Editing 4-8-4 (section)

==Usage==

===Australia===
A total of twenty-three {{nowrap|4-8-4}} locomotives operated in Australia, built to three distinct designs.

In 1929, the ten {{RailGauge|5ft3in|allk=on}} gauge [[South Australian Railways]] 500 class {{nowrap|4-8-2}} Mountain types of 1926 were equipped with steam boosters in the form of small auxiliary steam engines to increase their power. This necessitated the replacement of their two-wheel trailing trucks with four-wheel [[bogie]]s. The booster contributed an additional {{convert|8000|lbf|kN|abbr=off}} to the tractive effort and permitted an increase in the locomotive's load across the [[Mount Lofty Ranges]] to 540 tons. In their new {{nowrap|4-8-4}} configuration, they were reclassified to 500B class.<ref name="Australian 500B">[http://www.natrailmuseum.org.au/exhibits/nrm_504.html National Railway Museum, Port Adelaide - 500B-class 4-8-4 steam locomotive No.504 "TOM BARR-SMITH"] - retrieved 1 November 2006 {{webarchive |url=https://web.archive.org/web/20060819070609/http://www.natrailmuseum.org.au/exhibits/nrm_504.html |date=August 19, 2006 }}</ref>

[[File:520 class loco-South Australia-1984.jpg|thumb|[[South Australian Railways 520 class]]]]
In 1943, the first of twelve streamlined South Australian Railways [[520 class steam locomotive|520 class]] locomotives were delivered from the Islington Workshops in [[Adelaide]]. Although they were large locomotives, they were designed to run on lightly constructed {{convert|60|lb/yd|adj=on}} track, with the engine's weight being spread over eight axles. Their {{convert|66|in|mm|0|adj=on}}-diameter coupled wheels were specially balanced for {{convert|70|mph|km/h|adj=on}} running.<ref name="Australian 520">[http://www.natrailmuseum.org.au/exhibits/nrm_523.html National Railway Museum, Port Adelaide - 520-class 4-8-4 steam locomotive No.523 "Essington Lewis"] - retrieved 1 November 2006 {{webarchive |url=https://web.archive.org/web/20060819065240/http://www.natrailmuseum.org.au/exhibits/nrm_523.html |date=August 19, 2006 }}</ref>

[[File:H220-Newport.jpg|thumb|left|[[Victorian Railways]] [[Victorian Railways H class|H220 ''Heavy Harry'']]]]
The [[Victorian Railways H class|H class]] three-cylinder {{nowrap|4-8-4}} of the [[Victorian Railways]], built in 1941, was designed for heavy passenger work on the line between [[Melbourne]] and Adelaide. Nicknamed ''Heavy Harry'', it was the largest steam locomotive built in Australia and, after the [[New South Wales D57 class locomotive|NSWGR D57]] 4-8-2 and the [[South Australian Railways 500 class (steam)|South Australian Railways 500/500B class]], the third-most-powerful non-articulated locomotive. It was one of the five Australian classes of three-cylinder {{nowrap|4-8-4}} locomotives.

Construction of three locomotives commenced at the [[Newport Workshops]] in 1939 and three sets of frames were manufactured. Although work was halted due to the outbreak of the [[World War II|Second World War]], a shortage of motive power caused by increased wartime traffic resulted in authorisation being given for the completion of class leader H220. The locomotive went into service on 7 February 1941, but remained the sole member of the class because the other two partly-built locomotives were never completed. Since the necessary upgrades to the Adelaide line was deferred, H220 operated only on the line between Melbourne and [[Albury]] in [[New South Wales]].<ref name="Dunn3">{{cite book |last=Dunn |title=Super Power on the VR: Victorian Railways 4-8-4 'H' Class Pocono |publisher=Train Hobby Publications |year=2006 |location=Melbourne |isbn=1-921122-07-2 |page=15|display-authors=etal}}</ref><ref>[http://www.steamtrainartist.com/text_steam_train_PL1058.html Steamtrainartist.com - Victorian Railways H Class 4-8-4] - retrieved 1 November 2006 {{webarchive |url=https://web.archive.org/web/20070303140508/http://www.steamtrainartist.com/text_steam_train_PL1058.html |date=March 3, 2007 }}</ref>

===Brazil===
To meet the acute locomotive shortages in Brazil after the Second World War, 27 scaled down American {{nowrap|4-8-4}} Niágara locomotives were ordered by the Brazilian {{lang|pt|i=unset|Departamento Nacional de Estradas de Ferro}} (DNEF) from ALCO in 1946. These locomotives were supplied to the {{lang|pt|i=unset|[[Augusto Pestana (politician)#Congressman, founder of the Railway Company of Rio Grande do Sul and State Secretary|Viação Férrea do Rio Grande do Sul]]}} (VFRGS), which then purchased another fifteen directly from ALCO in 1947. They were designated the 1001 class. In 1956 and 1957, some of them were sold to [[Bolivia]]. The Baldwin Locomotive Works supplied similar {{RailGauge|1000mm|allk=on}} {{nowrap|4-8-4}} locomotives to the {{lang|pt|i=unset|Rede Mineira de Viação}} (RMV no. 601 to 604), the {{lang|pt|i=unset|Rede de Viação Paraná-Santa Catarina}} (RVPSC no. 801 to 806) and the {{lang|pt|i=unset|Noroeste do Brasil}} (NOB no. 621 to 623).<ref>{{cite web |title=Centro-Oeste |url=http://ar.geocities.com/centrooeste/pages/50ejjcGelsa.htm |archive-url=https://web.archive.org/web/20091027000448/http://ar.geocities.com/centrooeste/pages/50ejjcGelsa.htm |archive-date=2009-10-27 |url-status=dead |access-date=2008-11-26 }}</ref>

After his retirement from the {{lang|fr|i=unset|Société nationale des chemins de fer français}} ([[SNCF]]) in [[France]], French engineer [[André Chapelon]] was appointed as the chief designer of {{RailGauge|1000mm|allk=on}} {{nowrap|4-8-4}} locomotives at the French state-owned sales consortium {{lang|fr|i=unset|Groupement d'exportation de locomotives en Sud-Amérique}} (GELSA). In 1949, a contract was signed between DNEF and GELSA for the construction of 24 {{nowrap|4-8-4}} locomotives with a {{convert|13|t|LT ST|1|abbr=off}} axle load. The order also included 66 {{nowrap|2-8-4}} Berkshires. All ninety locomotives were delivered by January 1953.

