GE Universal Series
The GE Universal Series is a series of diesel locomotives intended for the export market introduced by General Electric in early 1956. General Electric had previously partnered with Alco, producing locomotives for export using Alco's 244 engine, and provided electrical parts for Alco's domestic production. However, with the advent of the Universal Series, GE ended its partnership with Alco and entered the export locomotive market on its own.
The export-oriented Universal Series should not be confused with the "U-Boats" for the North American market, which began with the U25B. Universal Series locomotives can be identified by the lack of battery boxes usually found under North American locomotives' cabins
Naming convention
The designations of the Universal series describe the locomotive model in compact form: U for Universal, followed by the engine's nominal horsepower rating in hundreds, and finally the number of axles; B = B-B ; C = C-C. An 'M' indicated a modified version of the base model. Along with their development, the same numbers were often reused by different locomotive models. Even the same designation could be shared with domestic locomotives. For example, both the U18C and U20C model numbers refer to different locomotives offered at different dates with different engines ; and the export U30C model shared the same model number with the US U30C, but had a 12-cylinder, rather than a 16-cylinder engine.Engines
The initial models of the Universal Series used Caterpillar 375, Caterpillar 397, Cooper-Bessemer FWB-6L, Cooper-Bessemer FVBL-8 and FVBL-12. Later models substituted higher-power Caterpillar engines for the smaller locomotives or GE's own 7FDL8 and 7FDL12 engines for the larger ones. Unlike EMD, GE never had a 16-cylinder engined export locomotive model in the Universal series.| Engine | Number of locomotives built using engine |
| Cooper-Bessemer FWB-6L | 40 |
| CB FBVL-8 | 333 |
| CB FBVL-12 | 191 |
| Caterpillar D379 | 342 |
| Cat D398 | 736 |
| General Electric 7FDL8 | 885 |
| GE 7FDL12 | 1510 |
| Others | 54 |
Specifications
Based on the March 1989 GE Locomotives catalog, the following models were offered at the following specifications.| Model | Engine | Horsepower | Wheel arrangement | Length | Height | Nominal weight | Tractive effort |
| U10B | Caterpillar 3512 | 800 hp | B-B | ||||
| U18C | 7FDL8 | 1800 hp | C-C | ||||
| U20C | 7FDL12 | 2000 hp | C-C | ||||
| U22C UM22C | 7FDL12 | 2150 hp | C-C | ||||
| U26C | 7FDL12 | 2600 hp | C-C | ||||
| U30C | 7FDL12 | 3000 hp | C-C |
Models
Upon introduction in 1956, nine locomotive models were offered, as follows:| Model | Engine | Horsepower | Wheel arrangement | Type | Photo |
| U4B | CAT 375 | 340 | B-B | End-cab switcher | Not built |
| U6B | CAT 397 | 640 | B-B | End-cab switcher | |
| U8B | CAT D398 | 900&1000 | B-B | Road switcher | |
| U9B | CB FWB-6L | 900 | B-B | Road switcher | |
| U9C | CB FWB-6L | 900 | C-C | Road switcher | |
| U12B | CB FVBL-8 | 1200 | B-B | Road switcher | |
| U12C | CB FVBL-8 | 1200 | C-C | Road switcher | |
| U18B | CB FVBL-12 | 1800 | B-B | Road switcher | Not built |
| U18C | CB FVBL-12 | 1800 | C-C | Road switcher | |
| UD18B | CB FVBL-12 | 1800 | B-B | Road switcher |
The evolution of Universal Series locomotives is complex due to the frequent model name changes and the reusing of the same model names for different locomotives. One method to understand the growth and development of the Universal Series is to divide the nine original models into three groups: 1) small locomotives, 2) intermediate powered locomotives, and 3) high powered locomotives.
Small Locomotives
In this table, and the following two tables, asterisks indicate repeated model numbersBetween the initial models and the first update, the Caterpillar 375 and 397 engines were replaced with 379 and 398, respectively.
