While originally designed to house a 6000hp engine, technical difficulties resulted in many SD90MACís being equipped with a 4300hp engine instead, which gave them the designation SD90/43MAC. The locomotives were reliable and effective enough with these engines that though the option to upgrade was given, most locomotives kept the as-shipped 4300hp AC traction engine.
The San Luis & Rio Grande Railroad (SLRG) runs west from a connection with the Union Pacific railroad at Walsenburg, CO, over the Sangre de Cristo Mountains at La Veta Pass and into the fertile valley of the San Luis and Rio Grande Rivers. In addition to operating excursion trains through the La Veta pass, the SLRG hauls grain and various minerals, utilizing the colossal pulling power of the SD90 to great effect.
- Locomotive feature directional Golden White LED headlights and ditch lights.
- Powerful five pole motor with brass flywheels and all-wheel electrical pickup from scale 42" blackened metal wheels.
- Comes with a number of consumer applied detail parts such as individually molded windshield wipers, MU hoses, and grab irons.
- "Drop-in" DCC friendly with a NMRA standard 8-pin plug for easy DCC upgrading.