The 24 class 242F Niágara locomotives were built by [[Société de Construction des Batignolles]] ({{ill|Batignolles-Châtillon|fr}}). They were two-cylinder simple expansion locomotives, designed to burn poor quality local coal with a low calorific thermal value, with coupled wheels of {{convert|60|in|mm|0|abbr=off}} diameter and a grate area of {{convert|58|sqft|m2|abbr=off}}. They were coupled to big tenders which a coal capacity of {{convert|18|t|LT ST|1|abbr=off}}. The [[Belpaire firebox]] included a combustion chamber and the boiler pressure was a high {{convert|18|atm|kPa psi|abbr=off}}. One member of the class was tested on the {{RailGauge|1000mm|allk=on}} [[Reseau Breton]] line in France before being shipped to Brazil.<ref>[http://thierry.stora.free.fr/techdat3_f.htm#Brazil Locomotives Compound "Type Français" - Informations Techniques page 3]</ref>

The DNEF allocated the locomotives to four of Brazil's state railways. Under Brazilian railway conditions, these modern locomotives were not popular with local railwaymen and were not used as much as had been hoped. Their maximum axle load of {{convert|13|t|LT ST|1|abbr=off}} restricted their usefulness, as did their long tenders. In some places the [[Railway turntable|turntables]] were too short to turn the locomotives and they had to be turned on [[Wye (rail)|triangles]]. In addition, the building specifications had called for a locomotive capable of a maximum speed of {{convert|80|km/h|mph|abbr=off}} and the ability to negotiate curves with a [[Minimum railway curve radius|minimum radius]] of {{convert|80|m|ft|abbr=off}}. This last point proved to be a source of contention when it was later discovered that the curves in some places were of less than {{convert|50|m|ft|abbr=off}} radius. As a consequence, the locomotives were involved in a number of derailments.

In the late 1960s, they were relegated down from first class passenger trains. Some locomotives, allocated to [[Southern Brazil]], were also tried in [[Bolivia]].

===Canada===
Since the Canadian mainlines were generally laid with {{convert|115|lb/yd|kg/m|adj=on}} rail, Canadian {{nowrap|4-8-4s}} were heavy and weighed in with axle loads up to {{convert|31.3|ST}}.

When the [[Canadian National Railway]] (CN) introduced its first {{nowrap|4-8-4}} in 1927, it used the name "[[Confederation locomotive|Confederation]]" for the type, to celebrate the 60th anniversary of the Canadian Confederation. The CN employed a total of 160 Confederation locomotives.
[[File:Canadian Northern 6400 1939.jpg|thumb|[[Canadian National Railway|A Canadian National Railway]] [[Confederation locomotive|U-4-a]], a streamlined 4-8-4 of which one, [[Canadian National 6400]], is preserved. The other 7 preserved examples are non streamlined.]]
* Altogether forty locomotives were delivered in 1927, twenty Class U-2-a from the [[Canadian Locomotive Company]] and twenty Class U-2-b from the [[Montreal Locomotive Works]] (MLW).
* Another twenty Class U-2-c came from MLW in 1929 and another five Class U-2-d, also from MLW, in 1936.
* The CN U-4a was one of the few streamlined Confederation types, with five locomotives built by MLW and also introduced in 1936. U-4a No.&nbsp;6400 achieved fame in 1939 by heading the royal train (see [[1939 royal tour of Canada]]) and being exhibited at the [[1939 New York World's Fair|New York World's Fair]] in the same year.
* Between 1940 and 1944, a total of ninety more Confederation locomotives, built in four batches, were added to the CN roster.<ref name="Northern Type CN">{{Cite web |url=http://www.steamlocomotive.com/northern/?page=cnr |title=Grand Trunk Western / Canadian National 4-8-4 "Northern" Type Locomotives |access-date=2012-11-17 |archive-url=https://web.archive.org/web/20140728133705/http://www.steamlocomotive.com/northern/?page=cnr |archive-date=2014-07-28 |url-status=dead }}</ref>

The Canadian Pacific Railway (CPR) experimented with the {{nowrap|4-8-4}} wheel arrangement in 1928, when two K-1a class locomotives were built in its [[CPR Angus Shops|Angus shops]] in [[Montreal]], the first locomotives to be built with a one-piece cast-steel frame in Canada. However, since the CPR mainlines were built to high standards, the railway preferred to develop the {{nowrap|4-6-4}} Hudson type for passenger work since it gave adequate power and was cheaper to maintain, while a ten-coupled type, the {{nowrap|2-10-4}} Selkirk, was adopted for heavy-duty work. Nevertheless, although the two CPR Northerns remained orphans, they proved their worth continuously for 25 years on overnight passenger trains between Montreal and [[Toronto]]. Before their retirement in 1960, they were converted to oil-burners and worked freight trains in the prairie provinces.<ref>James A. Brown and Omer Lavallee. ''Hudson Royalty''. Trains Magazine, August 1969.</ref><ref name="Northern Type CP">{{Cite web |url=http://www.steamlocomotive.com/northern/?page=cp |title=Canadian Pacific 4-8-4 "Northern" Type Locomotives |access-date=2012-11-17 |archive-url=https://web.archive.org/web/20121126081425/http://www.steamlocomotive.com/northern/?page=cp |archive-date=2012-11-26 |url-status=dead }}</ref>

===Chile===
In 1936, the German builder [[Henschel & Son]] supplied ten {{RailGauge|5ft6in|allk=on}} gauge {{nowrap|4-8-4}} locomotives to the {{lang|es|i=unset|Ferrocarriles del Estado}} (State Railways or FdE) of [[Chile]], designated the {{lang|es|Tipo 100}}. They were called {{lang|es|Super Montañas}} (Super Mountains), since they followed the {{lang|es|[[EFE Tipo 80|Tipo 80]]}} {{nowrap|4-8-2}} Mountain that was introduced six years earlier. They were equipped with mechanical stokers and Vanderbilt tenders and weighed 185 tonnes in working order. On test, they produced {{convert|2355|ihp|abbr=off}} at a coal consumption of {{convert|34|kg/km|abbr=off}} and a water consumption of {{convert|274|L|abbr=off}} per kilometre. The design was not repeated, however, and the FdE returned to the {{nowrap|4-8-2}} wheel arrangement with its subsequent acquisitions. The {{lang|es|Tipo 100}} was used on the line from Almeda to [[Talca]] until it was replaced by diesels in 1969. One of them, no. 1009, is preserved in the Santiago Railway Museum.<ref>{{Cite web |url=http://www.lcgb.org.uk/html/santiagomuseum.htm |title=Railway Pages of David Pendlebury & Chris Cairns. Museo Ferroviario de Santiago - Santiago Railway Museum |access-date=2008-11-26 |archive-date=2009-10-12 |archive-url=https://web.archive.org/web/20091012020645/http://www.lcgb.org.uk/html/santiagomuseum.htm |url-status=dead }}</ref>

===China===
[[File:KF7 steam locomotive at Qishuyan.jpg|thumb|China Railways KF Class]]
In 1933, the [[Beijing–Hankou Railway]] in [[China]] needed new locomotives for their [[Guangzhou]] to [[Shaoguan]] line, where gradients of around two percent, curves with less than {{convert|250|m|ft|abbr=off}} radius and low capacity bridges existed. The requirement was therefore for a locomotive with high tractive effort and a low axle load. In 1935 and 1936, 24 600-series {{nowrap|4-8-4}} locomotives, designed and built in the United Kingdom by [[Vulcan Foundry]], were delivered to the railway. The locomotives represented a significant improvement over previous designs and incorporated a more efficient E-type superheater and duplex steam valve to allow better steaming without enlarging the boiler, while the {{nowrap|4-8-4}} wheel arrangement allowed better weight distribution.

