Big Boy - World's Largest Steam Locomotive

[steamlover22]

Kleman09 is right The Alleghenny is larger. It is the worlds most powerful, heaviest and tallest stean locomotive ever built. With about 7,500- 8,000 hp compaired to the big boys 6,800 hp, weight about 1.5 mill. lbs. compaired to the big boys 1.25 mill. lbs. and the height i don't know the facts. If anyone has the chance to go to The Henry Ford Museum in Dearborn, MI you could see 1 of only 2 Alleghenies left. One day i hope to donate money and get suport from the museum to get it running again.

[Kleman09]

The Alleghenny is larger. the boiler of the big boy could fit inside the alleghenny! Big boy has 6,800 horsepower, while the Alleghenny has 8,000 horsepower! No diesel has yet to reach 8,000.

[996TwinTurbo911]

@Kleman09 That is correct, I have seen both engines in person and while the 4000 is great the H-8 in real life looks so big that from viewing the engine from the side, slightly in front or back of the engine, makes it difficult to even see the large drive wheels because the boiler drastically overhangs from its shear size. I have gone back to view the H-8 at the Henry Ford about a dozen times because its enormous size !

[gartify]

Would love to grab a beer with that fella and just look over the whole train with him! Dudes a freak!

[Railroadnut844]

it is not the biggest steam loco, the actual largest was never determined, but some say it was the triplex 2-8-8-8-2, other like my self think the yellow stone is, and some think the Allegheny is the largest

[steamingpoopfart]

@Railroadnut844 Boiler length was 132 feet. It is indeed the largest.

[Railroadnut844]

@steamingpoopfart no, not necessarily the tender is often considered part of the engine, so some may say the Yellowstone is, or the triplex, or Alleganey with Vanderbilt tender. And you could say the one that weighs the most is largest.

[996TwinTurbo911]

@steamingpoopfart Not True, the entire length of the locomotive is 132' not the boiler. In the book "Lima's Finest" it provides actual blue prints that indicate the boiler from a 4000 class Big Boy will indeed fit within that of a H-8 Allegheny. I have had the privilege of seeing both of these engines in real life and although the H-8 is a few feet shorter in length, it still looks much larger for taller wider boiler and firebox that created more steam than the 4000. More steam equals more HP!

[IndianaPentecostal23]

Pistons have been cut :(

[Vorahk3985]

@IndianaPentecostal23 So it's #4018?

[IndianaPentecostal23]

@Vorahk3985 Yes! When the UP dieselized it was common for the crews to cut the pistons right at the wrist pins to avoid the pistons from jamming up during the tow to the dead line or scrap yard which could cause a derailment.