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Locomotive-Specs
ALCo UP 4-6-6-4 – photo 1© trainspo.com
Steam locomotive

ALCo UP 4-6-6-4

Built by ALCo

Top speed
110 km/h
68 mph
Track gauge
1,435 mm
Standard gauge
Years built
1936–1944
Axle arrangement
4-6-6-4

Overview of the ALCo UP 4-6-6-4

Discover the powerful UP 4-6-6-4 steam locomotive, an icon of the Union Pacific Railroad.

This distinctive locomotive, built by ALCo between 1936 and 1944, features the impressive 4-6-6-4 Whyte notation, showcasing its advanced articulated design for its era.

It boasts a top speed of 110 km/h and an exceptional tractive effort of 433 kN, making it a formidable machine capable of handling heavy loads with ease.

The UP 4-6-6-4 stands as a testament to railway engineering prowess, embodying both power and reliability that defined a significant period in transportation history.

A must-have for railway enthusiasts and collectors, this steam locomotive represents an era of mass transit and industrial development.

Experience the grandeur of the past with this magnificent steam engine, a crucial part of the Union Pacific's rich heritage.

ALCo UP 4-6-6-4 technical specifications

Value
Built byALCo · 1936–1944
Top speed110 km/h68 mph
Tractive effort433 kN97,342 lbf
Track gauge1,435 mmStandard gauge4 ft 8½ in
Whyte notation4-6-6-4

Operators of the ALCo UP 4-6-6-4

Railway companies that have operated the UP 4-6-6-4, with the class designation used by each of them.

OperatorClassCountry
Union Pacific RailroadUP ChallengerUnited States

ALCo UP 4-6-6-4 photos

Photos © their respective authors, shared on trainspo.com. They may show liveries or variants that differ from the specifications above.

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