The NRE 3GS21C is a low-emissions diesel genset locomotive built by National Railway Equipment (NRE). It is powered by three Cummins QSK19C I6 engines with each one developing and creating a total power output of . Instead of a single prime mover, the NRE genset locomotive has three engines that each can be turned off or on as power is needed reducing overall diesel emissions and improving fuel efficiency. At least 27 3GS21C genset locomotives have been produced to date at NRE's Mount Vernon shops in Southern Illinois. The main difference between this and the NRE 3GS21B is that these units are on C-C (six wheel) trucks and the others are on B-B (four wheel) trucks.

Original buyers Railroad Quantity Road numbers NotesBNSF Railway 16 1300-1316Burlington Northern Santa Fe Roster information on BNSF - Motive Power. Revised: 11 Dec. 2016. ex-ATSF EMD SD40, SD45 and SD45-2Dallas, Garland & Northeastern Railroad 3 2000-2002Dallas Garland & Northeastern Roster information on DGNO Present & Past Power. Revised: 6 Feb. 2016. ex-UP EMD SD24BNorfolk Southern 1 38503GS21CDB NS 3850 NS Norfolk Southern Roster Locomotive. Built in 2008. Ex-Norfolk Southern 3188 EMD SD40NREC 3GS21C NS 3188 Norfolk Southern. Pacific Harbor Line 2 80-81Pacific Harbor Line Locomotives (past & present) Revised: 15 Nov. 2015. The first 3GS21C built, in Jan. 2008PHL 3GS21C PHL 80 Pacific Harbor Line. Indiana Harbor Belt Railroad 4 2160-2163All Time - Indiana Harbor Belt Railroad Diesel Locomotive Roster NRE 3GS21C "gensets" Revised: Jan. 2013. 2012CSX Transportation 1 1600CSX Motive Power * * * Yard Power * * * Updated: 11 Dec. 2016 Total

Flexibility Because the engines are modular, flexibility is obtained:

If one engine fails, the others can continue at reduced power. If a lower axle load is needed, one engine can be omitted. When reduced power is needed, one or more of the engines can be turned off, saving fuel and wear and tear. The QSK19C engine is common to the four variants of the NRE 3GS21C locomotive. The QSK19C engine is widely used for non-railway applications, and spare parts are readily available.

See also NRE 3GS21B

References