Union Pacific Railroad

General Notes:

1. UP 3600-3637 were built with 59:18 gear ratio (90 mph); changed to 62:15 (65 mph) in 1976.
2. UP 3638-3649 (12 units) were assigned to Utah and Colorado to California unit coal train service for Kaiser Steel, beginning in December 1968, in joint operation with D&RGW, which assigned six of its new SD45s to the same pool. The Kaiser trains operated until about 1979.
3. In late 1969 to late 1972, UP 3600-3636 (19 even numbered units) were equipped as Radio Control System (RCS) control units.
4. In late 1969 to late 1972, UP 3601-3635 (18 odd numbered units) were equipped as Radio Control System (RCS) remote units.
5. UP 3600-3649 were renumbered to UP 50, 1-49 between September 1978 and March 1979; UP 3600 was the first unit completed, renumbered to UP 50 on 22 September 1978.
6. UP 3600-3621 were built on EMD order number 7975.
7. UP 3622 was built on EMD order number 7107.
8. UP 3623 was built on EMD order number 7108.
9. UP 3624-3649 were built on EMD order number 7077.

General Notes:

1. Original total of 38 MKT units; 36 units went to UP at merger; MKT retired two units (MKT 613 and 628) prior to the merger.
2. UP 3844 was built as MKT 637 by EMD in May 1985 using the frame and trucks from MKT 613 (EMD 786228-3 in September 1979) and power equipment and portions of the carbody from MKT 628 (EMD 786228-10, July 1980); both units had been wrecked on 17 March 1983 at Smith, Texas, and were retired in July 1984; frame and trucks from MKT 613 sent to EMD, along with components from MKT 628; frame of MKT 628 scrapped by MKT at Parsons, Kansas, during July 1984.
3. UP 3831 (ex MKT 623) was the first unit in this group to be repainted to Union Pacific, completed on 8 December 1988; UP 3843 (ex MKT 636) was the last, completed on 13 November 1990.
4. UP 3836-3841 were purchased by UP on 1 March 1997 after expiration of original MKT capital lease on 1 February 1997.

Notes:

1. Nine unretired units (UP 3809, 3811, 3818, 3822, 3824, 3828, 3833, 3836, 3838) were renumbered to the new 3100-3522 series to clear this 3800 series for use by new SD70M units, numbered from 3779.
2. UP 3829 (ex MKT 621) was retired on 29 November 2001; reinstated as Peak Power UP 7909 on 26 January 2004; renumbered to UP 3613 (2nd) on 29 May 2007 to clear the UP 7909 number for use by a new GE C45AC-CTE in 2008.
3. UP 3831 (ex MKT 623) was converted to remote control for yard switch service and renumbered to UPY 3831 on 3 June 2004.
4. UP 3840 (ex MKT 633) was wrecked (head-on collision) on 17 October 1993 at Machovec, Texas, on ATSF; scrapped at the wreck site; sold to ATSF as part of settlement; carcass of unit sold for scrap by ATSF to Erman-Howell, Turner, Kansas. (spelling changed from Makovic, per email from Russ Strodtz dated March 24, 2003; previous spelling was based on UP accident reports, actual spelling taken from BNSF records)
5. UP 3844 (ex MKT 637) was returned to its owner/lessor in January 1996 upon expiration of its 10-year lease; sold to National Railway Equipment, Silvis, Illinois; sold to IC in September 1996 and renumbered IC 6072.

