Rivet Counter HO Scale GE DASH 8-40C, CSX/YN2/Blue Cab Roof

By the early 1970s, locomotive reliability became the focal point of many railroad operating departments. To satisfy customer demands, EMD introduced its Dash-2 line of models in 1972. This upgraded series proved popular on models already well into production, such as the 2,000-horsepower GP38-2 and 3,000-horsepower SD40-2, which dominated locomotive sales through the mid-seventies.

During this time, GE marketed its own line of improvements under the XR (Xtra Reliability) series. GE would retain the original model designation, U (for universal series), but not for long. In 1976, GE dropped the U series naming convention. Incorporating a wide range of improvements, the 3,000-horsepower, six-axle U30C became the C30-7 model, the 2300-horsepower, four-axle U23B became the B23-7, etc.

The popular C30-7 model dominated the first two years of C-Boat production. In 1977, the first 3,600-horsepower version was assembled - a test bed unit (numbered 505) built for GE's engineering department. Two years later, in 1979, the first production C36-7 was built for Nacionales de México (N de M), and in March 1981, the first C36-7s for US roads were built. Between 1981 and 1985, 169 C36s were constructed, and with each new order, various external and internal changes were introduced as GE revamped and upgraded its product line to compete with the new EMD 50-series locomotives.

Starting in 1985, in order to counter EMD’s new SD60, GE featured an uprated prime mover which now produces 3,750 horsepower in the C36-7s.

In addition to the horsepower change, the last two years of C36 production brought mechanical and carbody changes that eventually would become standard Dash 8 features. The most prominent change was the mounting of the dynamic brake grids in a boxy structure behind the cab.

With these changes in the B36/C36 line, GE built several units that were test beds for new features, including microprocessor controls. The first of these was GE 606, a B36-8 built in 1982. The following year, a six-axle version designed as a C36-8 model (numbered 607) rolled off the plant floor. Computerized controls allowed the horsepower rating of the units to be uprated, and in 1984, 607 was "rebuilt" and redesignated as a C39-8.

In January 1984, three 12-cylinder, 3,150-horsepower B32-8s were built while a single B39-8 and two C39-8s (powered by a 16-cylinder engine rated at 3,900 horsepower) were assembled. These demonstrators were supposed to be dispersed to various railroads across the country, but GE decided to confine the units to specific railroads where they could be more closely watched. 

These initial demonstrator sets were followed in September by 10 six-axle C32-8s (powered by a 12-cylinder, 3,150-horsepower engine) lettered for Conrail (numbered 6610-6619). Of these four models, only the C39-8 produced any orders. In October and November 1984, Norfolk Southern purchased 12 units.

In 1986, GE built 50 C39-8s for Norfolk Southern and 25 for Conrail. The following year, 67 B39-8E (E for enhanced) units were built for its own locomotive leasing subsidiary, LMX, and 40 B39-8Es for Southern Pacific. Norfolk Southern continued to buy six-axle C39-8s (now designated C39-8E), adding 25 units, bringing its total C39 fleet to 138 units. In addition to building enhanced versions of its B39-8 and C39-8 models, a new locomotive design was headed down the assembly line in late 1987 – the first Dash 8-40C.

While these new units built for Union Pacific in November 1987 were heralded by GE as being the latest in locomotive technology, they were, in fact, refined versions of the B39-8E and C39-8E. Externally resembling the E-series introduced a year earlier, these models featured internal improvements based on tried and proven technology. 

Microprocessor controls, first introduced and tested on GE's test bed B36-8, 606, in 1982, are the heart and soul of the Dash 8 models. By constantly evaluating and adjusting the auxiliary systems, the microprocessor can increase the horsepower available for traction.

Before the introduction of microprocessor controls, computers became an integral part of wheel-slip control. Wheel slip is controlled on the Dash 8s by GE's Microsentry system. Although a more refined version is applied to the Dash 8, the Sentry wheel-slip system was introduced by GE in 1971. 

Beginning with the introduction of the Dash 7 locomotives in 1977, fuel economy has been a major selling point of the GE models. Between 1977 and 1984, fuel consumption was improved by 16 percent with the Dash 7 series. The Dash 8 line has improved the fuel consumption by another 4 percent.

While EMD has progressed through three engine model changes – from 567, to 645, and the current 710 series power plant – GE has remained with the FDL designation first introduced to the domestic market on the U25B model. But today's FDL engine features engineering improvements that extend the life of various engine components.

The Dash 8-40C model is the culmination of a major evolution that began with GE 505 in 1978, although many components of the Dash 8 were first seen on the U25B in the early 1960s.

GE's Dash 8 - C Series, Dieselization Enters the Third Generation, originally published by Withers