. The GG1 is technically two 4-6-0 (G) locomotives under one shell, adding up to a 4.6k horsepower behemoth that was staggeringly powerful and fast even by today's standards. Thanks to the long life and usefulness of the GG1, many outlived the PRR, finding themselves in Penn Central, and later in their life, Amtrak paint. These locomotives were used in everything from freight service to pulling Amtrak passenger trains. Many of these locomotives continued to operate well into the 1980's their nearly 50 year lifespan a tribute to how powerful and effective this locomotive truly was.