The plain blue GECX Demonstrator engines continue to be used on BNSF coal trains as seen by the GECX 2041 lading a set of empties Northbound on the Joint Line.

A pair of the General Electric Tier IV Demonstrator engines lead a Southbound loaded coal train.

A pair of General Electric Demonstrator engines head South out of Denver down the Joint Line while testing in coal train service.

One of only 4 so far. This ES44A6 has Twin Turbo and new EGR system to meet the latest EPA Tier 4 emissions rating.