When the [[Changsha]]–Guangzhou Railway was completed in October 1936, the locomotives were transferred to operate over the northern section between [[Hankou]] and Changsha on this new mainline, which connected Guangzhou with [[Tianjin]] and [[Beijing]].

Following the establishment of the People's Republic of China, the locomotives were designated the [[China Railways KF]] class. Some of the locomotives survived in service until the early 1970s. One of them, no. 607, is preserved at the [[National Railway Museum]] in the United Kingdom<ref>[https://archive.today/20120910170131/http://www.nrm.org.uk/OurCollection/LocomotivesAndRollingStock/CollectionItem.aspx?objid=1987-7001 National Railway Museum - Chinese Government Railways Steam Locomotive 4-8-4 KF Class No 7]</ref>  and another is in China at the [[Beijing Railway Museum]].<ref>{{citation| url = http://www.railwaysofchina.com/preserved.htm| work = www.railwaysofchina.com| title = Preserved locomotives.| access-date = 25 May 2012| archive-url = https://web.archive.org/web/20110715150940/http://www.railwaysofchina.com/preserved.htm| archive-date = 15 July 2011| url-status = dead}}</ref>

===Czechoslovakia===
The 60 {{nowrap|4-8-4}}T tank engines of [[Czechoslovak State Railways]]' [[ČSD Class 477.0|477 class]] represent the ultimate development of the [[ČKD|CKD]] 4-8-2 tender locomotive, but added a four-wheel trailing truck as part of the conversion to a tank locomotive.  One of five classes of three cylinder {{nowrap|4-8-4}} locomotives known, they were the last steam locomotives delivered to the Czechoslovak State Railways, with the last group built in 1955. Used primarily in local passenger service, they were pulling regularly timetabled trains as late as 1981. 
[[File:477_Farbe.jpeg|thumb|CSD 477.043 in the Railway Museum at Lužná u Rakovníka]]
Three are preserved, as of 2018 two of them were still operational (013 and 043).<ref>Výhrevna Vrútky, [https://vyhrevna-vrutky.sk/zeleznica-pre-deti-2018/ Železnica pre deti 2018], 5 June 2018, with photos of 477.013</ref><ref>[[České dráhy]], Železničář, 11 April 2019, page 4, mentions 477.043 pulled a train with hundreds of passengers in March 2019</ref><ref>Annual report of Národní technické muzeum for calendar year 2009, mentions 477.060 was on display in [[Augsburg Railway Park]]</ref>

===France===
The lone prototype, numbered 242A1, of the {{lang|fr|i=unset|Société Nationale des Chemins de fer Français}} (SNCF) was one of the five known classes of three-cylinder {{nowrap|4-8-4}} locomotives. It also had the distinction, along with an experimental high pressure locomotive of the [[New York Central Railroad]] in the United States, of being one of the two compound {{nowrap|4-8-4s}}. It was rebuilt by [[Andre Chapelon]] from the unsuccessful 1932 three-cylinder {{nowrap|4-8-2}} simple expansion locomotive no. 241.101 of the {{lang|fr|i=unset|[[Chemins de Fer de l'État]]}} into a {{nowrap|4-8-4}} [[compound locomotive]]. This remarkable locomotive achieved extraordinary power outputs and efficiency in coal and water consumption, but no further examples were built since the SNCF focused on electric traction for its future motive power development.<ref>{{cite web|url=http://thierry.stora.free.fr/english/techdat2.htm#242A1_1|title=242 A 1, three cylinders 4 8 4| work=French Compound Locomotives' Homepage| year=2002| author=Stora, T.| access-date=2008-02-08}}</ref>

[[File:SNCF Class 242 A1.jpg|thumb|left|SNCF No. 242A1]]
No. 242A1 was put through trials on many test runs which showed that this locomotive was equal in power output to the existing SNCF electric locomotives at the time. Here, for the first time in Europe, was a steam locomotive with a {{convert|20|t|LT ST|1|abbr=off}} axle load which was not only at least as powerful as the most powerful existing high-speed electric locomotive, but which could repeatedly achieve its maximum power without any mechanical trouble. Developing {{convert|5300|ihp|abbr=off}} and with {{convert|65679|lbf|kN|0|abbr=off}} of peak tractive effort and {{convert|46225|lbf|kN|0|abbr=off}} of mean tractive effort; nothing in Europe could match it.

While no. 242A1 was being tested, electrical engineers were designing the locomotives for the {{convert|512|km|mi|adj=mid|-long|abbr=off}} line between [[Paris]] and [[Lyon]], which was to be electrified. An electric locomotive that was to be slightly more powerful than the successful Paris to [[Orléans]] 2-D-2 type electric locomotive was being contemplated. When the test results of no. 242A1 became known, however, the design was hurriedly changed to incorporate the maximum capacity possible with a {{convert|23|t|LT ST|1|abbr=off}} axle load, resulting in the {{convert|144|t|LT ST|1|abbr=off}} 9100 class with a power output of more than {{convert|1000|hp|abbr=off}} more than that of the original design.

The performances of the [[:fr:Mistral (train)|''Mistral'']] and other heavy passenger express trains would therefore not have been so outstanding if no. 242A1 had not existed and Andre Chapelon therefore indirectly influenced French electric locomotive design. In addition, no. 242A1 demonstrated the suitability of the Sauvage-Smith system of compounding for French conditions and the designs for future French steam locomotives that were prepared but never produced, were to make use of the Sauvage-Smith compounding system.

In service, no. 242A1 was allocated to the [[Le Mans]] depot and, between 1950 and 1960, it hauled express trains over the {{convert|411|km|mi|abbr=off}} between Le Mans and [[Brest, France|Brest]]. It did not remain in service long, however, and was withdrawn and scrapped in 1960.

===Germany===
In 1939, the [[Deutsche Reichsbahn]] placed two prototype three-cylinder [[DRB Class 06]] 2D2-h3 heavy express locomotives in service, built by [[Krupp]] in 1938. Along with the lone 242A1 of the {{lang|fr|i=unset|Société Nationale des Chemins de fer Français}} (SNCF) and the lone Victorian Railways H class in Australia, it was one of the five known classes of three-cylinder {{nowrap|4-8-4}} locomotives. Due to the outbreak of the Second World War and construction problems, only the two locomotives were produced.

