Union Pacific Railroad

General Notes:

1. Original total of 279 SP units, numbered SP 100-378; 277 units went to UP at merger; SP retired two units (SP 145 and 224) prior to the UP merger; SP 145 and 224 were wrecked on 21 February 1996 at Pando, Colorado, on Tennessee Pass; both units were scrapped at the wreck site; the cab from SP 145, along with a set of trucks and both fuel tanks, was salvaged and retained at the former SP Burnham Shops in Denver, Colorado; the cab from SP 145 was used in August 1997 to repair wreck-damaged C&NW 8671, which became UP 9775.
2. SP 100-271 assigned UP 6380-6549 in September 1997, three units (UP 6500, 6527, 6534) renumbered; assigned UP 6148-6317 in December 1999 (UP 6500, 6527, 6534 assigned UP 6421-6423 to clear the 6500 series numbers for use by new C44ACs in January to June 2000).
3. SP 272-378 assigned UP 6888-6994 in September 1997, one unit (UP 6895) renumbered; assigned UP 6318-6420 in December 1999 (UP 6895 assigned UP 6424).
4. These 273 units are assigned UP numbers not in SP sequence; SP 375-378 assigned UP 6268, 6295, 6302, 6325, the numbers that would have been held by the four previously renumbered units (SP 221, 249, 256, 279) assigned to the UP 6421-6424 series.
5. UP's designation for these units is C44AC; GE's designation is AC4400CW.
6. By July 2016, there was only one former SP AC4400CW still in SP paint. That ended on July 29, 2016 when SP 343 was repainted as UP 6308. Scott Thomas wrote on Trainorders.com, "It was the last locomotive working on the UP with SP reporting marks. Currently it is still in the Jenks Shop at North Little Rock, AR, but it should be back out on the road within a few weeks wearing a new coat of Armour Yellow. There are around 100 ex-SP locomotives still on the UP roster that have avoided UP paint thus far with only a patch renumbering. The numbers of the "patches" have been dropping fast lately, with a long overdue repainting push by the UP currently in progress. In the end, it has taken a little short of 20 years for the last SP lettered locomotive to become a UP lettered locomotive."

Notes:

1. UP 6247 was renumbered from UP 6895, which had been renumbered from SP 279 on 4 July 1998.
2. UP 6347 builder date changed from July 1995 to April 1995 based on builder plate checked by Norm Metcalf, as UP 6347.
3. SP 343 was the last former SP unit with SP reporting marks. It was repainted as UP 6308 on July 29, 2016.
4. UP 6416 (ex SP 370) was the first unit in this group to be renumbered, completed on 24 May 2000.

General Notes:

1. Of the original total of 277 former SP C44ACs, only these four units were renumbered to their previously assigned UP number series, UP 6380-6549 (for SP 100-271) and 6888-6994 (for SP 272-378); the other 273 units were renumbered direct to the UP 6148-6420 group.
2. UP's designation for these units is C44AC; GE's designation is AC4400CW.
3. Assigned as part of the UP 6380-6549 series and the 6888-6994 series in September 1997, four units (UP 6500, 6527, 6534, 6895) renumbered; assigned UP 6421-6424 in December 1999.

Notes:

1. UP 6422, as SP 249, was wrecked on 12 September 1998 at Shawnee Junction, Wyoming; moved to Coast Engine & Equipment Co., Tacoma, Washington, for wreck damage repairs in February 1999; repairs completed, as UP 6527, and returned to service on 14 September 1999. While being repainted, an incorrect builder's number was applied to the unit; it now has builder's number 48810 instead of the correct 48610.
2. UP 6423 (ex UP 6534, ex SP 256) was the first in this group to be repainted to Union Pacific, completed on 18 June 1997.

General Notes:

1. UP's designation for these units is C44AC; GE's designation is AC4400CW.
2. SP 100-271 assigned UP 6380-6549 in September 1997, three units (6500, 6527, 6534) renumbered; assigned UP 6148-6317 in December 1999; the above three renumbered units were assigned UP 6421-6423 in December 1999 to clear the 6500 series for use by new C44ACs in January to June 2000.

Notes:

1. UP 6527, as SP 249, was wrecked on 12 September 1998 at Shawnee Junction, Wyoming; moved to Coast Engine & Equipment Co., Tacoma, Washington, for wreck damage repairs in February 1999; repairs completed and returned to service on 14 September 1999 as UP 6527. While being repainted, an incorrect builder's number was applied to the unit; it now has builder's number 48810 instead of the correct 48610.
2. UP 6534 (ex SP 256) was the first in this group to be repainted to Union Pacific, completed on 18 June 1997.

General Notes:

1. These units were delivered in builder's number sequence, but in reverse road number sequence, beginning with the highest-numbered unit, UP 6549, to allow UP time to renumber the two former SP C44ACs that occupied the same number series, UP 6527 (ex SP 249), renumbered to UP 6422 on 28 February 2000, and UP 6534 (ex SP 256), renumbered to UP 6423 on 29 February 2000.

Notes:

1. UP 6546 apparently has two frame batch numbers, 1920-04 and 1911-169. (checked by Norm Metcalf)