Dieselisation

In terms of road transport, diesel gained popularity first with commercial hauliers, throughout the later 20th century, and then with passenger car users, particularly from the 1970s onwards, once diesel engines became more refined and also more readily available in passenger cars. Diesel had by this point long been a popular choice for taxi operators and agricultural users.

In Europe as a whole, Peugeot and Mercedes-Benz in particular developed reputations for passenger-car diesel engines, whilst VM Motori developed some significant motors for four-wheel drive vehicles.

In London the famed "Hackney Carriage" taxi has long since been powered by a diesel engine. The high reliability, ease of driveability and excellent fuel efficiency of such an engine allows the taxis to carry many people for a lower cost than might otherwise be incurred through the use of conventional petrol engines.

Lightweight diesel engines suited for road vehicles were introduced in the late 1930s. They were soon used in bus coaches, heavy trucks, tractors, and construction equipment. The postwar era saw rapid replacement of gasoline with diesel for heavy trucks and buses, with engines provided mostly by Cummins and Detroit Diesel, and some by Buda Engine Co. (later a division of Allis-Chalmers). Rising gasoline prices during the 1970s spurred interest in diesel for passenger cars, although it soon faded in popularity for private vehicles other than pickup trucks.

Weighing against the cost of, and inertia against, replacing the large investment that railroads had in existing steam power were the dramatic increases in flexibility and efficiency with diesel. Diesels could and did have a significantly higher initial price per unit-horsepower delivered; however, their operating and support costs were much lower and unit availability between inspection repair and maintenance stops were much higher. Infrastructure to support diesels underway is much simpler and less costly, owing to their far greater range between fueling stops and absence of water stops. Also, diesels use much less fuel and no manpower when idling, something locomotives often do. Diesels can be parked running for days unattended, whereas steam engines must be constantly tended to if not completely shut down. Bringing a steam engine boiler up to operating temperature is often regarded as both an art and science, requiring much training and experience. A diesel is much simpler to start and shut down. Diesels simply required significantly less time and labor to operate and maintain.

Diesels also had advantages in service flexibility. They are more scalable to power requirements, owing to the control systems that allowed multiple units to be controlled by one operator. "Double header" steam power required a crew for each locomotive. The range of efficient operation for diesels under different speeds and grades is much greater than with steam locomotives, which tended to be purpose-built for specific situations. A high speed Hudson steam locomotive is good for only one situation, high speeds on level grades.

Initially, diesel locomotives were less powerful than the typical steam locomotives. Between the late 1930s and the late 1950s the power available with diesel locomotive engines roughly doubled, although the most powerful steam locomotives ever built still exceeded the power of the most powerful diesel locomotives from the late Twentieth Century.

Dieselization could be accomplished without any major changes to rail infrastructure, presenting lower initial capital costs than electrification. However, in situations where volume is sufficient to amortize the capital costs of electrification, the greater efficiency and speed available with electrification are significant advantages and electrified systems are favored throughout most of the developed world, with the most salient exceptions being North America, the British Isles, and Australia.

Relatively short trackage between destinations and high traffic volumes in Europe favoured electrification to replace steam. Most lines are electrified, with the major exception of the United Kingdom, Ireland and Albania. Some low volume secondary lines and switching service also remain unelectrified. Most countries used diesels as an interim solution during postwar reconstruction and electrification. Some countries, most notably Switzerland, have electrified their whole network. The most powerful electric locomotives in western Europe pull Swedish ore trains.

In Britain the Great Western Railway introduced diesel railcars in the 1930s and the first British mainline diesel locomotive was built by the London, Midland and Scottish Railway in 1947 but, unlike elsewhere in the developed world, the transition away from steam was delayed during the early postwar years. The delay was driven by two economic considerations: the lower initial cost of steam locomotives for immediate replacement of the large number of locomotives worn out from wartime service, and a projected rise in the cost of petroleum relative to coal, a plentiful domestic resource. Nationalisation of the railways took place in 1948; diesel locomotives were first introduced on a wide scale following the Modernisation Plan of 1955. Poor reliability among the first diesel locomotives used in the Modernisation Plan caused it to be implemented at a slower pace while the problems with the locomotives were worked out during the second half of the 1950s.[3]

The last steam locomotive for British Railways was built in 1960 and named "Evening Star" (number 92220). Steam traction was withdrawn on British Railways in 1968 and largely replaced with diesel traction (with electrification on a minority of lines). Steam was finally eliminated on Northern Ireland Railways in 1970 and entirely replaced with diesel.