General Notes:

1. Total of 74 MP units went to UP at merger, numbered as MP 6000-6073.
2. MP 6000-6073 were built using the same specifications as Burlington Northern SD40-2s and assigned to unit coal train pool service on BN and D&RGW; MP used SD40-2C as the model designation for these units.
3. MP 6000-6019 were equipped with twin Mars lights, mounted on their low noses; some modified by removing the lights following wreck repair.
4. MP 6000-6019 were built as the first MP 3216-3235 series; renumbered to MP 6000 series in May 1978.
5. UP 3900-3974 were originally assigned UP 4222-4296 series, later changed to UP 3900 series.
6. UP 3901 had North Little Rock style lettering.
7. UP 3902 (as MP 6002) was the first MP yellow unit painted at North Little Rock, Arkansas, in mid-August 1984.
8. UP 3953 (ex MP 6053) was the first unit in this group to be repainted to Union Pacific, completed on 28 January 1986; UP 3971 (ex MP 6071) was the last, completed on 5 June 1992.
9. Total of 19 units were retired but still on property and were renumbered in February 2003 to the temporary WP reporting mark to clear the 3900 series for use by new SD70Ms (delivered beginning in March 2003).
10. Total of 21 units were still in service and were renumbered in November 2002 through February 2003 to the new 3100 series numbers to clear the 3900 series for use by new SD70Ms (delivered beginning in March 2003).
11. Total of seven units were still in service and were renumbered to the 9800/9900 series numbers in January through March 2003 to clear the 3900 series for use by new SD70Ms (delivered beginning in March 2003).
12. Individual unit histories:

Notes:

1. UP 3900-3904 were retired on 1 February 1994 upon expiration of lease and returned to owner/lessor, GATX; in national lease service as GATX 900-904.
2. UP 3908 (as MP 6008) was wrecked on 6 August 1987 at Tacoma, Washington, and was renumbered to UP 3908 in May 1988 while undergoing wreck repairs at VMV Enterprises, Paducah. Ky.
3. UP 3956 was sold to Helm Financial in (?), and as of 2004, was in national lease service as HLCX 6234. (Extra 2200 South, Issue 126, page 13)
4. UP 3960 was retired on 27 February 2001, but was still on UP property with the planned delivery of new SD70Ms in the 3900 series; renumbered to temporary WP number, as WP 3960 on 13 February 2003 to clear the UP 3960 number; renumbered again to UP 7897 on 23 December 2003; retired again as UP 7897 on 28 July 2004.

General Notes:

1. UP 4141 was renumbered to UP 3778 on 15 October 2005 to clear the 4141 number for use by a new SD70ACE, painted in a white and blue scheme that commemorates President George H. W. Bush, the 41st president.

General Notes:

1. All units are equipped with larger radiators in a flared carbody to accommodate separate radiator cores for diesel engine jacket water and for aftercoolers.
2. All units are painted with UP's"Building America" slogan and U.S. flag decal, in memory of 11 September 2001.
3. The original unit that was to enter service as UP 3971 was instead, delivered as UP 4841 (2nd) to replace UP 4841 (1st) following that unit's return in late November 2002 to GMLG-London to repair a freeze-damaged engine block.
4. Order numbers (frame numbers) for these units are different from the builder numbers in that they include the build location, such as L for London and M for Mexico; UP 3779-3822 are order (frame) number L-20036559; UP 3823-3873 are order (frame) number M-20036559.

Notes:

1. UP 3833 was wrecked on 23 April 2009 at Oakwood, Texas; also wrecked and retired were UP 4479 and UP 9556.
2. UP 3971 is actually a renumbered and frame-restamped UP 4841 which was returned to EMD after freeze damage occurred to the engine block during delivery. To replace the UP 4841 as quickly as possible EMD selected another SD70M that had just been completed. This replacement SD70M was intended to be UP 3971, serial 20006271A-20, but when EMD numbered it as UP 4841 they restamped its frame as 20006271A-5. The original UP 4841 (1st) was repaired by EMD, renumbered to 3971 and restamped as 20006271A-20. Upon repair, UP 4841 (1st) was renumbered to UP 3971 and delivered to UP in late March 2003.

General Notes:

1. Total of 25 SP units went to UP at merger, numbered SP 9800-9824.
2. Assigned UP 9900-9924 in September 1997, no units renumbered; assigned UP 3974-3984, and 3986-3999 in December 1999, leaving the UP 3985 number slot for use by UP's 4-6-6-4 Challenger steam locomotive.