Western Pacific 165, 0-6-0 locomotive in Portola, California.

(Xboxtravis7992, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons)



0-6-0 is the Whyte notation designation for steam locomotives with a wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles, and no trailing wheels. Historically, this was the most common wheel arrangement used on both tender and tank locomotives in versions with both inside and outside cylinders.

In the United Kingdom, the Whyte notation of wheel arrangement was also often used for the classification of electric and diesel-electric locomotives with side-rod coupled driving wheels. Under the UIC classification, popular in Europe, this wheel arrangement is written as C if the wheels are coupled with rods or gears, or Co if they are independently driven, the latter usually being electric and diesel-electric locomotives.


A diagram of the 0-6-0 Wheel Arrangement. Front of locomotive on left.

(Gwernol, Public domain, via Wikimedia Commons)



The 0-6-0 configuration was the most widely used wheel arrangement for both tender and tank steam locomotives. The type was also widely used for diesel switchers (shunters). Because they lack leading and trailing wheels, locomotives of this type have all their weight pressing down on their driving wheels and consequently have a high tractive effort and factor of adhesion, making them comparatively strong engines for their size, weight and fuel consumption. On the other hand, the lack of unpowered leading wheels have the result that 0-6-0 locomotives are less stable at speed. They are therefore mostly used on trains where high speed is unnecessary.

Since 0-6-0 tender engines can pull fairly heavy trains, albeit slowly, the type was commonly used to pull short and medium distance freight trains such as pickup goods trains along both main and branch lines. The tank engine versions were widely used as switching (shunting) locomotives since the smaller 0-4-0 types were not large enough to be versatile in this job. 0-8-0 and larger switching locomotives, on the other hand, were too big to be economical or even usable on lightly built railways such as dockyards and goods yards, precisely the sorts of places where switching locomotives were most needed.

The earliest 0-6-0 locomotives had outside cylinders, as these were simpler to construct and maintain. However, once designers began to overcome the problem of the breakage of the crank axles, inside cylinder versions were found to be more stable. Thereafter this pattern was widely adopted, particularly in the United Kingdom, although outside cylinder versions were also widely used.

Tank engine versions of the type began to be built in quantity in the mid-1850s and had become very common by the mid-1860s.


New York Central (Chicago Junction) 221, a USRA 0-6-0.

(1922 Locomotive Cyclopedia of American Practice, public domain, via Wikimedia Commons)


In the United States, huge numbers of 0-6-0 locomotives were produced, with the majority of them being used as switchers. The USRA 0-6-0 was the smallest of the USRA Standard classes designed and produced during the brief government control of the railroads through the USRA during the First World War. 255 of them were built and ended up in the hands of about two dozen United States railroads.

In addition, many of the railroads (and others) built numerous copies after the war. The Pennsylvania Railroad rostered over 1,200 0-6-0 types over the years, which were classed as class B on that system. The United States 0-6-0s were generally tender locomotives.

During the Second World War, no fewer than 514 USATC S100 Class 0-6-0 tank engines were built by the Davenport Locomotive Works, for use by the United States Army Transportation Corps in both Europe and North Africa. Some of these remained in service long after the war, having been purchased or otherwise adopted by the countries where they were used. These included Austria, Egypt, France, Iraq, the United Kingdom and Yugoslavia.

The fourteen SR USA Class engines purchased by the British Southern Railway in 1946 remained in service well into the 1960s. Designed to be extremely strong but easy to maintain, these engines had a very short wheelbase that allowed them to operate on dockyard railways.



Equivalent classifications

  • UIC class C
  • French class 030
  • Turkish class 33
  • Swiss class 3/3
  • Russian class 0-3-0

First known tank engine version
First use: 1850s
First known tender engine version
First use: 1827
Country: United Kingdom
Locomotive: Hackworth's Royal George
Railway: Stockton and Darlington Railway
Designer: Timothy Hackworth
Builder: Timothy Hackworth
Benefits: Total engine mass as adhesive weight
Drawbacks: Instability at speed