Steam continued on the London Underground until 1971, as London Transport considered steam to be cheaper than diesel shunters. After 1971, diesel hydraulics and battery electrics took over shunting duties on the LU. Steam continued on many industrial railways in the UK mainly with the National Coal Board And British Steel Corporation until the 1980s.

Ireland also chose dieselization over electrification and as of 2015, the railways in Ireland (with the exception of the electrified Dublin Area Rapid Transit) remain entirely diesel operated.

The small initial market for diesels was created by the State of New York's Kaufman Act of 1923, which prohibited operating steam locomotives in New York City and adjacent towns. Mainline passenger railroads had already been electrified, or their electrification had been planned regardless of the Kaufman Act. Electrification of numerous freight yards was uneconomical, and railroads turned to diesels. The first ALCO boxcab switcher was put in operation in 1925 by Central Railroad of New Jersey at its 138th Street[4] waterfront terminal in The Bronx.[5] The second was delivered in the same year to Baltimore and Ohio Railroad's yards on Manhattan. Both worked into the late 1950s and survive in museums to date.[6] The advantages of diesel-electric switch engines gained them a widespread market during the 1930s.

Dieselization got a boost in the early 1930s from three factors: the development by General Motors and its Winton Engine Corporation subsidiary of diesel engines with vastly improved power-to-weight ratios and output flexibility; the desire of railways to find more cost-efficient locomotion for passenger service at the height of the Great Depression; and design innovations in rail equipment that reduced weight, making the contemporary diesel engines, which were low-powered by today's standards, viable for mainline passenger service. The mid-1930s saw the introduction of lightweight diesel-powered streamlined trainsets such as the Burlington Route's Zephyrs and Union Pacific's M-1000x "City" trains, which were diesel's first assault against the dominance of steam in mainline passenger service. During the second half of the decade, diesel locomotives with sufficient power for full-size passenger trains were developed and put into regular production. Improved GM diesel engines in 1938 increased power and reliability. Dieselization of passenger service gained momentum as the decade drew to a close and the first model of mainline diesel freight locomotive was on the market in 1940. Dieselization was especially attractive to western railroads, for whom the watering requirements of steam locomotives were a problem in vast stretches of the western interior. Coal-country railroads were generally reluctant to embrace diesel, a competitor to one of their main hauling markets, well into the 1940s.

Competition from diesel spurred a round of development in steam locomotive technology. High style, high speed "streamliners" produced during the second half of the 1930s became the speed kings of passenger service. Duplex and articulated steam locomotives built in the early 1940s exceeded the power of any diesel ever built, although their power was edged by gas turbine-electric locomotives during the 1950s. But the limits of steam technology were rapidly being reached. The new locomotives were mechanically complex and extremely specialized. Locomotive size became an issue, as steam engines became so big in the 1940s that the cylinder and boiler dimensions were pushing the limits that the loading gauge would allow. Fireboxes became so big that firing a steam locomotive became an extremely difficult job without the aid of mechanical stokers. Mechanical stokers for feeding coal to locomotives were in use in the 1920s.[7] Steam turbine-electric locomotive power was developed in 1938 by General Electric. GE abandoned the project in 1943 after results were unsatisfactory during trials with three railroads, however, Baldwin Locomotive Works built three steam turbine-electric locomotives for passenger service in 1948. They were expensive to operate and insufficiently reliable for their intended service, and were scrapped in 1950. Baldwin's steam turbine-electric program resulted in one more locomotive for freight service in 1954, which was also not successful in service.

US entry into World War II interrupted dieselization. The US Navy gained priority for diesel engines, curtailing their availability for railway use. No production of passenger locomotives was permitted by the War Production Board between September 1942 and February 1945. The petroleum crisis of 1942-43 made coal-fired steam more attractive, especially near the east coast. After the peak of the petroleum crisis and as wartime production of diesel engines hit its stride, increasing production of freight diesel locomotives was permitted. By the war's end, pent-up demand to replace dated and worn-out railway equipment was overwhelming. General Motors signed proprietary contracts with the major railroads, who were replacing their worn out wartime equipment with diesels. With the GM contracts came articles that GM would supply training, financing, and maintenance, to lower the hurdles in converting from steam to diesel.

