What was the first 2-8-4 steam locomotive?
2-8-8-4
The Northern Pacific Railway was the first railroad to order a 2-8-8-4. The first was built in 1928 by American Locomotive Company; at the time, it was the largest locomotive ever built. It had the largest firebox ever applied to a steam locomotive, some in area, to burn Rosebud coal, a cheap low-quality coal. But the firebed was too large for the available draft and the fire burned poorly. The problem was mitigated by blocking off the first few feet of the grates. Baldwin Locomotive Works built 11 more for the Northern Pacific in 1930. None were saved.
2-8-8-2
As of 2008, there are two surviving 2-8-8-2 locomotives, both former Norfolk & Western. N&W 2050 is from the railroad's Y3a class; Alco's Richmond works built it in 1923 and it is displayed at the Illinois Railway Museum in Union, Illinois. N&W 2156 is from the railroad's Y6a class; N&W's own Roanoke Shops built it in 1942 and it displayed at the Virginia Museum of Transportation in Roanoke, Virginia where it will be until 2020.