But while the more common 9-44CW offers 4,400 horsepower (3,300 kW), software in the 9-40CW's engine-governing unit restricts its power output to 4,000 horsepower (3,000 kW).

The design has since proven popular with North American railroads, although some railroads, such as CSX and Canadian Pacific, preferred its AC equivalent, the AC4400CW.

Because of more stringent emissions requirements that came into effect in the United States on January 1, 2005, the Dash 9-44CW has been replaced in production by the GE ES44DC.

They were originally ordered by Chicago & North Western Railway, Santa Fe, BNSF, CSX, Southern Pacific, Canadian National Railway, BC Rail, and Union Pacific Railroad.

The BNSF AC44C4M is an Ex-ATSF GE C44-9W rebuilt with AC traction motors and an A1A-A1A wheel arrangement.