The UM6B was a narrow-gauge variant of the U6B, built for South African Railways.
The 6-cylinder U9B and U9C models were an evolutionary dead end, and no uprated versions were produced.
Intermediate Powered Locomotives (8-cylinder)
Between the first and second updates, the Cooper-Bessemer engine was replaced with 7FDL8 engine. The body style was also changed with a low short hood and Hi-Ad trucks replacing the high short hood and outside-equalized trucks.A variation of the U18C was the U18A1A, built for the Indonesian railway. These locomotives had the same C-C trucks but one fewer traction motor in each truck, and downrated to 1650 horsepower. Most of these locomotives have been rebuilt to U18C standards.
High Powered Locomotives (12-cylinder)
As with the intermediate powered locomotives, the Cooper-Bessemer engine was also replaced with 7FDL12 engine.The differently-rated U22C, U26C and U30C models were offered at the same time.
The U18C and the earlier U20C model had a variant with an additional non-powered leading axle in each truck, resulting in a lower axle loading and a 1C-C1 wheel arrangement. These locomotives were only purchased by the South African Railways.
No U18B was produced, and the few UD18 locomotives built were exported to Mexico.
Universal Series statistics
4,091 Universal Series locomotives were built between 1956 and 2001, consisting of the following models:| Model | Number constructed by model |
| U20C and U20C1 | 1,000 |
| U10B | 510 |
| U18C, U18C1 and U18A1A | 420 |
| U26C | 392 |
| U15C and U15A1A | 322 |
| U6B and UM6B | 156 |
| U5B | 139 |
| SG10 and SG15 | 126 |
| U12C | 123 |
| U8B | 122 |
| U13C | 109 |
| U12B | 97 |
| U22C and UM22C | 93 |
| UM10B and UM10A1A | 91 |
| UM12C | 80 |
| U13B | 74 |
| U11B | 62 |
| U17C | 58 |
| U30C | 52 |
| Other models | 65 |
South Africa has the largest number of Universal Series locomotives, with 1040 locomotives, followed by Brazil with 864 locomotives. Other countries owning more than 100 locomotives are Argentina, Colombia, Indonesia, Mozambique and The Philippines.
The majority of the locomotives were built in the General Electric plant in Erie, Pennsylvania, however, licensees such as Dorbyl, GE do Brasil and Babcock y Wilcox constructed significant numbers of locomotives. Other licensees building smaller numbers of locomotives included Krupp, GE Lokindo, GE Montreal, Goninan and Nippon Sharyo.
| Builder | Number constructed by builder |
| General Electric | 2,478 |
| Dorbyl | 709 |
| GE do Brasil | 544 |
| Babcock y Wilcox | 259 |
| Others | 101 |
Production peaked in the 1970s, with almost 2,000 locomotives built during this time.
| Decade | Number constructed per decade |
| 1956-1960 | 527 |
| 1961-1970 | 1,125 |
| 1971-1980 | 1,926 |
| 1981-1990 | 369 |
| 1991-2001 | 144 |
The majority operated on meter gauge and 3 ft 6 in gauge railways.
| Gauge | Number constructed by track gauge |
| and | 243 |
| and | 1,056 |
| ' | 2,101 |
| ' | 296 |
| 191 | |
| and | 204 |
Further developments
Parallel to the developments of domestic US locomotives, 'Dash-7' versions of Universal Series locomotives were produced, among others, C18-7i, C20-7i and C24-7i, C22-7i, and C30-7i. The ADTranz 'Blue Tiger' was a high-powered locomotive designed for the export market. During its short production run, three variations were produced: Germany, Malaysia, and Pakistan.As of 2022, no Universal Series locomotive remained in the Wabtec catalog. However, the C30ACi and C21EMP-C25EMP series are the direct descendants of the U18C lineage; while the C20ACi is the descendant of the U12C series. Examples of the modern-day versions of Universal Series locomotives are Chilean C23EM, Indonesian C20EMP and CM20EMP, and Pakistani C20EMP locomotives.