The market share of steam locomotives dropped from 30% in 1945 to 2% in 1948.[8] The drop was most precipitous in passenger service, where modernization of equipment was imperative for image and cost reasons as railroads faced increasingly stiff competition from airplanes and the automobile. Norfolk and Western continued to champion steam, running steam passenger locomotives until 1959 and acquiring the last American steam locomotives built, a piston locomotive built in their own shop in 1953 and a steam turbine-electric locomotive built by Baldwin Locomotive Works in 1954.[9]

Due to the advantages of diesel locomotives, railroads in North America had retired 90% of their steam locomotives by the mid-1950s.[10][11][12] Also, major cities and their railyards became unhappy neighbors in post-war America. People were no longer content to endure the large amounts of soot and smoke that coal burning steam engines produced. Early diesels, while dirty by today's standards, were a gigantic improvement in air pollution over steam.

Steam engines lasted well into the late 1950s on major American railroads, and in isolated cases into the middle 1960s on small common carrier roads. The last steam locomotive fleet in everyday use (i.e. not a restored fleet) was retired in the late 1970s. Now they are only found in historical and sightseeing roles, where the steam engine is once again the star of the show. Retired steam engines, many of which were quite new when made obsolete, often found a second life in developing nations due to their cheap labor for maintenance and crewing, ready supplies of coal, and lack of environmental concern.

This list is a sample of some of the more prominent railroad companies' diesel traction conversions.