With three {{convert|520|by|720|mm|in|2|abbr=off}} cylinders, large {{convert|2000|mm|in|2|abbr=off}} diameter coupled wheels, a high {{convert|280|psi|abbr=off}} boiler pressure and {{convert|55800|lbf|kN|abbr=off}} of tractive effort, they were capable of a maximum speed of {{convert|140|km/h|mph|abbr=off}} and could haul a 650 tonne train at {{convert|120|km/h|mph|abbr=off}}. Many parts, such as the boiler, were standardised with that of the [[DRG Class 45]] heavy freight locomotive. The streamlined Class 06, the only German {{nowrap|4-8-4}}, was the biggest steam locomotive ever built in Germany. The two locomotives were shedded in [[Frankfurt]] and were placed in service on the line to [[Erfurt]]. No. 06.002 was bombed and destroyed during the hostilities and no. 06.001 survived until 1951, when it was retired and scrapped.<ref>[http://www.dbtrains.com/en/locomotives/epochII/BR06 dbtrains.com - BR 06] - retrieved 1 November 2006</ref>

The boiler of both the 06 and 45 were designed along the lines of [[Robert Garbe]] and [[Richard Paul Wagner|Richard Paul "Kunibald" Wagner]], who held that a [[Firebox (steam engine)#Combustion chamber|combustion chamber]] or double-expansion [[compound steam engine]]s were unnecessary when using [[superheated steam]]. While the DB railways in the FRG salvaged the Class 45 design by fitting it with a badly-needed [[mechanical stoker]], there was no need for the powerful Class 06 Express locos; when express traffic resumed, [[DB Class V 200]] and [[DB Class E 10]] Diesel-hydraulic and AC electric engines made any investment into pre-World War II steam engines unacceptable for the DB leadership even though [[Friedrich Witte]] or [[Adolph Giesl-Gieslingen]] proposed many improvements.

===Mexico===
In 1946, the {{lang|es|i=unset|[[Ferrocarriles Nacionales de México]]}} (N de M) placed orders with American Locomotive Company and Baldwin Locomotive Works for sixty Niágara locomotives for use on its principal express passenger services on upgraded lines, but the order was reduced to 32 in favour of diesel-electric locomotives. These QR-1 class locomotives were used mainly on lines north of [[Mexico City]] and were nicknamed {{lang|es|La Maquina}}. All were taken out of service in the late 1960s. Most survived and  No. 3028, although not in operating condition, was stored on the deadline at the [[New Hope and Ivyland Railroad]] in [[New Hope, Pennsylvania]]. {{Citation needed|date=November 2012}}

===New Zealand===
New Zealand adopted the narrow {{RailGauge|3ft6in|lk=on}} gauge to minimise railway construction costs and, due to the mountainous terrain, the [[loading gauge]] was restricted to a maximum height of {{convert|11|ft|6|in|m|abbr=off}} and width of {{convert|8|ft|6|in|m|abbr=off}}, making it one of the most restrictive loading gauges in the world. While this undoubtedly reduced the cost of building the two hundred-odd tunnels on the railway system, it posed major problems for locomotive designers which were exacerbated by an axle load limit of {{convert|14|LT|ST t|1|abbr=off}}.<ref name="NZR 19th Century">[http://www.techhistory.co.nz/19thcentury/Steam.htm The Nineteenth Century Heritage: The Steam Railways]</ref>

After the [[Soviet Union]] and [[South Africa]], the [[New Zealand Railways Department]] (NZR) had the largest fleet of {{nowrap|4-8-4}} locomotives outside North America, with 71 similar locomotives in the [[NZR K class (1932)|K class]], [[NZR KA class|K<sup>A</sup> class]] and [[NZR KB class|K<sup>B</sup> class]].<ref name="NZR 19th Century"/>

The K class was designed by R.J. Gard to the requirements of Locomotive Superintendent P.R. Angus and was built locally at the [[Hutt Workshops]] of the NZR. The first locomotives were delivered during the depths of the [[Great Depression]] in 1932. The {{convert|47|sqft|m2|abbr=off}} grate and comparatively large boiler was slung low on a narrow frame to keep within the height restrictions, and width restrictions were adhered to with sloped cab sides and the mounting of two single stage air compressors in front of the smokebox.<ref name="NZR 19th Century"/><ref>[http://www.ipenz.org.nz/heritage/itemdetail.cfm?itemid=55 IPENZ Engineers New Zealand: Engineering Heritage New Zealand] - retrieved 1 November 2006</ref>

[[File:Locomotive Ka 942.jpg|thumb|left|NZR K<sup>A</sup> class no. 942]]
After the construction of thirty K class locomotives, the NZR developed the design to strengthen the frame and introduced other improvements, such as roller bearings on all axles and ACFI ({{lang|fr|Accessoires pour les Chemins de Fer et l'Industrie}}) feedwater heaters. Introduced from 1939, they were also built in NZR workshops, most of them with streamlined shrouding to cover the external pipe work of their feedwater heater systems. The first 35 locomotives were designated K<sup>A</sup> class and worked on the North Island mainlines with the older K class locomotives.<ref name="NZR 19th Century"/>

Six more were built, designated K<sup>B</sup> class, for service on the steeply graded Midland line on the South Island. These locomotives were equipped with trailing truck boosters, which raised their tractive effort by {{convert|6000|lbf|abbr=off}}.<ref name="NZR 19th Century"/>

On occasion, these {{nowrap|4-8-4s}} recorded speeds up to {{convert|75|mi/h|km/h|abbr=off}}. The streamlining shrouds of the K<sup>A</sup> and K<sup>B</sup> classes were removed in the late 1940s when the ACFI feedwater heaters were replaced with exhaust steam injectors. The last of these locomotives was withdrawn in 1968 due to [[dieselisation]]. Seven have been preserved, K class numbers 900, 911 and 917, K<sup>A</sup> class numbers 935, 942 and 945 and K<sup>B</sup> class no. 968.<ref>[http://www.silverstreamrailway.org.nz/index.php?option=com_content&task=view&id=49&Itemid=50 Silver Stream Railway – Heritage Railway Museum and Steam Train Rides]</ref><ref>[http://www.steaminc.org.nz/ Steam Incorporated, Paekākāriki, New Zealand]</ref>

