SP DS-4-4-1000 page: 1965 system renumbering
1965 Renumbering:
In late 1965, the SP began a program to renumber the majority of its locomotive fleet into a consolodated system without regard for reporting mark. However, the SSW units did retain their identity, but the numbers were assigned within the overall scheme.
SSW 1851-1854:
| 1965 numbers | Orig. numbers | notes |
| SP 1851 | SSW 1023 | assigned, but never applied |
| SP 1852 | SSW 1024 | assigned, but never applied |
| SP 1853 | SSW 1026 | assigned, but never applied |
| SP 1854 | SSW 1027 | assigned, but never applied |
SP 1863-1869:
| 1965 numbers | Orig. numbers | notes |
| SP 1863 | SP 1393 | |
| SP 1864 | SP 1396 | |
| SP 1865 | SP 1397 | |
| SP 1866 | SP 1399 | assigned, but never applied |
| SP 1867 | SP 1400 | |
| SP 1868 | SP 1401 | |
| SP 1869 | SP 1402 |