• Aberdeen and Rockfish Railroad - last steam locomotive retired in 1953
• Akron, Canton and Youngstown Railway - steam era ended in 1955
• Alabama, Tennessee & Northern - steam ended in 1952
• Alaska Railroad - last steamer, former USATC S160 2-8-0 #557 retired in 1964, making the ARR one of the last railroads in the U.S. to dieselise
• Alton and Southern Railway - a Union Pacific subsidiary, steam operations ended in 1950
• Ann Arbor Railroad - dieselised by 1952
• Atchison, Topeka, and Santa Fe Railroad - the last revenue steam operations occurred on August 27, 1957.[13] Dieselisation completed in 1959.
• Atlanta & West Point - last steam locomotives retired in 1954.
• Atlantic and Yadkin Railway - a small shortline operated independently by the Southern Railway from 1917 until it merged with the Southern in 1950, that was the last time a steam locomotive ran on the line.
• Atlantic Coast Line - dieselisation by 1954.
• Baltimore and Ohio Railroad - first diesel purchased in 1928. Dieselisation completed in April 1960 when the EM-1 2-8-8-4s dropped their fires for the last time.
• Bangor and Aroostook Railroad - last new steam locomotive purchased 1945, steam traffic ended in 1953
• Bessemer and Lake Erie Railroad - dieselisation complete in 1954
• Boston and Maine Railroad - end of steam in 1956.
• Boston and Albany Railroad - dieselization completed on March 7, 1951.
• Buffalo Creek and Gauley Railroad - last steam engine, 2-8-0 #4, ran on February 27, 1965.[14]
• Cadiz Railroad - Last steam locomotive to run on the line was 0-6-0 #205 on July 25, 1954.
• Carolina & Northwestern - a separately controlled company run by the Southern Railway; steam gone by 1948
• Central of Georgia - steam fleet retired in 1953, but 4-4-0 #349 and 4-6-0 #403 were still leased to the Talbotton Railroad at the time. #403 retired in 1957 and #349 was kept around on stand-by until 1961.
• Central of New Jersey - steam fleet retired in 1954
• Central Vermont - steam fleet retired by 1957
• Chesapeake and Ohio Railroad - dieselisation completed in 1957, however the railroad's fireless cookers continued service until 1965.
• Chattahoochee Valley Railway - By 1947, Baldwin 2-8-0 #21 became the last steam locomotive on the CHVRR. It was kept on stand-by and flood relieve service until it was retired from service in 1961.
• Chicago and Alton Railroad - dieselisation completed in 1952
• Chicago & Eastern Illinois - last steam in 1955
• Chicago & Illinois Midland - last steam locomotive retired in 1955
• Chicago & North Western - steam ended in 1956
• Chicago, Burlington and Quincy Railroad - first diesel 1934;[15] dieselisation completed in 1960 (but see Colorado & Southern, below)[16]
• Chicago, Peoria and St. Louis Railway - steam operations ended in 1952
• Chicago, Rock Island and Pacific Railroad - official dieselisation date was September 16, 1953[17]
• Clinchfield Railroad - steam phased out in 1954
• Colorado and Southern Railway - dieselisation completed with 2-8-0 #641 running its last train on October 11, 1962[16]
• Crab Orchard and Egyptian Railway - steam-using tourist line that added regular revenue freight service in 1977, dieselised in 1986.[18] Recognized by the AAR as the last US railroad of any kind to use steam locomotives in regular revenue service.
• Danville and Western Railroad - dieselization completed in the early 1950.
• Delaware and Hudson Railway - last steam in 1953
• Delaware, Lackawanna, and Western Railroad - dieselisation completed by 1953.
• Denver and Rio Grande Western Railroad - Standard gauge lines completed dieselisation in September 1956; narrow gauge lines ended revenue operation on August 31, 1968, never dieselizing.
• Detroit and Mackinac Railroad - this line dieselised early, retiring the last of its steam locomotives in 1948
• Detroit, Toledo & Ironton - steam ended in 1955
• Duluth and Northeastern Railroad - dieselized in 1964
• Duluth, Missabe & Iron Range - steam operations finished by 1962
• Duluth, South Shore & Atlantic - last steam locomotives written off the active roster in 1953
• East Tennessee & Western North Carolina - narrow gauge lines went down on October 16, 1950, never dieselising. Standard gauge steam went on for another 17 years until the Southern Railway traded two Rs-3s for the ET&WNC's last steam locomotives on December 8, 1967. Last steam locomotives to run in revenue service in Tennessee.
• Elgin, Joliet and Eastern Railway - first diesel 1937;[19] dieselisation completed in May 1949 [20][21]
• Erie Railroad - Steam phased out on March 17, 1954.
• Florida East Coast Railway - last steam locomotives removed from service in 1955
• Fort Worth and Denver Railroad - last steam locomotives retired in 1960
• Frisco Railway - steam fleet retired in 1952, however 46 steam locomotives were still kept on the active roster until August 1956.
• Georgia, Ashburn, Sylvester and Camilla Railway - The railway ran steam until 1948.[22]
• Georgia & Florida Railway - last steam locomotives retired by 1953
• Georgia Northern Railway - steam phased out in 1962
• Georgia Railroad - dieselised in 1955
• Grand Trunk Western Railway - one of the last railways in the US to dieselize; retired its last steam locomotives in 1961.
• Great Northern Railway - dieselisation completed in 1958
• Green Bay & Western - last steam locomotives delivered new in 1939; steam officially gone by the end of 1953
• Great Western Railway - steam used at least to 1965, possibly 1967
• Great Western Sugar Company - last steam operation in 1983, final ran for a ceremonial steam-up at the Fort Morgan plant in 1987; among the last industrial steam users in the US
• Gulf, Mobile, and Ohio Railroad - steam phased out by 1951
• Hampton and Branchville Railroad - steam operations ended in 1958.
• Illinois Central Railroad - dieselisation completed in 1960
• Interstate Railroad - last steam locomotive retired in 1955.
• Kansas City Southern Railroad - dieselization completed by 1954
• "The Katy" - steam fleet retired in 1951
• Kentucky and Tennessee Railway - The railroad was run by steam until the road purchased 3 S-2 diesel switchers from the D&RGW in February 1964.
