Union Pacific No. 838 (or simply UP 838) is an ALCO FEF-3 type of 4-8-4 steam locomotive owned by the Union Pacific Railroad.

Just like 844 This locomotive was used for passenger service on the Union Pacific railroad.

The UP ordered the last ten in 1944 (#835-#844), which were designated Class FEF-3. One of those ten was number 838.

UP 838 was retired from service in July 1962 after a few years of storage, and it was stored at the UP's Cheyenne roundhouse in Cheyenne, Wyoming in 1977.

As of today the engine is stored at the UP's Cheyenne, Wyoming roundhouse. The reason that #838 is put in storage at the Roundhouse is that it is kept as a source of spare parts for 844. No. 838's running gear and boiler are in much better condition due to 844's extensive use.