After the success of the AC4400CW, GE decided to expand their success of AC-traction diesel locomotives by developing an even greater advantage by having a single-engined type of diesel locomotive be capable of providing high amounts of horsepower (from up to 5,500hp or more), in turn reducing the need for multiple units on a single train. Hence, the development of the AC6000CW during 1997 (with the prototype developed the previous year): a revolutionary type of single-engined, or standard diesel locomotive capable of generating such high amounts horsepower and be AC-traction powered with having such motors provided to do so (besides the SD90MAC); as well as having more advanced microprocessor controls and twin turbochargers (as opposed to having an optional special engine or motor). The HDL prime mover was co-designed by Duetz of Germany and GE.
Though capable of having such features, the AC6000CW (like its rival) wasn't fully developed. The 6,000hp 7HDL-16 wasn't completed in-time during the unit's introduction, and customers (with Union Pacific being the first) were purchasing such units with 4,300hp to 4,400hp as opposed to having their exclusive 6,000hp engine. Hence, the 6,000hp engine was offered; but unavailable during the early years, and was simply replaced with a standard 7FDL-16 type of 4,400hp engine with built-in turbocharger (though, capable of having to to close to 5,000hp). Thus, the early AC6000CW units being dubbed "convertibles": a type or model of diesel locomotive capable of being fitted with different parts or engines able to easily be modified; hence, making the engine's horsepower rating editable by adding an additional turbocharger and/or changing the output through the advanced microprocessor controls.
They were originally were built to compete with the EMD SD90MAC shortly after its introduction in 1995, and thus the AC6000CW dominated over the SD90MAC in sales, popularity, and suffered little to no issues compared to the SD90MAC when they were first produced (after the exclusive engine was completed). Though, their production was short-lived; however, due to being non-energy efficient (having a large fuel-consumption) and they eventually had numerous "teething" problems with the prime mover or engine like with the SD90MAC (and it's Phase 2 "H" counter-part), furthermore the locomotive's prime mover could not be produced after 2004, becuase of heavy pollution and having such high fuel consumption. The unit could not be made Tier 2 compliant.
Many are still in service, but most no longer use their original 6,000hp engine, and are used as spare units.
Union Pacific and CSX were the only US railroads to purchase the AC6000CW. Outside of the US, BHP Billiton used these locomotives for hauling iron ore. They some have been repowered with GEVO16 prine movers.
A all of CSX's AC6000CW's have been repowered with GEVO16 prime movers. They also feature upgraded controls and electrical. These units are back out on the mainline leading priority trains.
The AC6000CW is commonly confused with the GE AC4400CW and other wide-cab GE locomotives.The main way of distinguishing them from other GE units, is by the distinct extended radiator fin, which also has a hump; aside from one side of the frame being slightly elevated where the air tanks are located (with the airtanks being different as well.)
- The AC6000CW is also known simply as the "AC60CW", "CW60AC", or the "C60AC".
- They were also built to compete with the less-successful EMD SD90MAC. GE succeeded, yet 80% of GE AC6000CWs have been converted and downgraded since around 2004.
- AC6000CW's are basically AC4400CW's, only with a much higher horsepower rating and different components.
- Few AC6000CW's were exported to Australia to work the immense ore trains of the Pilbara, and have upgraded 6,250hp engines and different controls.
- The most notable difference between the AC6000CW and AC4400CW is that they have a much larger radiator section for successful cooling of the larger engine.
- To celebrate having some of the first AC-powered, 6,000 hp diesel locomotives, CSX painted their AC6000CWs with commemorative yellow lettering on their YN2 scheme, as well as having "Diversity In Motion" and "Spirit Of" units.
- Some have been downgraded to having 4500, 4400, and 4450 horsepower from CSX and UP due to the US EPA's "tier 2" policy.
- Southern Pacific had three units on order, but were never delivered and were delivered to CSX. They were to be numbered 600-602.
- CSX AC6000CWs 600-602 were derated to 4400 horse power by removing their 6000 horse power 7HDL-16 prime movers with 4400 horse power 7FDL-16 prime movers and were reclassified as AC4460CWs.
- CSX is still repainting their units in YN3 scheme.
- When GE promoted the AC6000CW, the prototype and several demonstrators were painted green as part of GE's "Green Machine" campaign. Yet, the AC6000CW ironically wasn't even energy-efficient.
- AC6000CW's were commonly used during their early years of introduction as helper units assigned to long coal trains on the now-closed Tennessee Pass railroad line in Colorado. Thus, the trains they hauled and assisted were very similar to the BHP ore trains.
- The AC6000CW also holds the record for hauling one of the longest trains in the world for BHP, as stated in the Guinness Book of World Records.
- The downgraded versions of the AC6000CW are often known as the "AC4460CW", "AC4300CW", or the "AC43W".
- CSX #666; an AC6000CW, was infamously nicknamed "the devil train" or "the devils numbers" by railfans and employees. Hence, a small stencil located on a side of the cab before eventually being repainted into YN3 as opposed to its original YN2 scheme.
- GE recently upgraded several of CSX's AC6000CW units to have GEVO microprocessor controls and features to be compatable with their fleets of ES44AC (designated "ES44AH") units.