{{Clear}}

===South Africa===
[[File:SAR Class 25NC 3410 Sannaspos - 040799.jpg|thumb|SAR Class 25NC no. 3410]]
Between 1953 and 1955, the South African Railways (SAR) placed fifty [[South African Class 25NC 4-8-4|Class 25NC {{nowrap|4-8-4}}]] Northern locomotives in service. Designed under the direction of Chief Mechanical Engineer L.C. Grubb, eleven of these locomotives were built by [[North British Locomotive Company]] (NBL) and 39 by Henschel & Son. They were tended by [[South African type EW1 tender|Type EW1 tenders]] which rode on six-wheeled bogies. Two versions of the same locomotive were built, the Class 25NC being the non-condensing version, hence the "NC" suffix to the class number.<ref name="Holland 2">{{Holland-Vol 2|pages=108–111}}</ref><ref name="Paxton-Bourne">{{Paxton-Bourne|pages=77–78}}</ref>

[[File:3511 - Hartswater 240481.jpg|thumb|left|SAR Class 25 no. 3511]]
Ninety [[South African Class 25 4-8-4|Class 25]] condensing locomotives were introduced simultaneously, acquired as a means to deal with the shortage of adequate supplies of suitable locomotive water in the arid [[Karoo]]. The design work on the engine's condensing apparatus and the enormous condensing tender was carried out by Henschel, who built one locomotive complete with tender as well as sixty of the condensing tenders, to which they held the patent. The other 89 condensing locomotives and thirty tenders were built by NBL.<ref name="Holland 2"/><ref name="Paxton-Bourne"/>

[[File:SAR Class 25 3511 (4-8-4) Tender.JPG|thumb|Type CZ condensing tender]]
The [[South African type CZ tender|Type CZ condensing tenders]] were slightly longer than their engines. One-third of the total length of the tender was taken up by the water tank and coal bunker, while the rest was taken up by eight large radiators on each side, cooled by five steam-driven roof-mounted fans. Roller bearings were used throughout on all these locomotives, including the coupling and connecting rods, the crosshead gudgeon pins as well as the three-axle bogies of both the standard and condensing tenders. The leading bogies and coupled wheels had Cannon-type axle boxes. The cylinders and frames were cast in one piece, while the steel cylinders and steam chests were fitted with cast iron liners. The tender frames of both locomotive types were also one-piece steel water-bottom castings. Since they were entirely mounted on roller bearings, very little effort was required to move these big locomotives.<ref name="Holland 2"/><ref name="Paxton-Bourne"/>

On the condensing locomotives, spent steam was recycled and condensed back to water for repeated use. Since the steam was not expelled up the chimney, the smokebox contained a steam turbine-driven fan beneath the chimney to keep the draught going. Visual evidence of this altered and slightly longer smokebox is the locomotive's banjo-face smokebox front. The condensing system proved extremely efficient and reduced water consumption by as much as 90% by using the same water up to eight times over, which gave the Class 25 a range of {{convert|800|km|mi|abbr=off}} between water refills. In addition, the hot condensate feedwater resulted in significantly reduced coal consumption.<ref name="Holland 2"/>

[[File:SAR Class 25NC 3480 (4-8-4) Tender.JPG|thumb|Type EW2 {{lang|af|Worshond}} tender]]
However, the Class 25 was a complex locomotive that required high maintenance, especially on the turbine blower fans in the smokebox, whose blades needed to be replaced frequently due to damage by solid particles in the exhaust. The equally complex condensing tender also required frequent maintenance. Between 1973 and 1980, partly motivated by the spread of electric and diesel-electric traction, all but three of the locomotives were converted to free-exhausting and non-condensing locomotives and reclassified to Class 25NC. In the process their condensing tenders were also rebuilt to ordinary coal-and-water tenders by removing the condensing radiators and roof fans and replacing it with a massive round-topped water tank. Since the tenders were built on single cast-steel main frames, it was impractical to attempt to shorten them. Locomotives with these rebuilt [[South African type EW2 tender|Type EW2 tenders]] were soon nicknamed {{lang|af|Worshond}} (Sausage dog or Dachshund).<ref name="Durrant">{{Durrant-Twilight|pages=107–109, 194–198}}</ref>

[[File:3450 - Pretoria 250481.jpg|thumb|left|Class 26 ''Red Devil'' no. 3450]]
The [[South African Class 26 4-8-4|Class 26]], popularly known as the ''Red Devil'', was rebuilt from Henschel-built Class 25NC no. 3450 by mechanical engineer [[David Wardale]]. The rebuilding took place at the Salt River shops of the SAR in [[Cape Town]] and was based on the principles developed by Argentinian mechanical engineer [[Livio Dante Porta]]. The primary objectives of the modifications were to improve the combustion and steaming rate to reduce the emission of wasteful black smoke and to overcome the problem of clinkering. This was achieved by the use of a Gas Producer Combustion System (GPCS), which relies on the gasification of coal on a low temperature firebed so that the gases are then fully burnt above the firebed. The GPCS minimises the amount of air being drawn up through the firebed, the main source of air required for combustion being through ancillary air intakes on the firebox sides above the firebed.<ref name="Ultimate_Steam">[http://www.trainweb.org/tusp/wardale.html The Ultimate Steam Page]</ref><ref name="Rooinek">[http://www.martynbane.co.uk/modernsteam/dw/rooinek/rooinek.html South Africa's 'Red Devil']</ref><ref name="GPCS">[http://www.trainweb.org/tusp/firebox.html Gas Producer Combustion System (GPCS)]</ref>

The modified locomotive became the only Class 26. Compared to an unmodified Class 25NC, the ''Red Devil'' achieved a 28% measured saving on coal and a 30% measured saving on water, measured during freight service, and a 43% increase in drawbar power based on the maximum recorded drawbar power. Its approximate maximum range in full load freight service on 1% to {{frac|1|1|4}}% grades was {{convert|700|km|mi|abbr=off}} based on its coal capacity, and {{convert|230|km|mi|abbr=off}} based on its water capacity. The maximum recorded freight load hauled relative to gradient was {{convert|900|t|abbr=off}} on 2% grades, and it could haul a {{convert|650|t|abbr=off}} passenger train at a constant speed of {{convert|100|km/h|mph|0|abbr=off}} on 1% grades. The ''Red Devil''{{'s}} great power, however, also turned out to be its one weakness. The Class 25NC had already proven to be on the slippery side and the much more powerful Class 26, with essentially still the same dimensions as the Class 25NC, was even worse. It was a poor performer at starting or at low speeds on steep gradients.<ref name="Durrant"/><ref name="Ultimate_Steam"/><ref name="Rooinek"/>

