Athearn's Ready-to-Roll SD45T-2 in HO

The Cotton Belt didn't have a need for Tunnel Motors, but as a subsidiary of Southern Pacific, the railroad owned more than 100 SD45T-2s. ©2015 Ryan C Kunkle, licensed to, Inc.

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In the age of steam, there were many classic examples of locomotives that helped to define the character of a railroad: the New York Central's Hudsons, Union Pacific's Challengers. In the diesel era, unique motive power was less common, but examples could be still be found. Among those unique charismatic locomotives were the Southern Pacific's Tunnel Motors.

Both the SD40T-2 and SD45T-2 had a long history on the "Espee" and well beyond.

Although built for the railroad's mountain routes, the locomotives were known to wander well beyond the passes. Athearn's HO model combines the locomotives' unique lines and fine details with a smooth and quiet drive. These locomotives are a good value at $129.98 MSRP.


Prototype Background

EMD introduced the SD45T-2 just a few months after the SD45-2 in 1972. Southern Pacific had been a big fan of the original SD45, but faced issues with these and other diesels overheating in the many tunnels and snowsheds along their mountain routes. The solution was to move the air intakes in the radiator at the rear of the unit from the top to the bottom of the body. The look was as distinctive as the flared radiators of the original SD45s.

Internally, aside from the location of the radiator fans, the SD45T-2 had the same stats as the SD45-2. It generated 3600 horsepower from a 20 cylinder 645 engine. Dynamic brakes helped on the downhill grades.

The SD45T-2 was nearly 2 feet longer than the SD45-2. The extra frame length, needed for the larger radiator and the 20 cylinder engine block, also provided room for an even larger fuel tank. As if all of these spotting features weren't enough, the SP added their distinctive lighting packages to both ends of the unit.

The locomotives, originally built for the SP and subsidiary Cotton Belt, wandered far beyond just the mountains. Cotton Belt's terrain hardly required such units but the locomotives were used commonly on long-distance trains over the SP and, like the rest of the roster, were operated as a unified fleet. After the UP merger, many were sold to other railroads around the country. Many were rebuilt into SD40-2 specs and served in areas far beyond the mountain passes for which they were intended.


Paint and Details

Athearn has released the SD45T-2 several times in their Ready-to-Roll line. These models feature a respectable amount of separately applied detail parts, but not quite to the extent of the Genesis series. Depending on the age of the tooling, details on these models can vary. The SD45T-2 fares well.

Unlike many RTR models, the SD45T-2 features full walkway tread detail. Multiple antennae, piping, AC unit and bell on the roof really add to the detailed look - we see a lot more of the roof of our models than the underbody.

There are some details noticeably absent from this locomotive. Generally, these are of the common variety and not difficult to find or add on your own if you so desire.

The biggest voids are in the pilots. Air and MU hoses and coupler cut levers would go a long way to improving the look here. Holes for many of these parts are pre-drilled for you. That's a really nice touch and the models more than live up to the standards of the line, but it's worth noting that the last RTR locomotives I purchased, SW1500s, had all of the details this one lacks. For later eras, ditch lights could also be added. Also missing are windshield wipers. The model does have the distinctive "L" window cab. Some of these were replaced with more common 4-window cab fronts in later years.

Overall, the tooling on the body is very well done. door latches and hinges are molded crisply. The large radiator screens are molded solid and not see-through. The molding is nice and could be enhanced with a paint wash.

Aftermarket screen could be used to upgrade to a see-through mesh, but you'll see the gear tower and drive shaft inside. (There are articles on relocating these as well for a more prototypical look if you're willing to do the work.)

As usual, Athearn's paint and deco finish are second to none. Paint is evenly applied and the graphics are crisp and legible down to the finest print. This includes markings on the truck sideframes - a very nice detail!

Handrails are plastic, a fact often lamented on these models, but on the three samples I purchased everything was straight and well aligned. 



The locomotive runs smoothly and quietly at low speeds. These models will creep very nicely. It is everything you've come to expect from Athearn. A plug is provided for easily adding a DCC decoder. And this model has plenty of room to add a speaker if you want sound.

Athearn continues to use bulbs for lighting. These fit inside the housing somewhat loosely. It is especially noticeable on the lights between the numberboards. (These were Gyrolight warning lights - you could easily add the effect with most decoders.) If you've got the hood off to add a decoder, it is likely worth your time to replace the bulbs with LEDs as well. I know I'm not alone in thinking this change is the biggest thing Athearn could do to their models to make a major difference in overall quality.


Enhancements and Upgrades

By far the biggest thing "missing" from this locomotive is weathering. The SP was not well known for keeping their locomotives clean. The tunnel motors were leaders in grime - not surprising given the time they spent underground. It was not uncommon for units to be so dirty that none of the markings were legible.

There are many techniques you can use to weather a locomotive. While I usually argue for a "less-is-more" approach, if you're looking for a heavy weathering candidate, the T motors are a safe choice!

Adding the rest of the detail array to the pilots, cab, roof and underframe will also take this locomotive to another level.

The plastic knuckle couplers, while functional, could also be replaced with stronger metal versions for more reliability at the head of a long train.

Overall, for a street price around $100, Athearn has delivered another good value in a distinctive locomotive model. Athearn has already announced another run in different paint schemes and road numbers scheduled for delivery in June of next year. 


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