Editing GE Evolution Series (section)

=== ES44AC (2003–present) ===
[[File:CN 2869 EF-644p parked along the Riverwalk Trail in Quesnel, BC (DSCF5166).jpg|thumb|[[Canadian National Railway|CN]] ES44AC No. 2869]]

The '''ES44AC''' (Evolution Series, 4,400&nbsp;hp, AC traction) replaced the [[GE AC4400CW|AC4400CW]] model in the General Electric catalogue. These locomotives have been ordered by every Class I railroad in North America: [[Union Pacific Railroad]] (who refers to these locomotives as the ''C45ACCTE''), [[BNSF Railway]], [[CSX Transportation]], [[Norfolk Southern Railway]], [[Ferromex]], [[CPKC Railway]], and [[Canadian National Railway]]. 

Union Pacific also bought the heavy ballasted variation of this model, the ES44AH, and refers to it as the C45AH. UP also uses this designation to refer to their ET44AH units.

CSX Transportation has bought these locomotives and they were always heavy ballasted, so they called these the '''ES44AH'''. The first set was 700-999, which was built from 2007-2011. Beginning 2023, CSX has repainted and renumbered the 3000 series locomotives to heritage units. The first heritage, 1827, was painted into Baltimore & Ohio and renumbered from 3059 on May 11, 2023.

BNSF Railway purchased 25 ES44AC locomotives in 2023, and they are all classified as '''ES44ACH.''' They were built between August and September of 2023 and were built concurrently with the '''ET44ACH'''. The numbers were 3282-3306, which officially ended the production of the '''ES44C4''' in 2020. These units are Tier 4 credit units. In 2024, BNSF has bought 25 more ES44ACH locomotives, which are numbered from 3307-3331. These locomotives weigh 436,320 lbs.