The Pennsylvania Railroad Q-2 4-4-6-4 was more successful than the one-off Q-1, and the railroad's Juniata Shops outshopped 26 examples in 1945-46. However, this duplex design had serious maintenance issues which, so late in the steam era, never had a chance to be corrected with a redesign. Tests showed the Q-2 capable of up to 8000 horsepower, but it used water at a prodigious rate which limited the time it could run before stopping at a water column. Unlike the high-drivered Q-1, the Q-2 reverted to 69-inch drivers, the general maximum for locomotives restricted to freight service. Additionally, both the front and rear engines faced in the "normal" direction; the 19¾x28 front cylinder set drove the first four drivers, the 23¾x29 rear cylinders the remaining six drivers. For other specifications see the commentary for No. 6180 following. This image, attributed to Charles E. Winters, was taken in Chicago on December 1, 1948.