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===Soviet Union===
Outside North America, the largest fleet of {{nowrap|4-8-4}} locomotives was the Class P36 of the {{lang|ru-Latn|Sovetskie Zheleznye Dorogi}} (SZhD) or [[Soviet Railways]], of which 251 were built by the [[Kolomna]] locomotive works between 1949 and 1956. As the last Soviet standard class steam locomotive, the Class P36 shared some common components and design attributes with earlier standard Soviet designs such as the L class [[2-10-0|{{nowrap|2-10-0}} Decapod]] type and LV class [[2-10-2|{{nowrap|2-10-2}} Santa Fe]] type, as well as some common attributes with the P34 class [[2-6-6-2|{{nowrap|2-6-6-2}}]] Mallet and P38 class [[2-8-8-4|{{nowrap|2-8-8-4}} Yellowstone]] type Mallet. For example, the P36 and LV classes shared the same [[feedwater heater]], made by the [[Bryansk]] machine factory. Apart from a trio of fully streamlined {{nowrap|4-6-4}} Baltic-type locomotives, they were the only semi-streamlined steam locomotives built in Russia. {{Citation needed|date=November 2012}}

[[File:Passenger steam locomotive P36-001 (01).jpg|thumb|Class P36-0071]]
The [[Russian locomotive class P36|Class P36]] was one of the best passenger steam locomotive classes built in the Soviet Union. They had boilers with {{convert|243.2|m2|sqft|abbr=off}} of heating surface that had a working boiler pressure of {{convert|1.5|MPa|psi|abbr=off}}. Russian-designed roller bearings were fitted throughout and the boilers were designed to provide a continuous steaming capacity of {{convert|57|kg|abbr=off}} per {{convert|1|m2|sqft|abbr=off|spell=in}} of heating surface in the boiler. With its {{convert|575|by|800|mm|in|1|abbr=off}} [[Cylinder (engine)|cylinders]] and {{convert|1850|mm|in|2|abbr=off}} diameter coupled wheels, it could easily attain speeds up to {{convert|125|km/h|abbr=off}} with passenger trains of up to {{convert|800|t|abbr=off}}.{{Citation needed|date=November 2012}}

The Class P36 first appeared on the ''[[Oktyabrskaya Railway]]'' (October Railway) to haul principal express trains between [[Moscow]] and [[Saint Petersburg|Leningrad]], but they did not remain on this {{convert|650|km|abbr=off}} mainline long. Diesels took over after only a few years and the P36 class locomotives were transferred to other lines and depots, such as the Moscow–[[Kursk]] and Moscow–[[Ryazan]] lines, [[Kalinin, Russia|Kalinin]], [[Krasnoyarsk]], [[Belarusian Railway]], [[Melitopol]] depot, Kuibyshev and [[Alexandrov (town)|Alexandrov]] depot. {{Citation needed|date=November 2012}}

Later, when electrification and dieselisation expanded, many of the Class P36 locomotives were transferred to work on the [[Lviv]], [[Russian Far East|Far East]], Eastern [[Siberia]], and [[Transbaikal]] Railways. The last was withdrawn from regular scheduled express passenger train service in 1974. All were staged in full working order and kept in reserve for times of extraordinary demand. At certain intervals, the locomotives were taken out from staging, steamed up and put to work to haul trains to test the condition of the locomotives. In the late 1980s, these strategic reserves of locomotives were disbanded and the Class P36 locomotives were distributed to museums and for preservation. Some that had not seen regular use for more than fifteen years and were in the worst mechanical condition, were scrapped. It was found that the roller bearings suffered most by standing unused. When the computerised new class numbers were introduced by the Russian Ministry of Railways, the Class P36 were designated Class 1000.0001 to 1000.0251. In the 1990s, after the collapse of the Soviet Union, a number were sold to private train operators. {{Citation needed|date=November 2012}}

===Spain===
The 242F class express passenger {{nowrap|4-8-4}} locomotives were designed by the [[Red Nacional de los Ferrocarriles Españoles]] (RENFE) in 1955 and were remarkably well-proportioned. Developed from a preceding {{nowrap|4-8-2}} Mountain type, they had improved steam passages and developed 30 to 40 per cent more power at medium cut-offs and high speed. Ten of these locomotives were built by {{lang|es|i=unset|La Maquinista Terrestre y Maritima SA}} in [[Barcelona]] to burn fuel oil. They had Witte type smoke deflectors and were fitted with a double [[Kylchap|KylChap]] (Kylälä-Chapelon) blast-pipe, a Worthington feedwater heater and a {{lang|es|Traitement Integral Armand}} (TIA) water-softening device. To increase the comfort of the locomotive crew, the cabs had wooden floors mounted on springs, and the seats of the driver and fireman were also sprung, a very welcome improvement for long runs on poor tracks. These locomotives were painted in a green livery when turned out from the builder's works at Barcelona and were consequently nicknamed {{lang|es|Los Verdes}} (The Greens). {{Citation needed|date=November 2012}}

[[File:Bf Madrid Delicias, 242 F 2009.jpg|thumb|left|RENFE 242F class]]
The 242F class was the fastest Spanish steam locomotive. When tested on the line from Barcelona to [[Tarragona]] across {{convert|10.4|mi|km|abbr=off}} of practically level and straight line between [[Vilanova i la Geltrú]] and Sant Vicent, a speed exceeding {{convert|84|mph|km/h|abbr=off}} was sustained twice, first with a train of 430 tons and then with a train of 480 tons. High-capacity tests took place between [[Madrid]] and [[Ávila, Spain|Ávila]] when a train weighing 426 tons, including a dynamometer car, was hauled at sustained speeds of {{convert|70.3|mph|km/h|abbr=off}} up a gradient of {{nowrap|0.35%}} (1 in 286), {{convert|57.2|mph|km/h|abbr=off}} up a gradient of {{nowrap|1.05%}} (1 in 95) and {{convert|39.1|mph|km/h|abbr=off}} up a gradient of {{nowrap|{{frac|2|1|4}}%}} (1 in 44.5). The gross horsepower figures recorded with the dynamometer car were 1790, 2350 and 2320 respectively, the calculated horsepower on the rail being 2600, 3400 and 3580. The latter output translates to about {{convert|4000|ihp|abbr=off}}.

