Bio Edit

The ATSF (Atchison, Topeka, And Santa Fe) SF30B is a type of four-axle, 12-cylinder, 3,000hp diesel locomotive built in 1987. The model is a unique rebuild of a U23B, and is essentially a B30-7 (or a B23-7 as a result of being de-rated to 2,300hp later in its life cycle); having been built to said specifications.

ATSF #6419 during its heyday.

Only one unit was built (ATSF #7200, later #6419), and was originally the testbed for a proposed rebuilding program which never green-lit. The unit remained in service until the BNSF merger in 1995-1996, and was renumbered BNSF #4276. It remained with BNSF until 2008, and was eventually sold to the Minnesota Commercial Railroad (MC; MNNR).

The sole unit is now currently in service with Minnesota Commercial as MNNR #42, and can be found among other older GE locomotive models owned by the railroad, as well as a lone ATSF SF30C survivor: the SF30B's essential six-axle (C-C) counter-part rebuild from a U36C.


In the 1980's, the Santa Fe opted to help recover from the severe losses plagued by the failed Southern Pacific-Santa Fe (SPSF) merger by saving what little monetary resources they had to slowly liquidate assets (locomotives, rollingstock, etc.) to further avoid bankruptcy. Although the railroad intended on acquiring more new locomotives to replace aging first and earlier second-generation diesels, the lack of funding proved otherwise. To resolve the issue, the railroad opted to begin rebuilding earlier four-axle GE diesels to help fuether reduce costs and essentially upgrade older models to becoming more up-to-date with the maintenance, horsepower, and operational standards at the time. As a result of the successes with the recent SF30C rebuilds, the railroad intended on rebuilding other Universal Series ("U-Boat") models like the U23B with updated specifications to meet said standards.

During the summer of 1987, ATSF #6332 (a U23B), was the first (and only) member of the proposed program, and was chosen as a result of being damaged from a wreck. Outshopped from the railroad's Cleburne, TX shops as ATSF #7200, the unit showcased a number of features unique to the locomotive. Among said features were an increase of a horsepower rating from 2,300 to 3,000 (thus, dubbing the name of the model) as a result of having updated 752 traction motors, an updated experimental variant of the 7FDL-12 prime-mover, and updated alternator. Other internal features included updated Dash 7 electronics, as well as the Sentry Series wheelslip control system found on Dash 8 and later production Dash 7 models. Drastic changes were made externally, however, from the hood to the rest of the entire carbody. To meet the cooling demands of the 7FDL-12F30UX, the carbody of the original U23B unit was outfitted with unique distinct air vents mounted on the rear of the long hood (rear nose face), further making the design far ahead of its time. The rear section of the carbody towards the long hood (behind the radiator section or rad-cab) was further given a beveled outcropping to accomodate cooling and general space for the prime-mover, while a Dash 7-style exhaust stack was placed in favor of noise reduction and emission requirements at the time. The frame however, was mostly reconditioned, as the fuel tank was enlarged and further wedged into it. The fuel tank on the otherhand, was completely refabricated and was reduced from 3,250 to 2,900 gallons, for the tank was split into two sections (the upper half being in a 45-degree fashion) to accomodate a rentention compartment. Apart from these changes were the unique enhancements given to the cab, for an air conditioner was implanted into the cab roof as opposed to having an AC or HVAC unit mounted on top or on the side of the locomotive in lieu of other existing models (though, BNSF eventually did such method by replacing the original conditioner for easier routine maintenance). The nose or front hood of the cab was completely overhauled as well, and given an SF30C-style appearance (hence, furthermore being the four-axle counter-part of said model). On another note, a flange lubricator tank was added behind the cab to reduce the wear of the wheels on rail curves.

Overall, the SF30B was proven to be a success, though by the time the program was proposed, the age of locomotive contracting was imminent, for railroads became more dependent on builders like Morrison-Knudsen (MK Rail) to rebuild or remanufacture existing locomotives rather than rebuilding them at their home shops. Furthermore, the ATSF eventually closed their Cleburne facility in favor of building more modern facilities as a result of BN's management during the BNSF merger. Prior to the merger, however, older locomotive models (including the otherwise short-lived C30-7) were traded-in for newer models like the B40-8 (57 C30-7's were traded in favor of receiving new B40-8's). Furthermore, four-axle models like the B40-8 replaced the need of rebuilding U23B's, for the ATSF fully recovered from their financial loses and began purchasing new locomotives to replace previous models between 1988 and 1996.

The sole SF30B unit originally was assigned to general revenue service until it was re-regulated to local and yard services. It now currently serves as part of the MNNR's main fleet, and can be seen anywhere on their system. 


Model SF30B
Production Dates 1987
Total Built 1
Top Speed 65 mph
Length 60' 2"
Width 10' x 3.0"
Height 15' x 6.5"
Wheel Arrangement B-B
Engine 7FDL-12F30UX (7FDL-12)
Horsepower 3,000 (later 2,300)
Alternator GTA11
Traction Motors 752E8
Weight x 1,000lbs. 277,000
Auxiliary Generator GY27
Gear Ratio 83:20
Fuel Capacity 2,900 gal.
Drivers 40"
Dynamic Brakes XR



Another known feature on the rear hood or long hood is the absence of grab irons for maintenance crews. Instead, they were replaced with a distinct ladder placed in between the beveled edges of the radiator section.

Despite having an entirely refabricated radiator section, the unit had the same amount of water used for engine cooling (350 gallons).

From the time of its construction, the unit retained its original AAR Type B trucks until 1993, when they were replaced in favor of high-speed GE FB2 trucks.

The FB2 trucks in which the sole SF30B retains were originally from ATSF #7401: one of three B39-8 testbeds scrapped between 1993-1994.

Like all locomotives at the time, ATSF #6419 gained ditchlights in 1996 as per FRA requirements in the 1990's.

The unit originally wore MNNR patchwork while dressed in its original ATSF "Yellowbonnet" livery until around 2012.

Sources Edit