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NORFOLK SOUTHERN
DIESEL LOCOMOTIVE ROSTER

EMD/NS SD70ACU Nos. 7229-7337

103 Units Active

7 Additional units undergoing rebuilding (see bottom of roster)

Active Roster

General Info

NS Model Designation = SD70ACU
Horsepower = 4,500 (see note below)
Fuel Tank Capacity = 4,700 gallons (see note below)
Maximum Weight = See note below
Dynamic Braking = Yes
Control = Single
Cab Signals = Yes
LSL (Locomotive Speed Limiter) = Yes
Air Conditioning = Yes

Units are powered by an EMD 16-cylinder 710G3C-ES engine.

Units that have received a full engine overhaul meet Tier 1+ emission standards, while units that
have not yet received a full engine overhaul meet Tier 0+ emission standards. While all of the rebuilds are
being upgraded to 4,500 traction horsepower, the Tier 0+ units generally only make 4,300-4,400 horsepower.
Those units that have been overhauled and meet Tier 1+ emission standards are:
7233, 7235, 7242, 7243, 7250, 7253, 7254, 7258, 7269, 7278, 7291,
7293, 7296, 7298, 7305, 7308, 7313, 7319, 7323, 7329, 7333, 7337

As originally built by EMD, the SD90MAC had a fuel tank capacity of 5,700 gallons. While owned by Union Pacific,
the units started developing cracks in the frames around the fuel tank mounts.  UP worked with EMD to solve the
frame cracking problem by adding additional mounting brackets between the frame and fuel tank. In addition, the fuel
filler pipes were modified to only allow a maximum of 4,700 gallons of fuel to be added. All of the former UP units had
this modification when they were delivered to NS. NS did this modification to the former CIT units during rebuilding.

As originally built by EMD, the SD90MAC had a maximum weight of 415,000 pounds. After being rebuilt in
the SD70ACU program, the maximum weight initially increased to 420,000 pounds due to the additional weight
of the new widenose and cab.  Starting with the 35th SD70ACU rebuild, NS began adding additional weight to
each end of the units to increase the maximum weight to 432,000 pounds. The first 34 units will also have the
additional weight added as shop time permits. Those units that have received the additional weight are:
7230, 7231, 7232, 7233, 7234, 7236, 7237, 7239, 7240, 7241, 7242, 7243, 7244, 7246, 7247, 7249, 7251,
7253, 7254, 7255, 7257, 7259, 7260, 7266, 7269, 7271, 7272, 7274, 7275, 7277, 7278, 7280, 7281, 7284,
7285, 7287, 7288, 7289, 7291, 7295, 7296, 7300, 7301, 7302, 7303, 7304, 7306, 7307, 7308, 7310, 7311,
7312, 7313, 7314, 7315, 7316, 7317, 7318, 7321, 7322, 7323, 7325, 7326, 7328, 7329, 7333, 7337

Original cab and electrical cabinet were replaced with new EMD SD70ACe style isolated cab,
AAR-style control stand, and electrical cabinet with Mitsubishi electronics.

Units retain their original TA22 main alternator and 1TB2830 traction motors.

Equipped CCB II computer controlled braking system.

Equipped with GE Ultra Cab II Cab Signaling and LSL (Locomotive Speed Limiter).

All units are equipped with NS LEADER/PTC (Positive Train Control) system.

Equipped for use in DPU (Distributed Power Unit) operation.

Equipped with Automatic Engine Stop/Start.

New electric parking brake added with brake wheel on the left side of the long hood.

Ditch lights added to the rear during rebuilding.

Numbering Notes

NS 7229 was added to the SD90MAC numbering in December 2014 when the former UP 3481/8015
was sent as a trade-in to EMD in place of former UP 3666/8196, which was to have become NS 7319. Since
the former UP 3481/8015 was from the first UP SD90MAC order, NS chose to number it as 7229.

NS SD90MAC 7329 was originally supposed to have been former UP 8274, but UP retained that unit
and sent UP 8247 to EMD in its place. The unit was delivered to NS as UP 8247 and was not renumbered or
placed in service as an NS unit prior to entering the NS SD70ACU capital rebuild program. It was
numbered 7319 to fill the open 7319 number slot to make the 7229-7328 series a solid group of 100 units.