With these locomotives, there was some concern about water supply. The capacity of the tender was limited at only {{convert|6200|impgal|L|abbr=off}} and, with few watering points in service, the full capacity of the locomotive was not always used for fear of running short of this essential commodity in the semi-arid Spanish landscape. For example, for the {{convert|163|km|mi|adj=mid|long|0|abbr=off}} stretch between [[Medina del Campo]] and [[Burgos]] that rises {{convert|131|m|ft|abbr=off}} with an uphill start, three intermediate stops, one slack and some shunting movements to couple extra coaches to the train, the amount of water consumed was about {{convert|7300|impgal|L|abbr=off}}.{{Citation needed|date=November 2012}}

All ten locomotives were allocated to the [[Miranda de Ebro]] shed to haul principal heavy express trains. In the 1960s, they were a familiar sight at the head of the premier express trains, but in 1971 they were transferred entirely to semi-fast passenger trains and even to the haulage of heavy seasonal fruit trains between [[Castejón, Navarre|Castejón]] and [[Alsasua – Altsasu|Alsasua]] from October to January. One locomotive, no. 242F.2009, is preserved at the [[Railway Museum (Madrid)|Madrid Railway Museum]].<ref>{{cite web | url=http://andrewstransport.smugmug.com/keyword/Madrid%20Railway%20Museum%20photos/i-gxNtzqr|website=Andrew Naylor's travel and transport photos|access-date=16 February 2016 | title = Madrid Railway Museum photos | last = Naylor | first = Andrew }}</ref>

===United Kingdom===
In 1938 [[William Stanier]] considered a [[4-6-4]] express passenger locomotive design,<ref>{{Cite book
  |title=Chronicles of Steam
  |last=Cox  |first=E.S.
  |year=1967
  |publisher=Ian Allan
}}</ref> together with a 4-8-4 version as a large [[mixed-traffic locomotive]]. War intervened and suspended development of express passenger locomotives, but the 4-8-4 design was re-examined in 1942 by [[Charles Fairburn|Fairburn]], the acting [[Chief Mechanical Engineer|CME]], as a possible post-war type for fast [[fitted freight]]s.<ref>{{Cite book
  |title=Locomotives That Never Were
  |last=Barnes  |first=Robin
  |publisher=Jane's
  |year=1985
  |isbn=0-7106-0326-6
  |chapter=35: 1942 LMS 4-8-4
  |pages=76–77
}}</ref>

While no steam locomotives were known to be this type, an experimental [[Diesel locomotive#Diesel–mechanical|diesel-mechanical]] locomotive, the [[British Rail 10100]], had this wheel arrangement, but it was scrapped after a gearbox failure caused a loss of interest in the project.

===United States===
[[File:Steam locomotive in Vancouver, Washington -a.jpg|thumb|Spokane, Portland and Seattle No.&nbsp;700]]
[[File:Women wipers of the Chicago and North Western Railroad.jpg|thumb|Women [[wiper (occupation)|wipers]] of the [[Chicago and North Western Railroad]] cleaning one of the {{nowrap|4-8-4}} "Northern" H-class steam locomotives, [[Clinton, Iowa]], 1943]]

The American {{nowrap|4-8-4}} was a heavy locomotive, with nearly all examples in the United States having axle loads of more than {{convert|30|ST}}. On railroads with rail of {{convert|130|to|133|lb/yd|kg/m}}, axle loads of more than {{convert|36|ST}} were permitted. Exceptionally heavy {{nowrap|4-8-4s}} were therefore introduced on the [[Atchison, Topeka and Santa Fe Railway|Atchison, Topeka and Santa Fe]] (Santa Fe), [[Chicago and North Western Transportation Company|Chicago and North Western]] (CNW), [[Chesapeake and Ohio Railway|Chesapeake and Ohio]] (C&O), [[Chicago, Milwaukee, St. Paul and Pacific Railroad|Milwaukee Road]] (MILW), Northern Pacific (NP), [[Norfolk and Western Railway|Norfolk and Western]] (N&W), [[Spokane, Portland and Seattle Railway|Spokane, Portland and Seattle]] (SP&S) and [[Western Maryland Railway|Western Maryland]] (WM) railroads. The [[Santa Fe Class 2900]] had the heaviest axle load of all at {{convert|38.75|ST}} as well as being the heaviest {{nowrap|4-8-4s}} ever built, weighing {{convert|974850|lb|abbr=on}} total. The lightest {{nowrap|4-8-4s}} in the United States were the six H-10 class locomotives of the [[Toledo, Peoria and Western Railway|Toledo, Peoria and Western]] (TPW), with an axle load of {{convert|23|ST}}.<ref>{{Cite web|url=https://steamlocomotive.com/locobase.php?country=USA&wheel=4-8-4&railroad=atsf|title=Atchison, Topeka & Santa Fe 4-8-4 Locomotives in the USA}}</ref><ref name="Northern Type TP&W">{{Cite web |url=http://www.steamlocomotive.com/northern//?page=tpw |title=Toledo, Peoria, & Western 4-8-4 "Northern" Type Locomotives |access-date=2012-11-17 |archive-url=https://web.archive.org/web/20121015081431/http://steamlocomotive.com/northern/?page=tpw |archive-date=2012-10-15 |url-status=dead }}</ref>

Some {{nowrap|4-8-4s}} were used on exceptionally long runs.
* The Santa Fe Heavy Mountains were rostered to haul the ''Chief'' and ''Fast Mail'' trains between [[La Junta, Colorado]], and [[Los Angeles]] across {{convert|1255|mi|km}}, and also handled the ''Grand Canyon Limited'' between Los Angeles and [[Wellington, Kansas]], across {{convert|1534|mi|km}}. From 1942, they ran through from Los Angeles to [[Kansas City metropolitan area|Kansas City]] via the [[Belen Cutoff]] and [[Amarillo, Texas]], a distance of {{convert|1789|mi|km}}, setting a new record for through steam locomotive rosters.<ref name="Vernon L 1967">Vernon L. Smith. ''The Case for the American Steam Locomotive''. Trains Magazine, August 1967</ref>
* The [[New York Central Niagara|Niagaras]] of the [[New York Central Railroad]] (NYC) also accomplished long runs on [[New York City|New York]] to [[Chicago]] passenger trains, including the ''Chicagoan'' and the ''Commodore Vanderbilt''.<ref name="Northern Type NYC">{{Cite web |url=http://www.steamlocomotive.com/northern//?page=nyc |title=New York Central 4-8-4 "Northern" Type Locomotives |access-date=2012-11-17 |archive-url=https://web.archive.org/web/20121015075551/http://steamlocomotive.com/northern/?page=nyc |archive-date=2012-10-15 |url-status=dead }}</ref>
* The Northern Pacific {{nowrap|4-8-4s}} hauled the ''North Coast Limited'' across {{convert|1008|mi|km}} from [[St. Paul, Minnesota]], to [[Livingston, Montana]].<ref name="Northern Type NP">{{Cite web |url=http://www.steamlocomotive.com/northern//?page=np |title=Northern Pacific 4-8-4 "Northern" Type Locomotives |access-date=2012-11-17 |archive-url=https://web.archive.org/web/20121015081506/http://steamlocomotive.com/northern/?page=np |archive-date=2012-10-15 |url-status=dead }}</ref>
* The [[Great Northern Railway (U.S.)|Great Northern]] [[Great Northern S-2|S-2 Class]] of {{nowrap|4-8-4s}} hauled the ''Empire Builder'' across {{convert|1306|mi|km}} from St. Paul, Minnesota, to [[Wenatchee, Washington]], and possibly as far west to [[Seattle]], a maximum distance of {{convert|1400|mi|km}}.<ref>{{Cite web|url=http://www.gngoat.org/baldwins_on_gn.htm|title = Baldwins on GN}}</ref>

