though the locomotives were officially retired, they remained protected indoors until sometime between 1971 and 1974. Afterward, 4-6-6-4 Challenger No. 3985 was moved to outdoor display near the Cheyenne depot, while No. 4023 was relocated to the grounds outside the Union Pacific shops in Omaha, Nebraska.
When the UP shops in Omaha were shut down in the late 1980s, 4023 was moved to Kenefick Park, where it was displayed alongside Union Pacific Centennial EMD DDA40X No. 6900. The locomotive remained there for many years, though exposure to weather began to take a visible toll on its exterior condition.
In the early 2000s, as the city of Omaha prepared to redevelop its riverfront area—including the former UP shop sites and Kenefick Park—plans originally included relocating 4023 and the DDA40X to a new display near a planned convention center. However, a change in the development plans later excluded the locomotives from the final design.
As a result, both locomotives were temporarily housed at the Durham Western Heritage Museum in downtown Omaha. In March 2005, 4023 was moved again—this time to its current home near Lauritzen Gardens. There, the locomotive received cosmetic restoration including a fresh paint job and replacement of missing parts such as the headlight. There are also cosmetic dummy replacement parts for the whistle, safety valves, boiler jacket, and lubricator cranks.
Today, 4023 still stands on display in Kenefick Park as the largest surviving steam locomotive in the second batch, preserved as a symbol of the final era of American steam power. It is one of eight surviving UP Big Boys currently in preservation, and it is one of seven on display. An eighth, 4014, was restored to operating condition in May 2019.
Trivia[]
- No. 4023's and No. 6900's move to Kenefick Park in 2005 was featured in an episode of "Huge Moves".[1]
- It is the only surviving member that was built in the second batch of Big Boys that were constructed in 1944 while the other seven survivors all came from the first batch in 1941.
- The engine can be seen side by side with fellow surviving Big Boy #4004 in Herron Rail Video's Articulateds America's Biggest Steam DVD.
- While on display in Kenefick Park, 4023 began to deteriorate in condition, requiring a new paint job in 2025.[2]
Gallery[]
