Athearn HO SD40T-2

Athearn’s HO scale Electro-Motive Division SD40T-2, first released in 1984, has received an extensive makeover with railroad-specific details, see-through air intakes and dynamic brake fans, and Celcon handrails. The Ready-to-Roll direct-current model has a Quick Plug for conversion to Digital Command Control (DCC).

Prototype history. When Southern Pacific commissioned EMD to build the SD40T-2 in the mid-1970s, the locomotive manufacturer went back to the tunnel motor design it used on the SD45T-2s in February 1972. Tunnel motors have lowered air intakes to draw cool, clean air into the high-mount radiators, which helps prevent overheating in tunnels and snowsheds.

Though the SD40T-2 has the same boxy long hood as its bigger cousin, the SD45T-2, the easiest way to tell the two apart is to count the radiator-fan doors above the intake screens. The SD40T-2 has two, the SD45T-2 has three.

The SD40T-2 was produced from June 1974 until July 1980. During that time, 312 of the 3,000-hp units were manufactured. Three railroads, SP (229), Denver & Rio Grande Western (73), and SP-subsidiary St. Louis Southwestern (10), acquired the locomotives. Union Pacific inherited the SD40T-2s fol-lowing its acquisitions of SP and D&RGW. Some of the units have been spun off and can be found in lease service and on railroads such as the Indiana & Ohio; New York, Susquehanna & Western; Ohio Central; and Wheeling & Lake Erie, among others.

Noticeable improvements. Athearn’s new SD40T-2 features a higher level of detail than those originally released more than 20 years ago. Our sample, decorated for Denver & Rio Grande Western, has Celcon handrails, wire grab irons, a Positive Traction Control box between the electrical cabinet air-filter box and blower housing, and an 88″ nose. Athearn offers the model with 81″ and 123″ noses to match other prototypes. The longer nose housed Locotrol and other communication equipment so the locomotive could be used remotely as a mid-train helper. The see-through air intakes are great, even though the worm gear assembly is visible inside the hood.

The m.u. hoses, rear sand-filler hatch, and uncoupling levers are omitted. These details can be added using aftermarket parts. The front and rear pilots have factory-drilled holes for easier installation of the hoses and levers.

The paint is smooth and evenly applied, and the orange lettering and striping is opaque. Small labels, such as fuel fill and emergency fuel cut-off, are legible under magnification.

One feature that stands out on the Rio Grande model is the screw-mounted, injection-molded plastic, 4,000-gallon fuel tank with filler neck, sight gauge, and flush-mount gauge detail. Modeler-installed tank details, such as breather and sump drain pipes, are included. Two small illustrations, which show where to put the fuel tank details, are printed on the instruction sheet with the exploded-view diagram of the model.

The detailed HT-C trucks are accurate for the D&RGW model, as are the 40″-diameter blackened metal wheels. One error, a carryover from the original model, is the short wheelbase. It should be 45′-5″, not 44′-5″. In HO scale the difference hardly noticeable.

Performance. The model’s starting voltage is 2.6 volts with a slow speed of 7.6 scale mph. The engine lurched slightly at slow speeds, but most Athearn units smooth out once they’ve run for a few hours. The tunnel motor’s top speed is 84.7 scale mph. With a drawbar pull of 3.2 ounces, the SD40T-2 is capable of pulling 45 HO freight cars on straight-and-level track.

Unlike the original model, this direct-current tunnel motor has a Quick Plug for installing a DCC decoder. Though the single incandescent bulb in the cab has been replaced with directional microbulb headlights, the intensity of the lights is still dependent on track voltage like before.

Though the SD40T-2 will operate on 18″ radius curves without difficulty, the overhang isn’t very realistic. Broader curves (22″ or larger) are better for the six-axle locomotive.

Athearn’s SD40T-2 is another example of the firm’s commitment to making its existing products even better. With railroad-specific details, see-through parts, and an upgraded mechanism, the new Athearn tunnel motor is a step above its predecessors.

Athearn HO SD40T-2
Price: $99.98

Manufacturer
Athearn Trains
1550 Glenn Curtiss St.
Carson, CA 90746
www.athearn.com

Description: Plastic-and-metal ready-to-run locomotive

Road names: Denver & Rio Grande Western; New York, Susquehanna & Western; Southern Pacific; Union Pacific; and undecorated (with 81″, 88″, or 123″ nose)

HO SD40T-2 features
Blackened RP-25 contour wheelsets, correctly gauged
Celcon handrails
Digital Command Control decoder Quick Plug
Directional headlights
Drawbar pull: 3.2 ounces
McHenry magnetic knuckle couplers (at correct height)
Minimum radius: 18″
Positionable cab windows
Railroad-specific details
See-through air intake grills
Separately applied wire grab irons
Weight: 18 ounces