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Conrail SD80MAC 4100.jpg
Type and origin
Power type Diesel-electric
Builder General Motors Electro-Motive Division (EMD)
Model SD80MAC, SD80ACe
Build date 1995–1996 (SD80MAC), 2011– (SD80ACe)
Total produced 30 + 7
AAR wheel arr. C-C
Gauge 4 ft 8 12 in (1,435 mm)
Wheel diameter 45 in (1,143 mm)
Length 80 ft 2 in (24.43 m)(80MAC)
76 ft 6 in (23.32 m)(80ACe)
Height 15 ft 5 in (4.70 m)(80MAC)
15 ft 10 in (4.83 m)(80ACe)
Locomotive weight 420,000 lb (191,000 kg)(80MAC)
432,500 lb (196,000 kg)(80ACe)
Fuel capacity 5,800 US gal (22,000 l; 4,800 imp gal)(80MAC)
4,900 US gal (19,000 l; 4,100 imp gal)(80ACe)
Prime mover EMD 20-710G3B-ES(80MAC)
EMD 20-710G3C-ES(80ACe)
Cylinders V20
Transmission diesel electric
Performance figures
Maximum speed 75 mph (121 km/h)
Power output 5,000 hp (3.7 MW)
Tractive effort Starting (80MAC): 185,000 lbf (822.92 kN)
Continuous (80MAC): 147,000 lbf (653.89 kN)
Starting (80ACe): 191,000 lbf (849.61 kN)
Operator(s) Conrail, Norfolk Southern, CSX
Class NS 7200–7228, Vale 101-107
Disposition most still in service as of 2012

The SD80MAC is a 5,000 horsepower (3.7 MW) C-C diesel-electric locomotive. The model uses a 20 cylinder version of EMD's 710G prime mover, and is the first diesel locomotive to use a 20-cylinder engine since EMD's SD45 and SD45-2. It introduced a wide radiator housing similar to GE Transportation locomotives and the placement of dynamic brakes at the rear of the locomotive, which is a quieter location, features that were incorporated into the SD90MAC and SD70ACe models. Key spotting difference between the SD80MAC and SD90MAC include no external rear sandbox on SD90MAC, rear number boards, and the placement of the front numberboards (above the cab windows on SD80MAC, on the nose on most SD90MACs). It also has recessed red marker lights in the nose, an identifying feature unique to Conrail locomotives, although Norfolk Southern (NS) has removed the lights on most of their engines.

All 30 units built were delivered to Conrail, and 28 production units were completed, tested, and painted at the former Pennsylvania Railroad shops in Altoona, Pennsylvania. The other two units rostered by Conrail were EMD demonstrator units that were purchased outright[1] Many consider the SD80MAC to be the last new locomotive Conrail purchased as a truly independent railroad. In the split of Conrail, Norfolk Southern received 17 units (numbered 7200–7216) while CSX got 13 (800–812, being renumbered to 4590–4602). The former Conrail units were the first AC traction locomotives owned by Norfolk Southern, with the railroad not ordering more until late 2008 with an order of General Electric's ES44AC.

Chicago and North Western Railway ordered 15, along with Canadian Pacific, but the orders were canceled or changed. Conrail ordered more, but its new owners changed the order to SD70s and SD70MACs, all of which would be built at Altoona.

In 2009, NS 7205, the final SD80MAC in Conrail's scheme, (formerly CR 4109) was repainted to Norfolk Southern's scheme. No SD80MACs remain in Conrail's color scheme.

In late 2011, Vale Mining of Brazil has ordered a set of 7 updated locomotives designated as the SD80ACe model. These locomotives feature Tier 1 compliant 20-710G3C engines. The design is currently for export only, and these specific locomotives will run on Vale Mining's 5 ft 3 in (1,600 mm) broad gauge trackage.

Disposition of the original SD80MACs[edit]

In January 2014, CSX 4594, formerly CSX 804, and built as CR 4110, was scrapped after being used as a parts donor following a derailment in early 2009. This makes it the first (and only) SD80MAC to be scrapped.

In late 2014, Norfolk Southern announced that they had reached an agreement with CSX Transportation to trade 23 EMD SD40-2 units (NS 3425-3447) for CSX's remaining 12 SD80MACs, leaving NS as the model's sole operator. Norfolk Southern plans to use the 12 SD80s to supplement its existing fleet in unit train coal service. The trade was finalized in March, 2015 and NS instead traded 12 SD40-2 units (NS 3425-3427, 3430, 3432-3433, 3438-3440, 3443, 3446-3447) for the 12 SD80MACs owned by CSX. Norfolk Southern has numbered these units 7217-7228, which aligns these units with the existing SD80MACs on the NS system (numbered 7200-7216).

As of April 2015, Norfolk Southern has taken delivery of the 12 SD80MACs from CSX. Four of the units acquired from CSX have been repainted into Norfolk Southern's standard 'Horse Head' paint scheme. The remaining 9 units from CSX still wear patched paint. Excluding unit 7225, all former CSX units remain in storage pending mechanical repairs and/or repainting.[2]

While Norfolk Southern removed the marker lights from the 17 SD80MACs they acquired during the Conrail split, CSX did not remove them from their 12 units. Norfolk Southern has not yet removed the red marker lights from these units; the lights can still be observed on the cab noses of the 12 former CSX SD80MACs. It is expected that the marker lights will eventually be removed, as it has been a standard practice for NS to remove all marker lights on former Conrail units.

All SD80MACs will eventually enter an extensive rebuild program along with the 100 former UP SD90MACs NS has acquired from EMD.[3] The program will upgrade the electronic components of these locomotives to SD70ACe specifications and may include newer crash-rated cabs similar to those found on current SD70ACe units. The rebuild program is scheduled to begin in the summer of 2015 and will see the SD80MACs cycled through after the completion of work on the SD90MACs. The SD80MAC rebuilds will retain their 20 cylinder EMD 20-710G3B prime mover.

80MAC technical details[edit]

Prime Mover:

  • Electro-Motive Diesel V-20 710G3B-ES
  • Displacement: 14,200 cubic inches (233 L)
  • Idle: 200 rpm
  • Full Speed: 904 rpm
  • Lube Oil Capacity: 510 US gal (1,900 l; 420 imp gal)
  • Cooling Water Capacity: 342 US gal (1,290 l; 285 imp gal)
  • Fuel Capacity: 5,800 US gal (22,000 l; 4,800 imp gal)

Main Alternator:

  • Electro-Motive Diesel TA22-CA8A
  • Maximum Voltage: 2600 V DC
  • Maximum Current: 8100 A

Traction motors:

  • 6 Siemens 1TB2830 AC motors mounted 3 each on 2 HTCR-2 Radial Self Steering trucks.
  • Rated Output: 638 kW (856 hp)
  • Gearing: 83:16
  • Wheel Size: 45 in (1,143 mm)
  • Max Revolutions: 3,435 rpm
  • Starting torque: 16,300 N·m (12,000 lbf·ft)
  • Continuous torque: 12,900 N·m (9,500 lbf·ft)
  • Maximum voltage: 2,183 V


  • Maximum Speed: 75 mph (121 km/h)
  • Starting Tractive Effort: 185,000 lbf (820 kN)
  • Continuous Tractive Effort: 147,000 lbf (650 kN)
  • Braking Effort: 96,000 lbf (430 kN))
  • Weight: 210 short tons (187.5 long tons; 190.5 t); 420,000 lb (190,500 kg))