Several of the earlier {{nowrap|4-8-4}} locomotive models were modified or rebuilt during their service lives.
* Santa Fe developed their {{nowrap|4-8-4s}} for years, and named the classes based on the number of the first locomotive in the class. The fourteen [[Santa Fe 3751|3751 class]] locomotives that were introduced in 1927 and 1928 were of conservative design, with {{convert|73|in|mm|-1|adj=mid|-diameter}} driving wheels and a boiler pressure of {{cvt|210|psi|kPa}}. In 1938, these locomotives were rebuilt with more modern features, including new {{convert|80|in|mm|-1|adj=mid|-diameter}} [[Boxpok]] driving wheels, wider steam passages to and from the cylinders, the boiler pressure raised to {{cvt|230|psi|kPa}} and roller bearings on all engine axles. This gave them a maximum drawbar power of {{convert|3600|hp|kW}} at {{cvt|50|mph|km/h}}. Engine No.&nbsp;3752 was equipped with Franklin rotary cam poppet valve gear and achieved the very low steam rate of 13.5&nbsp;lb per indicated [[horsepower-hour]] {{nowrap|(2.28 mg/J).}} These locomotives were permitted to run at {{cvt|90|mph|km/h}}, but they were alleged to have exceeded {{cvt|100|mph|km/h}} several times.<ref name="Vernon L 1967"/>
* The heavy Class H Northerns of the Chicago and Northwestern Railroad were rebuilt in 1940 with lightweight rods, Boxpok driving wheels and roller bearings on all axles, and the boiler pressure was raised from {{cvt|250|to|275|psi|kPa}}. Some years later, 24 of them underwent another rebuild which included new nickel-steel frames, new cylinders, pilot beams and air reservoirs, new fireboxes and other minor improvements. These were reclassified as Class H-1.<ref name="Northern Type CNW">{{Cite web |url=http://www.steamlocomotive.com/northern/?page=cnw |title=Chicago & North Western 4-8-4 "Northern" Type Locomotives |access-date=2012-11-17 |archive-url=https://web.archive.org/web/20121015075634/http://steamlocomotive.com/northern/?page=cnw |archive-date=2012-10-15 |url-status=dead }}</ref>
* The S-2 Class Northerns of the Great Northern Railway were rebuilt to have [[Timken Roller Bearing Company|Timken]] [[roller bearing]]s on every axle in 1945, replacing their original plain bearings. Vestibule cabs were added to engine 2577 in the early 1930s and engines 2582, 2586, 2587 and 2588 by the late 1940s.<ref>{{Cite web|url=http://www.greatnorthernempire.net/index2.htm?GNEGN_S2_Class.htm|title = Great Northern Empire - then and Now}}</ref><ref>{{Cite web|url=https://steamlocomotive.com/locobase.php?country=USA&wheel=4-8-4&railroad=gn|title = Great Northern 4-8-4 "Northern" Locomotives in the USA}}</ref>

Some Northern locomotives were also rebuilt from older engines. Between 1945 and 1947, the [[Reading Company|Reading Railroad]] rebuilt thirty of their heavy I-10 class [[2-8-0|{{nowrap|2-8-0}} Consolidations]] to booster-fitted {{nowrap|4-8-4}} Northern locomotives with {{convert|70|in|mm|-1|adj=mid|-diameter}} driving wheels. An additional ring was added at the smokebox end of the boiler, which increased the length of the boiler tubes from {{convert|13|ft|6|in|m}} to {{convert|20|ft|m}}, and a larger smokebox was installed which increased the distance between the tube plate and the chimney centre line from {{convert|34|to|111|in|m}}. Steam pressure was raised from {{cvt|220|to|240|psi|kPa}}. Four syphons were fitted, three in the firebox proper and one in the combustion chamber. A twelve-wheeled tender was attached, weighing 167 tons in working order, with a capacity of 23.5 tons of coal and {{convert|19000|USgal|L}} of water. A new cast-steel frame was used, with the cylinders cast integral and roller bearings on all axles. They were reclassified to T1 and numbered 2100 to 2129. Two of these locomotives, preserved for hauling special trains, were still in use in 1963.<ref name="Northern Type Reading">{{Cite web |url=http://www.steamlocomotive.com/northern/?page=pr |title=Philadelphia & Reading 4-8-4 "Northern" Type Locomotives |access-date=2012-11-17 |archive-url=https://web.archive.org/web/20151222121616/http://www.steamlocomotive.com/northern/?page=pr |archive-date=2015-12-22 |url-status=dead }}</ref>

[[File:4449idle.jpg|thumb|[[Southern Pacific class GS-4]]]]
The Northerns were workhorses that went without much public recognition, with a few exceptions. The [[Southern Pacific class GS-4|Class GS-4]] ''Golden State'' locomotives of [[Southern Pacific Transportation Company|Southern Pacific]] (SP), of which 36 were built by Lima Locomotive Works in 1941 and 1942, were semi-streamlined and were given a striking livery with a broad orange valence over the wheels below a narrow red band that came halfway up the cab windows. The locomotives headed the ''[[Coast Daylight (SP)|Coast Daylight]]'' train on the railroad's [[Coast Line (UP)|Coast Line]] between Los Angeles and [[San Francisco]]. The television program ''[[Adventures of Superman (TV series)|Adventures of Superman]]'' is introduced with a shot of an SP GS-4 as the narrator declares that [[Superman]] is "more powerful than a locomotive." One of them, [[Southern Pacific 4449]], has been restored and is in operating condition.<ref name="Northern Type SP">{{Cite web |url=http://www.steamlocomotive.com/northern/?page=sp |title=Southern Pacific 4-8-4 "Northern" Type Locomotives |access-date=2012-11-17 |archive-url=https://web.archive.org/web/20101230050634/http://www.steamlocomotive.com/northern/?page=sp |archive-date=2010-12-30 |url-status=dead }}</ref>

Even after the demise of steam, the Northern type has been in the spotlight of publicity and, along with [[Union Pacific 844]] of the [[Union Pacific FEF Series]] and [[Norfolk and Western 611]] of the [[Norfolk and Western J Class (1941)|Norfolk and Western Class J series]], among other Northerns, have been the favoured type to provide mainline excursions in the United States. The former is the only steam locomotive of a [[Class I railroad]] never to have been retired.<ref name=Americanrails>[http://www.american-rails.com/4-8-4.html American-Rails.com - The 4-8-4 Northern Type] (Accessed on 10 November 2016)</ref>

{{Clear}}