The EMD (Electro Motive Division) SD80MAC is a type of 20-cylinder, six-axle, 5,000hp AC-traction diesel locomotive built from 1995 to 1996.
Conrail SD80MAC

A typical SD80MAC from its respective owner.

Only 30 were built specially for Conrail, and still exist today on Norfolk Southern (NS) and are used as spare units or helpers. They were once used by CSX, yet as a result of a recent trade agreement between the two railroads in exchange for ex-CR SD40-2's. As of early 2014, CSX has since scrapped one SD80MAC: #2594 (as a result of having a cracked frame from being involved in a wreck), with only 29 remaining. They are now owned and operated by NS.

They are considered to be somewhat rare, since they're only used on certain trains or as spare units, and can only be seen in certain areas on Norfolk Southern's railroad system (though, at times, one can be spotted elsewhere from the East Coast or the Midwest).

From 2011 to 2012, Vale Mining of Brazil acquired 7 mechanically-similar Tier 1-compliant, 20-710G3C-ES-equipped SD80ACe units, and are built for use on broad-gauge 5 ft 3 in (1,600 mm) trackage. Said units are currently available for export only, for they violate current EPA emission restrictions regarding new locomotives built beginning in 2014-2015.


AThe SD80MAC was one of the first and only domestic North American AC-traction diesel locomotives to have a 20-cylinder prime-mover (a 20-cylinder variant of the 16-710G3B), its own unique design (apart from its externally-similar counter-part introduced prior to the model), have digital high-tech microprocessor controls capable of inverting and converting DC-to-AC traction currents with its traction motors; updated self-steering axles on flexible trucks (being EMD's HTCR-II radial trucks), and to be the very first ever (and one of the only) AC-traction diesel locomotive models owned by Conrail. After the initial success of the SD70MAC in 1993 (one of the very first commercially successful, mass-produced models of single-engined AC-traction diesel locomotives produced for the North American locomotive market), EMD decided to avoid losing the competition entirely with GE's dominate and inreasingly-popular AC4400CW by introducing the SD90MAC and the externally-similar; yet much more successful and reliable (in terms of performance), SD80MAC. Thus, initiating the so-called "horsepower race" by beating GE with higher horsepower locomotives. Doing so, EMD opted to win over customers with sales exceeding expectations (they unfortunately fell short, however).

During the 1990's, the advent of AC-traction and the resultant increase in available adhesion and starting tractive effort touched off a new form of "horsepower race" as both builders (GE and EMD) sought to take advantage of the otherwise untapped  potential of AC systems capable of handling more horsepower than existing locomotives could deliver. EMD revived the 20-cylinder engine fad and took the lead ahead of the competition in 1995 with the introduction of the 5,000hp SD80MAC, which was originally proven that 2 units alone could outnumber a trio of GE AC4400CW's because of the advantage of having a higher horsepower rating of 5,000hp as opposed to just 4,400hp. Furthermore, the builder also stated that 3 SD70MAC's were once capable of replacing 5 DC-traction SD40-2's, furthermore boosting sales with the already-popular (yet not widespread) model already owned by Burlington Northern, who began receiving the last of the 350+ SD70MAC's from an order originally placed in 1993. After the initial success of the otherwise unique and revolutionary SD80MAC's early run, Conrail eventually followed suit and acquired 14 SD70MAC units to accompany their existing SD80MAC fleet and were assembled at the railroad's Juniata Shops between March and May of 1998. The SD80MAC's were typically assigned and used on Conrail's long and heavy coal trains through their steep, winding, high mountain routes throughout the Northeastern United States (though, since the split of Conrail by CSX and NS in 1999, they have since found their way through various different locations across the East Coast and the rest of the United States). During the Conrail Split of 1999, CSX acquired 12, while NS acquired the 18 remaining units despite having less than 5 years in service from their original owner.

The EMD SD80MAC was successful, yet didn't receive many orders because it was more expensive to maintain and build as of a result of its more advanced and otherwise confusing control schemes, had a less horsepower rating than its more popular and favorable 6,000hp counter-part (aside from its rival: the AC6000CW), and was ultimately unpopular, for railroads preferred having more cost-effective 4,400hp to 6,000hp AC-traction diesel locomotive models as opposed to having only 5,000hp; aside from the AC4400CW (the AC6000CW's counter-part) being a more affordable choice in contrast to the 4,000hp SD70MAC and the more expensive and complicated 5,000hp SD80MAC.

Conrail was the only customer to officially order the SD80MAC, yet the Chicago And Northwestern (CNW) and Canadian Pacific (CP) originally intended on ordering such units of the model. CNW originally opted to order 15 units to assist their existing AC4400CW fleet and further replace their existing SD60 units on coal trains along the Powder River Basin in Wyoming. But because of the UP's acquisition of the CNW in 1995 and the demonstrations of SD90MAC's on CP being more successful, the orders were ultimately cancelled, and Conrail remained the only customer to fulfill their purchase after receiving 3 seperate orders of 30 units total.

