As of January 2005, the SD90MAC is no longer in production due to the Environmental Protection Agency's Tier 2 locomotive emission regulations, although EMD had planned to be able to get the H-engine approved at some later date.
However, China recently announced an order for 300 JT56ACe locomotives, which also use the H-Engine as its prime mover.
A portion of the locomotives will be assembled in kit form by China's own Dalian Locomotive Works.
These units were reportedly capable of meeting the EPA's strict regulations and began delivery in the latter half of 2007.

Due to reliability issues, FMG units 910 to 917 are stored and deemed not be used.
They were purchased to be used as "slave" units, and they were more offline than they were in use.
FMG is looking to fit 910-917 to the same specifications as 901-909.
916 is currently in the shops.

On 1 August 2008 Union Pacific Railroad announced that it would be retiring 21 of the SD90MAC locomotives.
Common parts will be used to maintain the railroad's 710-engined SD90MAC fleet.
The 265H prime mover will be cut up or exported.
The only part that is non-reusable will be the frame.
These units, in the 8900 series will be removed from storage in Denver, and be sent to East St. Louis, Ill., in small batches to be dismantled.
As of 2019, Union Pacific still operates some of the remaining SD9043MACs, which sport new numbers and UP wings on the cab.

Canadian Pacific's SD90MAC-H locomotives 9300-9303 (listed as SD90MAC6000s) were up for tendered sale in 2009.
The bidding ended 31 March 2010.
While they were originally thought to be shipped overseas, they were eventually moved to Quebec for scrapping.

Canadian Pacific's SD90MAC locomotives, numbered in the 9100-9160 series had been in long term storage in Winnipeg, Manitoba for much of the 2010-decade.
With three units, the 9129, 9133 and 9138 being scrapped in November 2012 due to errors in preparing them for long term storage.
The entire fleet had been put up for sale in November 2012 and again in January 2013 with no offers being made.
These units remained stored until the Winter of 2018 when at first 30, then all 58 remaining units entered a rebuild program to be converted into SD70ACUs.

In September 2014, Norfolk Southern purchased 100 4300 hp SD9043MACs from Union Pacific with the intent to rebuild them into SD70ACUs at the Juniata Shops.
The last 4 SD90MACs were taken delivery to Norfolk Southern on October 3, 2015 running parallel to Western Ave in Chicago IL.

On 26 June 2018 it was announced that CP had contacted Progress Rail (corporate parent to EMD) to rebuild 30 of their SD90MAC fleet into SD70ACUs, much like the Norfolk Southern had previously done with a second-hand SD90MAC fleet.
In 2019, an additional 30 units were added to the order for a total of 60 SD70ACU rebuilds, with 28 coming from the remainder of Canadian Pacific's SD90MAC fleet and the other two purchased from Union Pacific's SD90MAC fleet.

In 2015 Cummins rebuilt a single SD90MAC with its QSK95 engine, designed to meet Tier 4 emissions standards.
Sygnet Rail Technologies and Brookville Equipment Corporation performed the conversion.
The rebuild was designated HTL4200AC.
The locomotive, numbered CECX No.
1919, had been Union Pacific No.
8559.
As of January 2005, the SD90MAC is no longer in production due to the Environmental Protection Agency's Tier 2 locomotive emission regulations, although EMD had planned to be able to get the H-engine approved at some later date. However, China recently announced an order for 300 JT56ACe locomotives, which also use the H-Engine as its prime mover. A portion of the locomotives will be assembled in kit form by China's own Dalian Locomotive Works. These units were reportedly capable of meeting the EPA's strict regulations and began delivery in the latter half of 2007.
Due to reliability issues, FMG units 910 to 917 are stored and deemed not be used. They were purchased to be used as "slave" units, and they were more offline than they were in use. FMG is looking to fit 910-917 to the same specifications as 901-909. 916 is currently in the shops.
On 1 August 2008 Union Pacific Railroad announced that it would be retiring 21 of the SD90MAC locomotives. Common parts will be used to maintain the railroad's 710-engined SD90MAC fleet. The 265H prime mover will be cut up or exported. The only part that is non-reusable will be the frame. These units, in the 8900 series will be removed from storage in Denver, and be sent to East St. Louis, Ill., in small batches to be dismantled. As of 2019, Union Pacific still operates some of the remaining SD9043MACs, which sport new numbers and UP wings on the cab.
Canadian Pacific's SD90MAC-H locomotives 9300-9303 (listed as SD90MAC6000s) were up for tendered sale in 2009. The bidding ended 31 March 2010. While they were originally thought to be shipped overseas, they were eventually moved to Quebec for scrapping.
Canadian Pacific's SD90MAC locomotives, numbered in the 9100-9160 series had been in long term storage in Winnipeg, Manitoba for much of the 2010-decade. With three units, the 9129, 9133 and 9138 being scrapped in November 2012 due to errors in preparing them for long term storage. The entire fleet had been put up for sale in November 2012 and again in January 2013 with no offers being made. These units remained stored until the Winter of 2018 when at first 30, then all 58 remaining units entered a rebuild program to be converted into SD70ACUs.
In September 2014, Norfolk Southern purchased 100 4300 hp SD9043MACs from Union Pacific with the intent to rebuild them into SD70ACUs at the Juniata Shops. The last 4 SD90MACs were taken delivery to Norfolk Southern on October 3, 2015 running parallel to Western Ave in Chicago IL.
On 26 June 2018 it was announced that CP had contacted Progress Rail (corporate parent to EMD) to rebuild 30 of their SD90MAC fleet into SD70ACUs, much like the Norfolk Southern had previously done with a second-hand SD90MAC fleet. In 2019, an additional 30 units were added to the order for a total of 60 SD70ACU rebuilds, with 28 coming from the remainder of Canadian Pacific's SD90MAC fleet and the other two purchased from Union Pacific's SD90MAC fleet.
In 2015 Cummins rebuilt a single SD90MAC with its QSK95 engine, designed to meet Tier 4 emissions standards. Sygnet Rail Technologies and Brookville Equipment Corporation performed the conversion. The rebuild was designated HTL4200AC. The locomotive, numbered CECX No. 1919, had been Union Pacific No. 8559.
EMD SD90MAC