• Lake Superior and Ishpeming Railroad - dieselised in 1962
• Lehigh and Hudson River Railway - dieselised in 1950
• Lehigh Valley Railway - steam fleet retired in 1951
• Litchfield and Madison Railway - last steam operation in 1954
• Live Oak, Perry & Gulf - steam phased out by 1955
• Long Island Railroad - last steam, ex-PRR locomotives, ran in late 1955
• Louisiana & Arkansas - last steam locomotives retired in 1954
• Louisville and Nashville Railroad - last steam locomotives dropped off the roster in November 1956, although 2-8-2 #1882 kept running on a branch line in Kentucky until 1957
• Magma Arizona Railroad - last steam locomotive retired from revenue service on September 4, 1968
• Maine Central Railroad - last steam locomotives retired in 1954, after the last run of number 470
• McCloud River Railroad - last steam locomotives retired in 1956
• Milwaukee Road - last new steam 1944; dieselisation completed in 1957
• Minneapolis and St. Louis Railway - last steam locomotive retired in 1951
• Minneapolis, Northfield & Southern - dieselised by 1953
• Mississippi Central Railroad - steam era ended in 1953
• Missouri Pacific Railroad - the last steam locomotives retired in November 1955.[23]
• Monon Railroad - dieselisation completed in 1949
• Monongahela Railroad - last steam on the line in 1954.
• Morehead & North Fork Railroad - dieselization completed on April 1, 1963.
• Moscow, Camden and San Augustine Railroad - Last steam run was January 1965.
• Nashville, Chattanooga & St. Louis - last steam operations on September 2, 1953
• Nevada Northern Railroad - last steam locomotive ran in 1961
• New Haven Railroad - dieselization completed in 1952, spurred on by steam restrictions in the vicinity of New York City
• New York Central Railroad - full-scale dieselization began in the late 1940s; final run of steam in regular service was on May 3rd, 1957[24]
• New York, Susquehanna and Western Railway - perhaps the first major railroad to dieselize, the "Susie-Q" had eliminated all of its steam locomotives in 1945.
• Nickel Plate Road - one of the last holdouts of the steam locomotive in America, retiring the last of its steam fleet in 1960
• Norfolk and Western Railway - last new steam in late 1953, first purchased diesel in 1955; marking the last US Class 1 railroad to dieselize; dieselisation completed on May 7, 1960.[9] However, some sources state that many Y series 2-8-8-2s were kept around on stand-by service as late as 1965.
• Norfolk Southern (original) - steam operations ended in January 1954
• Northern Pacific Railroad - last steam on the Northern Pacific was in 1960
• Northwestern Pacific - By 1957, 4-6-0 #112 was the last steam locomotive on the NWP. It later retired from service in 1962.
• Pennsylvania Railroad - last steam in regular operations was in 1957.[25] However, B6 class 0-6-0 switcher #5244 kept operating for the Union Transportation Company until July 1959.[26]
• Pittsburgh and Lake Erie Railroad - This short but very important Class 1 railroad completed its dieselization program in 1953.
• Reading Railroad - dieselization completed around 1957, however B-4a class 0-6-0ST switcher #1251 still operated on the active roster until it's retirement in February 1964.[27]
• Richmond, Fredericksburg and Potomac Railway - dieselization completed in 1952. However a huge number of 4-8-4s were leased to the Chesapeake & Ohio Railroad around this time. They were finally retired and scrapped in 1959.
• Rutland Railroad - last steam locomotives, the L-1 class 4-8-2s, retired in March 1955.
• St. Louis Southwestern - steam operations ended in 1953
• Savannah & Atlanta - steam was phased out in 1955, but 4-6-2 No. 750 still operated on work trains until 1962.
• Seaboard Air Line Railroad - mainline traffic dieselized by 1955
• Sierra Railroad - revenue steam operations concluded in 1955, three steam locomotives were kept for occasional excursion and film service.[28]
• Southern Pacific Railroad - dieselisation completed in 1958
• Southern Railway - dieselisation completed on June 17, 1953,[29] although some steam locomotives such as the As-11 and Ms-4 2-8-2s were on reserve service until 1954.
• Spokane, Portland & Seattle - the last steam locomotive retired in 1960.
• Tallulah Falls Railway - switched to diesel power in 1948. However, 2-8-0 #75 was temporarily re-instated in 1950 for the film I'd Climb the Highest Mountain
• Tennessee, Alabama & Georgia Railway - steam phased out by 1951
• Tennessee Central Railway - last steam operations in 1952, although a few 2-8-2s and 4-8-2s were still kept on stand-by service until March 1955
• Tennessee Railroad - dieselised in 1957
• Texas & Pacific - steam phased out in 1952; however, the T&P bought Fort Worth & Denver 2-8-2 #410 in the late 1950s as a source of backup power especially during floods. It was retired in 1962.
• Union Pacific Railroad - first diesel in 1934; last new steam in 1944;[30] last passenger steam run 1958; dieselisation completed in 1959; stand-by steam ended in 1962. However, steam locomotives UP 844, UP 3985 and UP 4014 remain on the railroad's roster as part of its excursion program, with 844 never being officially retired.
• Unadilla Valley Railway - The railroad purchased its first diesel in 1947, but steam power held on until 1956.
• Virginian Railway - fully dieselized in 1957, but a few steamers were still kept on standby service until January 1960.
• Virginia Blue Ridge Railway - last steam locomotive retired on August 1st, 1963.
• Wabash Railway - fully dieselized in 1956
• Western Maryland Railroad - dieselization on east of Hagerstown in 1949, end of steam system-wide on July 16th, 1954
• Western Pacific Railroad - dieselisation completed in 1953 (last steam operated on subsidiary Tidewater Southern)
• White Pass & Yukon Route Railroad - last new steam locomotives arrived in 1947; dieselisation complete on June 30, 1964.
• Winston-Salem Southbound Railway - steam ended in 1957.
• Wrightsville and Tennille Railroad - steam ended in 1962.

