The GS-5 was a streamlined 4-8-4 Northern type steam locomotive that served the Southern Pacific Company from 1942 to 1958. Two locomotives were built by the Lima Locomotive Works and were numbered 4458 and 4459. GS stands for "Golden State" or "General Service." The GS-5s are identical in appearance to the GS-4s, the only difference being the roller bearings that gave the locomotive a smoother ride and added weight.