Spotting FeaturesEdit

The SD80MAC shouldn't be confused for the externally-similar SD90MAC, for the simple fact that UP and CP are the current owners of the  SD90MAC (aside from CEFX and CITX owning fleets of units leased to shortlines like the SLRG and INRD), while NS currently owns all SD80MAC units aqcuired from Conrail during the split of 1999, and a further 11 acquired from an auction made by CSX 15 years later in 2014.

It should also be noted that the dynamic brake grid located on the rear of the locomotive (on the far end of the long hood) is noticeably different in comparison to that of an SD90MAC.


Model SD80MAC
Production Dates 1995-1996
Total Built 30
Length 80' 2"
Wheel Arrangement C-C
Engine 20-710G3B-ES
Horsepower 5,000
Alternator TA22/CA8
Traction Motors 1TB2830
Weight x 1,000lbs. 420,000


The first two units built (EMDX 8000-8001) were assembled at EMD's London, Ontario facility, while the others were assembled at Conrail's Juniata, Pennsylvania shops. Like the SD45 (and subsequent models like the F45), the SD80MAC is one of the only models produced by EMD to feature or include a 20-cylinder engine. Most of the employees of Conrail originally weren't quite sure how to distinguish or even operate the SD80MAC because of it being completely different from their existing diesels. Thus, special tutorials were often given to help them avoid such issues (as seen in the video source).

Most railfans and crews originally were also puzzled by the way the SD80MAC looked, and thought it was originally an SD90MAC, as well as it being DC-powered rather than AC. To help solve the confusion, special distinct decals with "Radial-AC" slogans placed under the numbers helped identify the units better.

Like the SD90MAC, SD70MAC, and SD60MAC, the SD80MAC is often nicknamed "Mac" by most railfans, as well as being pronounced as SD80 "Mac". They were also known by railfans as the "Middle Mac": having 5,000hp in-between the SD70MAC having 4,000hp and the SD90MAC having 6,000hp.

Conrail's fleet of EMD SD80MAC's (aside from their fleet of SD70MAC's) were also painted in an exclusive scheme to distinguish them from other units.

They are often considered to be Conrail's "Cadillacs" because of them being unique, and that they were one of the last types of locomotive purchased and delivered to the railroad.

CSX designates the SD80MAC as simply the "SD80AC" because of it being a unique locomotive on their roster: not having any other model built within the "80" series besides the recent SD80ACe and the SD89MAC prototype.

One CSX SD80MAC humorously fell into the turntable well at the CSX Cumberland Shops facility due to slipping on sand while the brakes were released during inspection.

The last Conrail-painted units were repainted back in 2009. Since then, Conrail-painted SD80MAC's no longer exist.

Once CSX finished repainting their fleet of SD80MAC's, they were eventually renumbered from their original "800 series" number fleet before eventually renumbering them again to the "4500" series to make room for new GEVO units on their roster.

As of early 2012, the SD89MAC prototype was developed into a new type of EMD diesel locomotive; the EMD SD80ACe, which is practically a combination of the original SD80MAC, the SD89MAC, and the SD70ACe. It is currently in production for export in Brazil, yet EMD has yet to demonstrate the SD80ACe for North American Class 1 railroads.

CSX #4590 (formally #800) was painted with exclusive "Spirit of Benning" lettering as being part of the "Spirit Of" or "Spirit" units. As of 2015, it is now NS #7217, and is currently wearing the railroad's "Horsehead" or "Thoroughbred black" livery.

Ironically, NS left the original "Radial-AC" decals from Conrail, while CSX left their original marker lights; which were once commonly used from Conrail. As of now, none of the units retain their original marker lights.

CSX originally repainted their first half of SD80MAC's with their YN2 scheme, but once their YN3 scheme was introduced in early 2002, they eventually repainted all of their units into said scheme.

All, but one of the original 5 SD80MAC units (with one unit; EMDX #8001 not receiving a full livery) were originally painted red with white lettering when they were EMD demonstrators before eventually being purchased by Conrail.

Because of the recent acquisitions of former UP SD9043MAC's, NS has supposedly intended on rebuilding their fleet of former Conrail SD80MAC's by converting them into what are essentially SD70ACe's (by replacing the prime-mover and updating the software and controls). Said units will essentially be dubbed as SD70ACe's and built to Tier 3 SD70ACe specifications, but will retain their respective original bodies. In other words, NS has opted to rebuild all of the 29 remaining SD80MAC units to be compatible with their existing SD70ACe units by rebuilding them into "clone" SD70ACe units.



Conrail SD80MAC Pt1 of 5

Conrail SD80MAC Pt1 of 5

A video series (part 1 shown) documentary explaining the basics of an SD80MAC.