Main article: Railway electrification in the Soviet Union

Soviet leadership in the 1920s and 1930s had originally envisioned railway electrification as a key component of their industrialization, but by World War II only a small portion of their rail lines were electrified. Their project faced many challenges, including the high initial costs of electrification relative to traffic volume on long rail lines, high resource costs of early Soviet electrical power generation, and the urgent need to reconstruct after World War II. The postwar Soviet Union embarked upon a hybrid dieselization/electrification program, with electrification concentrated on shorter lines. Both dieselization and electrification proceeded slowly, with the last steam locomotives retired in 1975. At that time approximately 48% of freight tonnage was hauled by diesel and that share would decrease as electrification proceeded. As of 1990, approximately 30% of passenger traffic and 37% of freight tonnage was still hauled by diesel. Post-Soviet electrification was slowed by the economic collapse of the 1990s. Electrification was completed on the Trans-Siberian Railway in 2002 and on the Kirov Railway to Murmansk in 2005. Since 2003, less than 15% of Russian freight tonnage is hauled by diesel.

The majority of Japan's rail network had been electrified in the post-war years. In spite of this, more desolate railway lines, particularly on the northern island of Hokkaido continued to use surplus steam locomotives well into the mid-1970s. This was due to the limits and problems created by the then-nationalized rail network, Japanese National Railways (JNR). Japan also has large coal deposits as a natural resource. By 1970, most, if not all steam locomotives had been relegated to freight work, and by the time that complete dieselisation occurred, the remaining steam locomotives were used for branch line work and shunting duties and later were put out of use completely..

Diesel and electric locomotives started slowly replacing steam in 1950s. The last broad gauge (5' 6") steam locomotive built by CLW was a WG class locomotive named Antim Sitara (The last star), #10560, built in June 1970. The last meter gauge steam locomotive was a YG class built in 1972.[31] Steam was largely replaced in 1980s. The last scheduled steam operation was on 6 December 1995 on broad gauge. Last steam operation on narrow/meter gauge ended in 1999.[32]

Two heritage lines, the Darjeeling Himalayan railway and the Nilgiri mountain railway have retained steam service.

China, after experimenting with diesel locomotives since 1958, started regular production of diesel locomotives in 1969 but continued to produce steam locomotives into the late 1980s. The last mainline service with steam ended in 2005. Poor reliability of the first model of DF4 diesel locomotives, which became the subject of rude jokes between China Railway employees, slowed deployment and only 108 examples were produced between 1969 and 1976. Later passenger and freight versions of the DF4 proved more reliable, and variants continue to be produced to the present. Starting in the mid-1980s China was already looking beyond diesel towards electrification; as of 2004, 18,900 km of China's 74,200 km rail system were electrified. Planning for China's China's high speed rail system began during the 1990s.

• Advanced steam technology
• Electric vehicle — and the concept of transport electrification
• Hybrid vehicle

• Efficient energy use
• Energy policy
• Golden gimmick
• Pershing Map
• Suez Crisis

• Aramco
• Diesel
• Diesel engine
• Winter diesel

• Baldwin Locomotive Works
• Beeching axe
• General Motors streetcar conspiracy
• Woodham Brothers scrapyard in Barry, South Wales

• spelling differences