Intermountain (China) EMD Tunnel Motors

Introduced: 2003 (SD40T-2) and 2005 (SD45T-2)

Both of these locos share the exact same chassis / mechanism, so I'm going to save myself a bit of time and cover them both here. The design is very much similar to the Atlas SD50/60 mechanism. And although not exactly the same, they do appear to share many of the same internal components (motor, etc). Just speculating here, but I assume this means that they were made at the same Chinese factory that Atlas uses.

The mechanism sports all the features one normally associates with "modern" diesel models - IE, DCC-Ready / split-frame / all-metal chassis, 5-pole / skew-wound / "slow speed" motor, dual flywheels, low-friction drive, bi-directional LED lighting, all-wheel drive and pickup (no traction tires), blackened / low-profile wheels, shell-mounted Accumate couplers, all-plastic gearing, etc.

The good news is that performance on these models is perfect in every way - smooth, quiet, flawless pickup and throttle response, exceptional pulling power, etc. Further good news is that the paint and detailing are excellent (I particularly like the see-through fan screens).

On the down side, I've had just a ton of trouble with the shells on these things. The press-fit handrails are extremely flimsy and tend to pop out and fall off if you look at them wrong. And in a similar vein, the shell is comprised of a lot of interconnected pieces that just aren't connected together very well. The cab and nose sections are particularly prone to getting misaligned (or simply falling off) if you're not extremely careful about how you handle them. It looks to me like all the various pieces are actually held together with glue (and poorly applied glue at that). Worse still, some of these are delivered from the factory absolutely slathered in some sort of oily lubricant (and which may account for the aforementioned glue issues).

I'm also told that there a few "rivet counting" type issues to worry about (for those that worry about such things).

- Missing gap between the dustbin hatch and exhaust hatch
- Misplaced beads on the blower ducts
- Fans visible through the radiator grills (they shouldn't be)

So, ultimately a couple of very nice looking and nice running models that, unfortunately, have a few "fit and finish" issues. Consequently, no "A" rating here.

Decoder installation is fairly simple, and the procedure is exactly the same as installing a decoder in an Atlas diesel (IE, you have to de-screw the two halves of the frame in order to install the decoder). I did notice that my Digitrax decoder board is a bit thicker than the stock lightboard, meaning I had to widen the little slots in the frame enough to accommodate said wider PCB (just insert a thin, flat screwdriver and pry the slots open a little wider). Be sure to save the little shroud from the stock lightboard for the rear LED on your decoder (otherwise it will be visible through the sides of the shell). Also, be sure to slide the decoder as far towards the back of the chassis as it will go or there won't be enough room for the plastic clip that goes around the forward LED. Lastly, keep an eye on where the motor contacts are touching the decoder board. Sometimes they may require a little bit of judicious bending in order to get them to properly touch said contacts.

Shell removal is blessedly simple - just take hold of the fuel tank with one hand and the shell with the other. Then, just sort of wiggle it up and off. But be careful - as mentioned above, the whole assembly is going to fall apart in your hands if you manhandle the thing.

Grade: B (because of the shell issues)

SD40T-2 reviewed: 11/04 Model Railroader ("A handsome N scale SD40T-2 tunnel motor locomotive is now available from InterMountain. It features a detailed plastic body, six-wheel trucks, and a smooth-running dual-flywheel mechanism that can be easily adapted for DCC. This well-proportioned model... is offered in several versions that match the variations in the prototype orders... Our samples came assembled and ready-to-run with Micro-Trains couplers. Clear plastic window glazing is fitted into the cab with appropriate window wipers. Our samples were smoothly painted with sharply printed lettering... The mechanism follows the popular split-frame design used in most N scale diesel models... A PC board mounted on top of the chassis holds the model's LED headlights and control circuitry. It can be easily replaced with drop-in decoders... Our sample performed well. Though they seemed a little stiff at first, the drive mechanism ran smoothly after running for a short period of time. All three started at virtually the same speed and voltage, and I could get them to run steadily at 4.8 scale mph. The engine's drawbar pull is equivalent o 19 cars... They operate well on 9" radius curves... The couplers are mounted at the correct height in boxes attached with small Phillips screws. I'm happy to see these excellent SD40T-2's with railroad-specific details appearing in N scale. Their different profiles will certainly add realism to any train heading into the picturesque Front Range of the Rockies or California's rugged Sierra Nevada mountains. D&RGW, CB, S&W, SP, UP, Undec. $119.95")